Guidelines for Infection Control in Dental Health-Care ...
Morbidity and Mortality Weekly ReportRecommendations and Reports December 19, 2003 / Vol. 52 / No. RR-17 Guidelines for Infection Control in Dental Health-Care Settings — 2003 INSIDE: Continuing Education Examination department of health and human services department services Centers for Disease Control and Prevention
MMWR CONTENTSThe MMWR series of publications is published by the Introduction ......................................................................... 1Epidemiology Program Office, Centers for Disease Background ......................................................................... 2Control and Prevention (CDC), U.S. Department of Previous Recommendations .............................................. 3Health and Human Services, Atlanta, GA 30333. Selected Definitions .......................................................... 4 Review of Science Related to Dental Infection Control ......... 6 SUGGESTED CITATION Personnel Health Elements of an Infection-Control Centers for Disease Control and Prevention. Guidelines Program .......................................................................... 6 for Infection Control in Dental Health-Care Settings Preventing Transmission — 2003. MMWR 2003;52(No. RR-17):[inclusive page of Bloodborne Pathogens ................................................ 10 numbers]. Hand Hygiene ................................................................ 14 Personal Protective Equipment ........................................ 16 Contact Dermatitis and Latex Hypersensitivity ................. 19 Centers for Disease Control and Prevention Sterilization and Disinfection of Patient-Care Items ......... 20 Julie L. Gerberding, M.D., M.P.H. Environmental Infection Control ..................................... 25 Director Dental Unit Waterlines, Biofilm, and Water Quality ......... 28 Special Considerations ...................................................... 30 Dixie E. Snider, Jr., M.D., M.P.H. Dental Handpieces and Other Devices Attached (Acting) Deputy Director for Public Health Science to Air and Waterlines .................................................... 30 Susan Y. Chu, Ph.D., M.S.P.H. Saliva Ejectors ................................................................ 31 (Acting) Associate Director for Science Dental Radiology ............................................................ 31 Aseptic Technique for Parenteral Medications ................. 31 Epidemiology Program Office Single-Use or Disposable Devices ................................... 32 Stephen B. Thacker, M.D., M.Sc. Preprocedural Mouth Rinses ........................................... 32 Director Oral Surgical Procedures ................................................ 32 Handling of Biopsy Specimens ........................................ 33Office of Scientific and Health Communications Handling of Extracted Teeth ............................................ 33 John W. Ward, M.D. Dental Laboratory ........................................................... 33 Director Laser/Electrosurgery Plumes or Surgical Smoke .............. 34 Editor, MMWR Series M. tuberculosis ................................................................. 35 Creutzfeldt-Jakob Disease and Other Prion Diseases ...... 36 Suzanne M. Hewitt, M.P.A. Program Evaluation ........................................................ 37 Managing Editor, MMWR Series Infection-Control Research Considerations ..................... 38 C. Kay Smith-Akin, M.Ed. Recommendations ............................................................. 39 Lead Technical Writer/Editor Infection-Control Internet Resources ................................. 48 Acknowledgement ............................................................. 48 C. Kay Smith-Akin, M.Ed. References ......................................................................... 48 Douglas W. Weatherwax Appendix A ....................................................................... 62 Project Editors Appendix B ........................................................................ 65 Appendix C ....................................................................... 66 Beverly J. Holland Continuing Education Activity* ....................................... CE-1 Lead Visual Information Specialist Malbea A. LaPete Visual Information Specialist * For Continuing Dental Education (CDE), see http://www.ada.org. Kim L. Bright, M.B.A. To request additional copies of this report, contact CDCs Division Quang M. Doan, M.B.A. of Oral Health by e-mail: firstname.lastname@example.org; telephone: 770-488- Erica R. Shaver 6054; or fax: 770-488-6080. Information Technology Specialists Disclosure of Relationship Our subject matter experts wish to disclose they have no financial interests or other relationships with the manufacture of commercial products, providers of commercial services, or commercial supporters. This report does not include any discussion of the unlabeled use of commercial products or products for investigational use.
Vol. 52 / RR-17 Recommendations and Reports 1 Guidelines for Infection Control in Dental Health-Care Settings — 2003 Prepared by William G. Kohn, D.D.S.1 Amy S. Collins, M.P.H.1 Jennifer L. Cleveland, D.D.S.1 Jennifer A. Harte, D.D.S.2 Kathy J. Eklund, M.H.P.3 Dolores M. Malvitz, Dr.P.H.1 1 Division of Oral Health National Center for Chronic Disease Prevention and Health Promotion, CDC 2 United States Air Force Dental Investigation Service Great Lakes, Illinois 3 The Forsyth Institute Boston, Massachusetts Summary This report consolidates previous recommendations and adds new ones for infection control in dental settings. Recommendations are provided regarding 1) educating and protecting dental health-care personnel; 2) preventing transmission of bloodborne patho- gens; 3) hand hygiene; 4) personal protective equipment; 5) contact dermatitis and latex hypersensitivity; 6) sterilization and disinfection of patient-care items; 7) environmental infection control; 8) dental unit waterlines, biofilm, and water quality; and 9) special considerations (e.g., dental handpieces and other devices, radiology, parenteral medications, oral surgical procedures, and dental laboratories). These recommendations were developed in collaboration with and after review by authorities on infection control from CDC and other public agencies, academia, and private and professional organizations. Introduction • hand-hygiene products and surgical hand antisepsis; • contact dermatitis and latex hypersensitivity; This report consolidates recommendations for preventing • sterilization of unwrapped instruments;and controlling infectious diseases and managing personnel • dental water-quality concerns (e.g., dental unit waterlinehealth and safety concerns related to infection control in den- biofilms; delivery of water of acceptable biological qualitytal settings. This report 1) updates and revises previous CDC for patient care; usefulness of flushing waterlines; use ofrecommendations regarding infection control in dental set- sterile irrigating solutions for oral surgical procedures;tings (1,2); 2) incorporates relevant infection-control measures handling of community boil-water advisories);from other CDC guidelines; and 3) discusses concerns not • dental radiology;addressed in previous recommendations for dentistry. These • aseptic technique for parenteral medications;updates and additional topics include the following: • preprocedural mouth rinsing for patients; • application of standard precautions rather than universal • oral surgical procedures; precautions; • laser/electrosurgery plumes; • work restrictions for health-care personnel (HCP) infected • tuberculosis (TB); with or occupationally exposed to infectious diseases; • Creutzfeldt-Jakob disease (CJD) and other prion-related • management of occupational exposures to bloodborne diseases; pathogens, including postexposure prophylaxis (PEP) for • infection-control program evaluation; and work exposures to hepatitis B virus (HBV), hepatitis C • research considerations. virus (HCV); and human immunodeficiency virus (HIV); These guidelines were developed by CDC staff members in • selection and use of devices with features designed to pre- collaboration with other authorities on infection control. Draft vent sharps injury; documents were reviewed by other federal agencies and profes- sional organizations from the fields of dental health care, public The material in this report originated in the National Center for Chronic health, and hospital epidemiology and infection control. A Fed- Disease Prevention and Health Promotion, James S. Marks, M.D., eral Register notice elicited public comments that were consid- M.P.H., Director; and the Division of Oral Health, William R. Maas, D.D.S., M.P.H., Director. ered in the decision-making process. Existing guidelines and published research pertinent to dental infection-control prin-
2 MMWR December 19, 2003ciples and practices were reviewed. Wherever possible, recom- droplets (e.g., spatter) containing microorganisms generatedmendations are based on data from well-designed scientific stud- from an infected person and propelled a short distance (e.g.,ies. However, only a limited number of studies have characterized by coughing, sneezing, or talking); and 4) inhalation of air-risk factors and the effectiveness of prevention measures for borne microorganisms that can remain suspended in the airinfections associated with dental health-care practices. for long periods (5). Some infection-control practices routinely used by health- Infection through any of these routes requires that all of thecare practitioners cannot be rigorously examined for ethical or following conditions be present:logistical reasons. In the absence of scientific evidence for such • a pathogenic organism of sufficient virulence and inpractices, certain recommendations are based on strong theo- adequate numbers to cause disease;retical rationale, suggestive evidence, or opinions of respected • a reservoir or source that allows the pathogen to surviveauthorities based on clinical experience, descriptive studies, or and multiply (e.g., blood);committee reports. In addition, some recommendations are • a mode of transmission from the source to the host;derived from federal regulations. No recommendations are • a portal of entry through which the pathogen can enteroffered for practices for which insufficient scientific evidence the host; andor lack of consensus supporting their effectiveness exists. • a susceptible host (i.e., one who is not immune). Occurrence of these events provides the chain of infection (6). Effective infection-control strategies prevent disease transmis- Background sion by interrupting one or more links in the chain. In the United States, an estimated 9 million persons work in Previous CDC recommendations regarding infection con-health-care professions, including approximately 168,000 den- trol for dentistry focused primarily on the risk of transmissiontists, 112,000 registered dental hygienists, 218,000 dental of bloodborne pathogens among DHCP and patients and useassistants (3), and 53,000 dental laboratory technicians (4). of universal precautions to reduce that risk (1,2,7,8). Univer-In this report, dental health-care personnel (DHCP) refers to sal precautions were based on the concept that all blood andall paid and unpaid personnel in the dental health-care setting body fluids that might be contaminated with blood should bewho might be occupationally exposed to infectious materials, treated as infectious because patients with bloodborne infec-including body substances and contaminated supplies, equip- tions can be asymptomatic or unaware they are infected (9,10).ment, environmental surfaces, water, or air. DHCP include Preventive practices used to reduce blood exposures, particu-dentists, dental hygienists, dental assistants, dental laboratory larly percutaneous exposures, include 1) careful handling oftechnicians (in-office and commercial), students and trainees, sharp instruments, 2) use of rubber dams to minimize bloodcontractual personnel, and other persons not directly involved spattering; 3) handwashing; and 4) use of protective barriersin patient care but potentially exposed to infectious agents (e.g., (e.g., gloves, masks, protective eyewear, and gowns).administrative, clerical, housekeeping, maintenance, or vol- The relevance of universal precautions to other aspects ofunteer personnel). Recommendations in this report are disease transmission was recognized, and in 1996, CDCdesigned to prevent or reduce potential for disease transmis- expanded the concept and changed the term to standard pre-sion from patient to DHCP, from DHCP to patient, and from cautions. Standard precautions integrate and expand the ele-patient to patient. Although these guidelines focus mainly on ments of universal precautions into a standard of care designedoutpatient, ambulatory dental health-care settings, the recom- to protect HCP and patients from pathogens that can be spreadmended infection-control practices are applicable to all set- by blood or any other body fluid, excretion, or secretion (11).tings in which dental treatment is provided. Standard precautions apply to contact with 1) blood; 2) all Dental patients and DHCP can be exposed to pathogenic body fluids, secretions, and excretions (except sweat), regard-microorganisms including cytomegalovirus (CMV), HBV, less of whether they contain blood; 3) nonintact skin; and 4)HCV, herpes simplex virus types 1 and 2, HIV, Mycobacte- mucous membranes. Saliva has always been considered arium tuberculosis, staphylococci, streptococci, and other viruses potentially infectious material in dental infection control; thus,and bacteria that colonize or infect the oral cavity and respira- no operational difference exists in clinical dental practicetory tract. These organisms can be transmitted in dental set- between universal precautions and standard precautions.tings through 1) direct contact with blood, oral fluids, or other In addition to standard precautions, other measures (e.g.,patient materials; 2) indirect contact with contaminated expanded or transmission-based precautions) might be neces-objects (e.g., instruments, equipment, or environmental sur- sary to prevent potential spread of certain diseases (e.g., TB,faces); 3) contact of conjunctival, nasal, or oral mucosa with influenza, and varicella) that are transmitted through airborne,
Vol. 52 / RR-17 Recommendations and Reports 3droplet, or contact transmission (e.g., sneezing, coughing, and commitment and accountability of all DHCP. This report iscontact with skin) (11). When acutely ill with these diseases, designed to provide guidance to DHCP for preventing diseasepatients do not usually seek routine dental outpatient care. transmission in dental health-care settings, for promoting a safeNonetheless, a general understanding of precautions for dis- working environment, and for assisting dental practices ineases transmitted by all routes is critical because 1) some DHCP developing and implementing infection-control programs. Theseare hospital-based or work part-time in hospital settings; programs should be followed in addition to practices and pro-2) patients infected with these diseases might seek urgent treat- cedures for worker protection required by the Occupationalment at outpatient dental offices; and 3) DHCP might Safety and Health Administration’s (OSHA) standards forbecome infected with these diseases. Necessary transmission- occupational exposure to bloodborne pathogens (13),based precautions might include patient placement (e.g., iso- including instituting controls to protect employees fromlation), adequate room ventilation, respiratory protection (e.g., exposure to blood or other potentially infectious materialsN-95 masks) for DHCP, or postponement of nonemergency (OPIM), and requiring implementation of a written exposure-dental procedures. control plan, annual employee training, HBV vaccinations, and DHCP should be familiar also with the hierarchy of con- postexposure follow-up (13). Interpretations and enforcementtrols that categorizes and prioritizes prevention strategies (12). procedures are available to help DHCP apply this OSHA stan-For bloodborne pathogens, engineering controls that elimi- dard in practice (14). Also, manufacturer’s Material Safety Datanate or isolate the hazard (e.g., puncture-resistant sharps con- Sheets (MSDS) should be consulted regarding correct proce-tainers or needle-retraction devices) are the primary strategies dures for handling or working with hazardous chemicals (15).for protecting DHCP and patients. Where engineering con-trols are not available or appropriate, work-practice controls Previous Recommendationsthat result in safer behaviors (e.g., one-hand needle recapping This report includes relevant infection-control measures fromor not using fingers for cheek retraction while using sharp the following previously published CDC guidelines and rec-instruments or suturing), and use of personal protective equip- ommendations:ment (PPE) (e.g., protective eyewear, gloves, and mask) can • CDC. Guideline for disinfection and sterilization inprevent exposure (13). In addition, administrative controls health-care facilities: recommendations of CDC and the(e.g., policies, procedures, and enforcement measures targeted Healthcare Infection Control Practices Advisory Commit-at reducing the risk of exposure to infectious persons) are a tee (HICPAC). MMWR (in press).priority for certain pathogens (e.g., M. tuberculosis), particu- • CDC. Guidelines for environmental infection control inlarly those spread by airborne or droplet routes. health-care facilities: recommendations of CDC and the Dental practices should develop a written infection-control Healthcare Infection Control Practices Advisory Commit-program to prevent or reduce the risk of disease transmission. tee (HICPAC). MMWR 2003;52(No. RR-10).Such a program should include establishment and implemen- • CDC. Guidelines for the prevention of intravasculartation of policies, procedures, and practices (in conjunction catheter-related infections. MMWR 2002;51(No. RR-10).with selection and use of technologies and products) to pre- • CDC. Guideline for hand hygiene in health-care settings:vent work-related injuries and illnesses among DHCP as well recommendations of the Healthcare Infection Controlas health-care–associated infections among patients. The pro- Practices Advisory Committee and the HICPAC/SHEA/gram should embody principles of infection control and APIC/IDSA Hand Hygiene Task Force. MMWR 2002;51occupational health, reflect current science, and adhere to rel- (No. RR-16).evant federal, state, and local regulations and statutes. An • CDC. Updated U.S. Public Health Service guidelines forinfection-control coordinator (e.g., dentist or other DHCP) the management of occupational exposures to HBV, HCV,knowledgeable or willing to be trained should be assigned and HIV and recommendations for postexposure prophy-responsibility for coordinating the program. The effectiveness laxis. MMWR 2001;50(No. RR-11).of the infection-control program should be evaluated on a day- • Mangram AJ, Horan TC, Pearson ML, Silver LC, Jarvisto-day basis and over time to help ensure that policies, proce- WR, Hospital Infection Control Practices Advisory Com-dures, and practices are useful, efficient, and successful (see mittee. Guideline for prevention of surgical site infection,Program Evaluation). 1999. Infect Control Hosp Epidemiol 1999;20:250–78. Although the infection-control coordinator remains respon- • Bolyard EA, Tablan OC, Williams WW, Pearson ML,sible for overall management of the program, creating and main- Shapiro CN, Deitchman SD, Hospital Infection Controltaining a safe work environment ultimately requires the Practices Advisory Committee. Guideline for infection
4 MMWR December 19, 2003 control in health care personnel, 1998. Am J Infect Con- Bioburden: Microbiological load (i.e., number of viable trol 1998;26:289–354. organisms in or on an object or surface) or organic material on • CDC. Immunization of health-care workers: recommen- a surface or object before decontamination, or sterilization. dations of the Advisory Committee on Immunization Prac- Also known as bioload or microbial load. tices (ACIP) and the Hospital Infection Control Practices Colony-forming unit (CFU): The minimum number (i.e., Advisory Committee (HICPAC). MMWR 1997;46(No. tens of millions) of separable cells on the surface of or in semi- RR-18). solid agar medium that give rise to a visible colony of progeny. • Rutala WA, Association for Professionals in Infection CFUs can consist of pairs, chains, clusters, or as single cells Control and Epidemiology, Inc. APIC guideline for selec- and are often expressed as colony-forming units per milliliter tion and use of disinfectants. Am J Infect Control (CFUs/mL). 1996;24:313–42. Decontamination: Use of physical or chemical means to • Garner JS, Hospital Infection Control Practices Advisory remove, inactivate, or destroy pathogens on a surface or item Committee. Guideline for isolation precautions in hospi- so that they are no longer capable of transmitting infectious tals. Infect Control Hosp Epidemiol 1996;17:53–80. particles and the surface or item is rendered safe for handling, • Larson EL, 1992, 1993, and 1994 Guidelines Committee. use, or disposal. APIC guideline for handwashing and hand antisepsis in Dental treatment water: Nonsterile water used during dental health-care settings. Am J Infect Control 1995;23:251–69. treatment, including irrigation of nonsurgical operative sites • CDC. Guidelines for preventing the transmission of and cooling of high-speed rotary and ultrasonic instruments. Mycobacterium tuberculosis in health-care facilities, 1994. Disinfectant: A chemical agent used on inanimate objects MMWR 1994;43(No. RR-13). (e.g., floors, walls, or sinks) to destroy virtually all recognized • CDC. Recommendations for preventing transmission of pathogenic microorganisms, but not necessarily all microbial human immunodeficiency virus and hepatitis B virus to forms (e.g., bacterial endospores). The U.S. Environmental patients during exposure-prone invasive procedures. Protection Agency (EPA) groups disinfectants on the basis of MMWR 1991;40(No. RR-8). whether the product label claims limited, general, or hospital • Garner JS. CDC guideline for prevention of surgical disinfectant capabilities. wound infections, 1985. Supersedes guideline for preven- Disinfection: Destruction of pathogenic and other kinds of tion of surgical wound infections published in 1982. microorganisms by physical or chemical means. Disinfection (Originally published in November 1985). Revised. is less lethal than sterilization, because it destroys the majority Infect Control 1986;7:193–200. of recognized pathogenic microorganisms, but not necessarily • Garner JS, Favero MS. CDC guideline for handwashing all microbial forms (e.g., bacterial spores). Disinfection does and hospital environmental control, 1985. Infect Control not ensure the degree of safety associated with sterilization 1986;7:231–43. processes. Droplet nuclei: Particles <5 µm in diameter formed by dehy-Selected Definitions dration of airborne droplets containing microorganisms that can remain suspended in the air for long periods of time. Alcohol-based hand rub: An alcohol-containing preparation Droplets: Small particles of moisture (e.g., spatter) generateddesigned for reducing the number of viable microorganisms when a person coughs or sneezes, or when water is convertedon the hands. to a fine mist by an aerator or shower head. These particles, Antimicrobial soap: A detergent containing an antiseptic agent. intermediate in size between drops and droplet nuclei, can Antiseptic: A germicide used on skin or living tissue for the contain infectious microorganisms and tend to quickly settlepurpose of inhibiting or destroying microorganisms (e.g., from the air such that risk of disease transmission is usuallyalcohols, chlorhexidine, chlorine, hexachlorophene, iodine, limited to persons in close proximity to the droplet source.chloroxylenol [PCMX], quaternary ammonium compounds, Endotoxin: The lipopolysaccharide of gram-negative bacte-and triclosan). ria, the toxic character of which resides in the lipid protein. Bead sterilizer: A device using glass beads 1.2–1.5 mm Endotoxins can produce pyrogenic reactions in personsdiameter and temperatures 217ºC–232ºC for brief exposures exposed to their bacterial component.(e.g., 45 seconds) to inactivate microorganisms. (This term is Germicide: An agent that destroys microorganisms, especiallyactually a misnomer because it has not been cleared by the pathogenic organisms. Terms with the same suffix (e.g., viru-Food and Drug Administration [FDA] as a sterilizer). cide, fungicide, bactericide, tuberculocide, and sporicide) indi-
Vol. 52 / RR-17 Recommendations and Reports 5cate agents that destroy the specific microorganism identified Implantable device: Device placed into a surgically or natu-by the prefix. Germicides can be used to inactivate microor- rally formed cavity of the human body and intended toganisms in or on living tissue (i.e., antiseptics) or on environ- remain there for >30 days.mental surfaces (i.e., disinfectants). Independent water reservoir: Container used to hold water or Hand hygiene: General term that applies to handwashing, other solutions and supply it to handpieces and air and waterantiseptic handwash, antiseptic hand rub, or surgical hand syringes attached to a dental unit. The independent reservoir,antisepsis. which isolates the unit from the public water system, can be Health-care–associated infection: Any infection associated with provided as original equipment or as a retrofitted device.a medical or surgical intervention. The term health-care– Intermediate-level disinfection: Disinfection process thatassociated replaces nosocomial, which is limited to adverse inactivates vegetative bacteria, the majority of fungi, myco-infectious outcomes occurring in hospitals. bacteria, and the majority of viruses (particularly enveloped Hepatitis B immune globulin (HBIG): Product used for pro- viruses) but not bacterial spores.phylaxis against HBV infection. HBIG is prepared from plasma Intermediate-level disinfectant: Liquid chemical germicidecontaining high titers of hepatitis B surface antibody (anti- registered with EPA as a hospital disinfectant and with a labelHBs) and provides protection for 3–6 mos. claim of potency as tuberculocidal (Appendix A). Hepatitis B surface antigen (HBsAg): Serologic marker on the Latex: Milky white fluid extracted from the rubber treesurface of HBV detected in high levels during acute or chronic Hevea brasiliensis that contains the rubber material cis-1,4hepatitis. The body normally produces antibodies to surface polyisoprene.antigen as a normal immune response to infection. Low-level disinfection: Process that inactivates the majority Hepatitis B e antigen (HBeAg): Secreted product of the nucleo- of vegetative bacteria, certain fungi, and certain viruses, butcapsid gene of HBV found in serum during acute and chronic cannot be relied on to inactivate resistant microorganisms (e.g.,HBV infection. Its presence indicates that the virus is replicat- mycobacteria or bacterial spores).ing and serves as a marker of increased infectivity. Low-level disinfectant: Liquid chemical germicide registered Hepatitis B surface antibody (anti-HBs): Protective antibody with EPA as a hospital disinfectant. OSHA requires low-levelagainst HBsAg. Presence in the blood can indicate past infec- hospital disinfectants also to have a label claim for potencytion with, and immunity to, HBV, or immune response from against HIV and HBV if used for disinfecting clinical contacthepatitis B vaccine. surfaces (Appendix A). Heterotrophic bacteria: Those bacteria requiring an organic Microfilter: Membrane filter used to trap microorganismscarbon source for growth (i.e., deriving energy and carbon from suspended in water. Filters are usually installed on dental unitorganic compounds). waterlines as a retrofit device. Microfiltration commonly High-level disinfection: Disinfection process that inactivates occurs at a filter pore size of 0.03–10 µm. Sediment filtersvegetative bacteria, mycobacteria, fungi, and viruses but not commonly found in dental unit water regulators have porenecessarily high numbers of bacterial spores. FDA further sizes of 20–90 µm and do not function as microbiologicaldefines a high-level disinfectant as a sterilant used for a shorter filters.contact time. Nosocomial: Infection acquired in a hospital as a result of Hospital disinfectant: Germicide registered by EPA for use medical care.on inanimate objects in hospitals, clinics, dental offices, and Occupational exposure: Reasonably anticipated skin, eye,other medical-related facilities. Efficacy is demonstrated against mucous membrane, or parenteral contact with blood or OPIMSalmonella choleraesuis, Staphylococcus aureus, and Pseudomo- that can result from the performance of an employee’s duties.nas aeruginosa. OPIM: Other potentially infectious materials. OPIM is an Iatrogenic: Induced inadvertently by HCP, medical (includ- OSHA term that refers to 1) body fluids including semen,ing dental) treatment, or diagnostic procedures. Used particu- vaginal secretions, cerebrospinal fluid, synovial fluid, pleurallarly in reference to an infectious disease or other complication fluid, pericardial fluid, peritoneal fluid, amniotic fluid, salivaof treatment. in dental procedures; any body fluid visibly contaminated with Immunization: Process by which a person becomes immune, blood; and all body fluids in situations where differentiatingor protected against a disease. Vaccination is defined as the between body fluids is difficult or impossible; 2) any unfixedprocess of administering a killed or weakened infectious tissue or organ (other than intact skin) from a human (livingorganism or a toxoid; however, vaccination does not always or dead); and 3) HIV-containing cell or tissue cultures, organresult in immunity.
6 MMWR December 19, 2003cultures; HIV- or HBV-containing culture medium or other Review of Science Relatedsolutions; and blood, organs, or other tissues from experimen- to Dental Infection Controltal animals infected with HIV or HBV. Parenteral: Means of piercing mucous membranes or skin Personnel Health Elementsbarrier through such events as needlesticks, human bites, cuts, of an Infection-Control Programand abrasions. Persistent activity: Prolonged or extended activity that pre- A protective health component for DHCP is an integral partvents or inhibits proliferation or survival of microorganisms of a dental practice infection-control program. The objectivesafter application of a product. This activity can be demon- are to educate DHCP regarding the principles of infectionstrated by sampling a site minutes or hours after application control, identify work-related infection risks, institute preven-and demonstrating bacterial antimicrobial effectiveness when tive measures, and ensure prompt exposure management andcompared with a baseline level. Previously, this property was medical follow-up. Coordination between the dental practice’ssometimes termed residual activity. infection-control coordinator and other qualified health-care Prion: Protein particle lacking nucleic acid that has been professionals is necessary to provide DHCP with appropriateimplicated as the cause of certain neurodegenerative diseases services. Dental programs in institutional settings, (e.g., hos-(e.g., scrapie, CJD, and bovine spongiform encephalopathy pitals, health centers, and educational institutions) can coor-[BSE]). dinate with departments that provide personnel health services. Retraction: Entry of oral fluids and microorganisms into However, the majority of dental practices are in ambulatory,waterlines through negative water pressure. private settings that do not have licensed medical staff and Seroconversion: The change of a serological test from nega- facilities to provide complete on-site health service programs.tive to positive indicating the development of antibodies in In such settings, the infection-control coordinator shouldresponse to infection or immunization. establish programs that arrange for site-specific infection- Sterile: Free from all living microorganisms; usually described control services from external health-care facilities and pro-as a probability (e.g., the probability of a surviving microor- viders before DHCP are placed at risk for exposure. Referralganism being 1 in 1 million). arrangements can be made with qualified health-care profes- Sterilization: Use of a physical or chemical procedure to sionals in an occupational health program of a hospital, withdestroy all microorganisms including substantial numbers of educational institutions, or with health-care facilities thatresistant bacterial spores. offer personnel health services. Surfactants: Surface-active agents that reduce surface tension Education and Trainingand help cleaning by loosening, emulsifying, and holding soil Personnel are more likely to comply with an infection-in suspension, to be more readily rinsed away. control program and exposure-control plan if they understand Ultrasonic cleaner: Device that removes debris by a process its rationale (5,13,16). Clearly written policies, procedures,called cavitation, in which waves of acoustic energy are propa- and guidelines can help ensure consistency, efficiency, andgated in aqueous solutions to disrupt the bonds that hold par- effective coordination of activities. Personnel subject to occu-ticulate matter to surfaces. pational exposure should receive infection-control training on Vaccination: See immunization. initial assignment, when new tasks or procedures affect their Vaccine: Product that induces immunity, therefore protect- occupational exposure, and at a minimum, annually (13).ing the body from the disease. Vaccines are administered Education and training should be appropriate to the assignedthrough needle injections, by mouth, and by aerosol. duties of specific DHCP (e.g., techniques to prevent cross- Washer-disinfector: Automatic unit that cleans and thermally contamination or instrument sterilization). For DHCP whodisinfects instruments, by using a high-temperature cycle rather perform tasks or procedures likely to result in occupationalthan a chemical bath. exposure to infectious agents, training should include 1) a Wicking: Absorption of a liquid by capillary action along a description of their exposure risks; 2) review of prevention strat-thread or through the material (e.g., penetration of liquids egies and infection-control policies and procedures; 3) discus-through undetected holes in a glove). sion regarding how to manage work-related illness and injuries, including PEP; and 4) review of work restrictions for the exposure or infection. Inclusion of DHCP with minimal exposure risks (e.g., administrative employees) in education and training programs might enhance facilitywide understand-
Vol. 52 / RR-17 Recommendations and Reports 7ing of infection-control principles and the importance of the of work-related illness and work restrictions (if appropriate)program. Educational materials should be appropriate in con- for exposed or infected DHCP.tent and vocabulary for each person’s educational level, lit- Exposure Prevention and Postexposureeracy, and language, as well as be consistent with existing federal, Managementstate, and local regulations (5,13). Avoiding exposure to blood and OPIM, as well as protec-Immunization Programs tion by immunization, remain primary strategies for reducing DHCP are at risk for exposure to, and possible infection occupationally acquired infections, but occupational exposureswith, infectious organisms. Immunizations substantially can still occur (19). A combination of standard precautions,reduce both the number of DHCP susceptible to these dis- engineering, work practice, and administrative controls is theeases and the potential for disease transmission to other DHCP best means to minimize occupational exposures. Written poli-and patients (5,17). Thus, immunizations are an essential part cies and procedures to facilitate prompt reporting, evaluation,of prevention and infection-control programs for DHCP, and counseling, treatment, and medical follow-up of all occupa-a comprehensive immunization policy should be implemented tional exposures should be available to all DHCP. Writtenfor all dental health-care facilities (17,18). The Advisory Com- policies and procedures should be consistent with federal, state,mittee on Immunization Practices (ACIP) provides national and local requirements addressing education and training,guidelines for immunization of HCP, which includes DHCP postexposure management, and exposure reporting (see Pre-(17). Dental practice immunization policies should incorpo- venting Transmission of Bloodborne Pathogens).rate current state and federal regulations as well as recommen- DHCP who have contact with patients can also be exposeddations from the U.S. Public Health Service and professional to persons with infectious TB, and should have a baseline tu-organizations (17) (Appendix B). berculin skin test (TST), preferably by using a two-step test, On the basis of documented health-care–associated trans- at the beginning of employment (20). Thus, if an unprotectedmission, HCP are considered to be at substantial risk for occupational exposure occurs, TST conversions can be distin-acquiring or transmitting hepatitis B, influenza, measles, guished from positive TST results caused by previous expo-mumps, rubella, and varicella. All of these diseases are vac- sures (20,21). The facility’s level of TB risk will determine thecine-preventable. ACIP recommends that all HCP be vacci- need for routine follow-up TSTs (see Special Considerations).nated or have documented immunity to these diseases (5,17). Medical Conditions, Work-Related Illness,ACIP does not recommend routine immunization of HCP and Work Restrictionsagainst TB (i.e., inoculation with bacille Calmette-Guérin vac-cine) or hepatitis A (17). No vaccine exists for HCV. ACIP DHCP are responsible for monitoring their own health sta-guidelines also provide recommendations regarding immuni- tus. DHCP who have acute or chronic medical conditionszation of HCP with special conditions (e.g., pregnancy, HIV that render them susceptible to opportunistic infection shouldinfection, or diabetes) (5,17). discuss with their personal physicians or other qualified Immunization of DHCP before they are placed at risk for authority whether the condition might affect their ability toexposure remains the most efficient and effective use of vac- safely perform their duties. However, under certain circum-cines in health-care settings. Some educational institutions and stances, health-care facility managers might need to excludeinfection-control programs provide immunization schedules DHCP from work or patient contact to prevent further trans-for students and DHCP. OSHA requires that employers make mission of infection (22). Decisions concerning work restric-hepatitis B vaccination available to all employees who have tions are based on the mode of transmission and the period ofpotential contact with blood or OPIM. Employers are also infectivity of the disease (5) (Table 1). Exclusion policies shouldrequired to follow CDC recommendations for vaccinations, 1) be written, 2) include a statement of authority that definesevaluation, and follow-up procedures (13). Nonpatient-care who can exclude DHCP (e.g., personal physicians), and 3) bestaff (e.g., administrative or housekeeping) might be included, clearly communicated through education and training. Poli-depending on their potential risk of coming into contact with cies should also encourage DHCP to report illnesses or expo-blood or OPIM. Employers are also required to ensure that sures without jeopardizing wages, benefits, or job status.employees who decline to accept hepatitis B vaccination sign With increasing concerns regarding bloodborne pathogens andan appropriate declination statement (13). DHCP unable or introduction of universal precautions, use of latex gloves amongunwilling to be vaccinated as required or recommended should HCP has increased markedly (7,23). Increased use of these glovesbe educated regarding their exposure risks, infection-control has been accompanied by increased reports of allergic reactionspolicies and procedures for the facility, and the management to natural rubber latex among HCP, DHCP, and patients
8 MMWR December 19, 2003TABLE 1. Suggested work restrictions for health-care personnel infected with or exposed to major infectious diseases in health-care settings, in the absence of state and local regulations*Disease/problem Work restriction DurationConjunctivitis Restrict from patient contact and contact with patient’s Until discharge ceases environment.Cytomegalovirus infection No restrictionDiarrheal disease Acute stage (diarrhea with other symptoms) Restrict from patient contact, contact with patient’s Until symptoms resolve environment, and food-handling. Convalescent stage, Salmonella species Restrict from care of patients at high risk. Until symptoms resolve; consult with local and state health authorities regarding need for negative stool culturesEnteroviral infection Restrict from care of infants, neonates, and Until symptoms resolve immunocompromised patients and their environments.Hepatitis A Restrict from patient contact, contact with patient’s Until 7 days after onset of jaundice environment, and food-handing.Hepatitis B Personnel with acute or chronic hepatitis B No restriction†; refer to state regulations. Standard surface antigenemia who do not perform precautions should always be followed. exposure-prone procedures Personnel with acute or chronic hepatitis B Do not perform exposure-prone invasive procedures until Until hepatitis B e antigen is negative e antigenemia who perform exposure-prone counsel from a review panel has been sought; panel procedures should review and recommend procedures that personnel can perform, taking into account specific procedures as well as skill and technique. Standard precautions should always be observed. Refer to state and local regulations or recommendations.Hepatitis C No restrictions on professional activity.† HCV-positive health-care personnel should follow aseptic technique and standard precautions.Herpes simplex Genital No restriction Hands (herpetic whitlow) Restrict from patient contact and contact with patient’s Until lesions heal environment. Orofacial Evaluate need to restrict from care of patients at high risk.Human immunodeficiency virus; personnel who Do not perform exposure-prone invasive procedures untilperform exposure-prone procedures counsel from an expert review panel has been sought; panel should review and recommend procedures that personnel can perform, taking into account specific procedures as well as skill and technique. Standard precautions should always be observed. Refer to state and local regulations or recommendations.Measles Active Exclude from duty Until 7 days after the rash appears Postexposure (susceptible personnel) Exclude from duty From fifth day after first exposure through twenty-first day after last exposure, or 4 days after rash appearsMeningococcal infection Exclude from duty Until 24 hours after start of effective therapyMumps Active Exclude from duty Until 9 days after onset of parotitis Postexposure (susceptible personnel) Exclude from duty From twelfth day after first exposure through twenty-sixth day after last exposure, or until 9 days after onset of parotitisSource: Adapted from Bolyard EA, Hospital Infection Control Practices Advisory Committee. Guidelines for infection control in health care personnel, 1998. Am J Infect Control1998;26:289–354.* Modified from recommendations of the Advisory Committee on Immunization Practices (ACIP).† Unless epidemiologically linked to transmission of infection.§ Those susceptible to varicella and who are at increased risk of complications of varicella (e.g., neonates and immunocompromised persons of any age).¶ Patients at high risk as defined by ACIP for complications of influenza.
Vol. 52 / RR-17 Recommendations and Reports 9TABLE 1. (Continued) Suggested work restrictions for health-care personnel infected with or exposed to major infectious diseasesin health-care settings, in the absence of state and local regulations*Disease/problem Work restriction DurationPediculosis Restrict from patient contact Until treated and observed to be free of adult and immature licePertussis Active Exclude from duty From beginning of catarrhal stage through third week after onset of paroxysms, or until 5 days after start of effective antibiotic therapy Postexposure (asymptomatic personnel) No restriction, prophylaxis recommended Postexposure (symptomatic personnel) Exclude from duty Until 5 days after start of effective antibiotic therapyRubella Active Exclude from duty Until 5 days after rash appears Postexposure (susceptible personnel) Exclude from duty From seventh day after first exposure through twenty-first day after last exposureStaphylococcus aureus infection Active, draining skin lesions Restrict from contact with patients and patient’s Until lesions have resolved environment or food handling. Carrier state No restriction unless personnel are epidemiologically linked to transmission of the organismStreptococcal infection, group A Restrict from patient care, contact with patient’s Until 24 hours after adequate treatment started environment, and food-handling.Tuberculosis Active disease Exclude from duty Until proved noninfectious PPD converter No restrictionVaricella (chicken pox) Active Exclude from duty Until all lesions dry and crust Postexposure (susceptible personnel) Exclude from duty From tenth day after first exposure through twenty-first day (twenty-eighth day if varicella-zoster immune globulin [VZIG] administered) after last exposure.Zoster (shingles) Localized, in healthy person Cover lesions, restrict from care of patients§ at high risk Until all lesions dry and crust Generalized or localized in immunosup- Restrict from patient contact Until all lesions dry and crust pressed person Postexposure (susceptible personnel) Restrict from patient contact From tenth day after first exposure through twenty-first day (twenty-eighth day if VZIG administered) after last exposure; or, if varicella occurs, when lesions crust and dryViral respiratory infection, acute febrile Consider excluding from the care of patients at high risk¶ Until acute symptoms resolve or contact with such patients’ environments during community outbreak of respiratory syncytial virus and influenzaSource: Adapted from Bolyard EA, Hospital Infection Control Practices Advisory Committee. Guidelines for infection control in health care personnel, 1998. Am J Infect Control1998;26:289–354.* Modified from recommendations of the Advisory Committee on Immunization Practices (ACIP).† Unless epidemiologically linked to transmission of infection.§ Those susceptible to varicella and who are at increased risk of complications of varicella (e.g., neonates and immunocompromised persons of any age).¶ Patients at high risk as defined by ACIP for complications of influenza.
10 MMWR December 19, 2003(24–30), as well as increased reports of irritant and allergic con- infected blood can result in transmission from patient totact dermatitis from frequent and repeated use of hand-hygiene DHCP, from DHCP to patient, and from one patient toproducts, exposure to chemicals, and glove use. another. The opportunity for transmission is greatest from DHCP should be familiar with the signs and symptoms of patient to DHCP, who frequently encounter patient blood andlatex sensitivity (5,31–33). A physician should evaluate DHCP blood-contaminated saliva during dental procedures.exhibiting symptoms of latex allergy, because further exposure Since 1992, no HIV transmission from DHCP to patientscould result in a serious allergic reaction. A diagnosis is made has been reported, and the last HBV transmission from DHCPthrough medical history, physical examination, and diagnos- to patients was reported in 1987. HCV transmission fromtic tests. Procedures should be in place for minimizing latex- DHCP to patients has not been reported. The majority ofrelated health problems among DHCP and patients while DHCP infected with a bloodborne virus do not pose a risk toprotecting them from infectious materials. These procedures patients because they do not perform activities meeting theshould include 1) reducing exposures to latex-containing necessary conditions for transmission. For DHCP to pose amaterials by using appropriate work practices, 2) training and risk for bloodborne virus transmission to patients, DHCP musteducating DHCP, 3) monitoring symptoms, and 4) substitut- 1) be viremic (i.e., have infectious virus circulating in the blood-ing nonlatex products where appropriate (32) (see Contact stream); 2) be injured or have a condition (e.g., weeping der-Dermatitis and Latex Hypersensitivity). matitis) that allows direct exposure to their blood or other infectious body fluids; and 3) enable their blood or infectiousMaintenance of Records, Data Management, body fluid to gain direct access to a patient’s wound, trauma-and Confidentiality tized tissue, mucous membranes, or similar portal of entry. The health status of DHCP can be monitored by maintain- Although an infected DHCP might be viremic, unless the sec-ing records of work-related medical evaluations, screening tests, ond and third conditions are also met, transmission cannotimmunizations, exposures, and postexposure management. occur.Such records must be kept in accordance with all applicable The risk of occupational exposure to bloodborne viruses isstate and federal laws. Examples of laws that might apply largely determined by their prevalence in the patient popula-include the Privacy Rule of the Health Insurance Portability tion and the nature and frequency of contact with blood andand Accountability Act (HIPAA) of 1996, 45 CFR 160 and body fluids through percutaneous or permucosal routes of164, and the OSHA Occupational Exposure to Bloodborne exposure. The risk of infection after exposure to a bloodbornePathogens; Final Rule 29 CFR 1910.1030(h)(1)(i–iv) (34,13). virus is influenced by inoculum size, route of exposure, andThe HIPAA Privacy Rule applies to covered entities, includ- susceptibility of the exposed HCP (12). The majority ofing certain defined health providers, health-care clearinghouses, attention has been placed on the bloodborne pathogens HBV,and health plans. OSHA requires employers to ensure that HCV, and HIV, and these pathogens present different levelscertain information contained in employee medical records is of risk to DHCP.1) kept confidential; 2) not disclosed or reported without theemployee’s express written consent to any person within or Hepatitis B Virusoutside the workplace except as required by the OSHA stan- HBV is a well-recognized occupational risk for HCP (36,37).dard; and 3) maintained by the employer for at least the dura- HBV is transmitted by percutaneous or mucosal exposure totion of employment plus 30 years. Dental practices that blood or body fluids of a person with either acute or chroniccoordinate their infection-control program with off-site pro- HBV infection. Persons infected with HBV can transmit theviders might consult OSHA’s Bloodborne Pathogen standard virus for as long as they are HBsAg-positive. The risk of HBVand employee Access to Medical and Exposure Records stan- transmission is highly related to the HBeAg status of the sourcedard, as well as other applicable local, state, and federal laws, person. In studies of HCP who sustained injuries from needlesto determine a location for storing health records (13,35). contaminated with blood containing HBV, the risk of devel- oping clinical hepatitis if the blood was positive for both HBsAgPreventing Transmission and HBeAg was 22%–31%; the risk of developing serologicof Bloodborne Pathogens evidence of HBV infection was 37%–62% (19). By compari- son, the risk of developing clinical hepatitis from a needle con- Although transmission of bloodborne pathogens (e.g., HBV, taminated with HBsAg-positive, HBeAg-negative blood wasHCV, and HIV) in dental health-care settings can have seri- 1%–6%, and the risk of developing serologic evidence of HBVous consequences, such transmission is rare. Exposure to infection, 23%–37% (38).
Vol. 52 / RR-17 Recommendations and Reports 11 Blood contains the greatest proportion of HBV infectious from dentist to patient has not been reported since 1987, pos-particle titers of all body fluids and is the most critical vehicle sibly reflecting such factors as 1) adoption of universal precau-of transmission in the health-care setting. HBsAg is also found tions, 2) routine glove use, 3) increased levels of immunity asin multiple other body fluids, including breast milk, bile, cere- a result of hepatitis B vaccination of DHCP, 4) implementa-brospinal fluid, feces, nasopharyngeal washings, saliva, semen, tion of the 1991 OSHA bloodborne pathogen standard (68),sweat, and synovial fluid. However, the majority of body flu- and 5) incomplete ascertainment and reporting. Only one caseids are not efficient vehicles for transmission because they con- of patient-to-patient transmission of HBV in the dental set-tain low quantities of infectious HBV, despite the presence of ting has been documented (CDC, unpublished data, 2003).HBsAg (19). The concentration of HBsAg in body fluids can In this case, appropriate office infection-control proceduresbe 100–1,000-fold greater than the concentration of infec- were being followed, and the exact mechanism of transmis-tious HBV particles (39). sion was undetermined. Although percutaneous injuries are among the most effi- Because of the high risk of HBV infection among HCP,cient modes of HBV transmission, these exposures probably DHCP who perform tasks that might involve contact withaccount for only a minority of HBV infections among HCP. blood, blood-contaminated body substances, other body flu-In multiple investigations of nosocomial hepatitis B outbreaks, ids, or sharps should be vaccinated (2,13,17,19,69). Vaccina-the majority of infected HCP could not recall an overt percu- tion can protect both DHCP and patients from HBV infectiontaneous injury (40,41), although in certain studies, approxi- and, whenever possible, should be completed when dentistsmately one third of infected HCP recalled caring for a patient or other DHCP are in training and before they have contactwho was HBsAg-positive (42,43). In addition, HBV has been with blood.demonstrated to survive in dried blood at room temperature Prevaccination serological testing for previous infection ison environmental surfaces for <1 week (44). Thus, HBV not indicated, although it can be cost-effective where preva-infections that occur in HCP with no history of nonoccupa- lence of infection is expected to be high in a group of potentialtional exposure or occupational percutaneous injury might have vacinees (e.g., persons who have emigrated from areas withresulted from direct or indirect blood or body fluid exposures high rates of HBV infection). DHCP should be tested for anti-that inoculated HBV into cutaneous scratches, abrasions, HBs 1–2 months after completion of the 3-dose vaccinationburns, other lesions, or on mucosal surfaces (45–47). The series (17). DHCP who do not develop an adequate antibodypotential for HBV transmission through contact with envi- response (i.e., anti-HBs <10 mIU/mL) to the primary vaccineronmental surfaces has been demonstrated in investigations of series should complete a second 3-dose vaccine series or beHBV outbreaks among patients and HCP in hemodialysis units evaluated to determine if they are HBsAg-positive (17).(48–50). Revaccinated persons should be retested for anti-HBs at the Since the early 1980s, occupational infections among HCP completion of the second vaccine series. Approximately halfhave declined because of vaccine use and adherence to univer- of nonresponders to the primary series will respond to a sec-sal precautions (51). Among U.S. dentists, >90% have been ond 3-dose series. If no antibody response occurs after thevaccinated, and serologic evidence of past HBV infection second series, testing for HBsAg should be performed (17).decreased from prevaccine levels of 14% in 1972 to approxi- Persons who prove to be HBsAg-positive should be counseledmately 9% in 1992 (52). During 1993–2001, levels remained regarding how to prevent HBV transmission to others andrelatively unchanged (Chakwan Siew, Ph.D., American Den- regarding the need for medical evaluation. Nonresponders total Association, Chicago, Illinois, personal communication, vaccination who are HBsAg-negative should be consideredJune 2003). Infection rates can be expected to decline further susceptible to HBV infection and should be counseled regard-as vaccination rates remain high among young dentists and as ing precautions to prevent HBV infection and the need toolder dentists with lower vaccination rates and higher rates of obtain HBIG prophylaxis for any known or probable parenteralinfection retire. exposure to HBsAg-positive blood. Although the potential for transmission of bloodborne Vaccine-induced antibodies decline gradually over time, andinfections from DHCP to patients is considered limited 60% of persons who initially respond to vaccination will lose(53–55), precise risks have not been quantified by carefully detectable antibodies over 12 years. Even so, immunity con-designed epidemiologic studies (53,56,57). Reports published tinues to prevent clinical disease or detectable viral infectionduring 1970–1987 describe nine clusters in which patients (17). Booster doses of vaccine and periodic serologic testing towere thought to be infected with HBV through treatment by monitor antibody concentrations after completion of the vac-an infected DHCP (58–67). However, transmission of HBV cine series are not necessary for vaccine responders (17).
12 MMWR December 19, 2003Hepatitis D Virus HCP, including 33 dentists or dental students (55,93). No An estimated 4% of persons with acute HBV infection are additional cases of transmission were documented.also infected with hepatitis Delta virus (HDV). Discovered in Prospective studies worldwide indicate the average risk of1977, HDV is a defective bloodborne virus requiring the pres- HIV infection after a single percutaneous exposure toence of HBV to replicate. Patients coinfected with HBV and HIV-infected blood is 0.3% (range: 0.2%–0.5%) (94). AfterHDV have substantially higher mortality rates than those an exposure of mucous membranes in the eye, nose, or mouth,infected with HBV alone. Because HDV infection is depen- the risk is approximately 0.1% (76). The precise risk of trans-dent on HBV for replication, immunization to prevent HBV mission after skin exposure remains unknown but is believedinfection, through either pre- or postexposure prophylaxis, can to be even smaller than that for mucous membrane exposure.also prevent HDV infection (70). Certain factors affect the risk of HIV transmission after an occupational exposure. Laboratory studies have determined ifHepatitis C Virus needles that pass through latex gloves are solid rather than Hepatitis C virus appears not to be transmitted efficiently hollow-bore, or are of small gauge (e.g., anesthetic needlesthrough occupational exposures to blood. Follow-up studies commonly used in dentistry), they transfer less blood (36). Inof HCP exposed to HCV-infected blood through percutane- a retrospective case-control study of HCP, an increased riskous or other sharps injuries have determined a low incidence for HIV infection was associated with exposure to a relativelyof seroconversion (mean: 1.8%; range, 0%–7%) (71–74). One large volume of blood, as indicated by a deep injury with astudy determined transmission occurred from hollow-bore device that was visibly contaminated with the patient’s blood,needles but not other sharps (72). Although these studies have or a procedure that involved a needle placed in a vein or arterynot documented seroconversion associated with mucous mem- (95). The risk was also increased if the exposure was to bloodbrane or nonintact skin exposure, at least two cases of HCV from patients with terminal illnesses, possibly reflecting thetransmission from a blood splash to the conjunctiva (75,76) higher titer of HIV in late-stage AIDS.and one case of simultaneous transmission of HCV and HIV Exposure Prevention Methodsafter nonintact skin exposure have been reported (77). Data are insufficient to estimate the occupational risk of Avoiding occupational exposures to blood is the primaryHCV infection among HCP, but the majority of studies indi- way to prevent transmission of HBV, HCV, and HIV, to HCPcate the prevalence of HCV infection among dentists, sur- in health-care settings (19,96,97). Exposures occur throughgeons, and hospital-based HCP is similar to that among the percutaneous injury (e.g., a needlestick or cut with a sharpgeneral population, approximately 1%–2% (78–86). In a study object), as well as through contact between potentially infec-that evaluated risk factors for infection, a history of uninten- tious blood, tissues, or other body fluids and mucous mem-tional needlesticks was the only occupational risk factor inde- branes of the eye, nose, mouth, or nonintact skin (e.g., exposedpendently associated with HCV infection (80). skin that is chapped, abraded, or shows signs of dermatitis). No studies of transmission from HCV-infected DHCP to Observational studies and surveys indicate that percutane-patients have been reported, and the risk for such transmis- ous injuries among general dentists and oral surgeons occursion appears limited. Multiple reports have been published less frequently than among general and orthopedic surgeonsdescribing transmission from HCV-infected surgeons, which and have decreased in frequency since the mid-1980s (98–102).apparently occurred during performance of invasive procedures; This decline has been attributed to safer work practices, saferthe overall risk for infection averaged 0.17% (87–90). instrumentation or design, and continued DHCP education (103,104). Percutaneous injuries among DHCP usuallyHuman Immunodeficiency Virus 1) occur outside the patient’s mouth, thereby posing less risk In the United States, the risk of HIV transmission in dental for recontact with patient tissues; 2) involve limited amountssettings is extremely low. As of December 2001, a total of 57 of blood; and 3) are caused by burs, syringe needles, labora-cases of HIV seroconversion had been documented among tory knives, and other sharp instruments (99–102,105,106).HCP, but none among DHCP, after occupational exposure to Injuries among oral surgeons might occur more frequentlya known HIV-infected source (91). Transmission of HIV to during fracture reductions using wires (104,107). Experience,six patients of a single dentist with AIDS has been reported, as measured by years in practice, does not appear to affect thebut the mode of transmission could not be determined risk of injury among general dentists or oral surgeons(2,92,93). As of September 30, 1993, CDC had information (100,104,107).regarding test results of >22,000 patients of 63 HIV-infected
Vol. 52 / RR-17 Recommendations and Reports 13 The majority of exposures in dentistry are preventable, and Work-practice controls for needles and other sharps includemethods to reduce the risk of blood contacts have included placing used disposable syringes and needles, scalpel blades,use of standard precautions, use of devices with features engi- and other sharp items in appropriate puncture-resistant con-neered to prevent sharp injuries, and modifications of work tainers located as close as feasible to where the items were usedpractices. These approaches might have contributed to the (2,7,13,113–115). In addition, used needles should never bedecrease in percutaneous injuries among dentists during recapped or otherwise manipulated by using both hands, orrecent years (98–100,103). However, needlesticks and other any other technique that involves directing the point of a needleblood contacts continue to occur, which is a concern because toward any part of the body (2,7,13,97,113,114). A one-percutaneous injuries pose the greatest risk of transmission. handed scoop technique, a mechanical device designed for Standard precautions include use of PPE (e.g., gloves, masks, holding the needle cap to facilitate one-handed recapping, orprotective eyewear or face shield, and gowns) intended to pre- an engineered sharps injury protection device (e.g., needlesvent skin and mucous membrane exposures. Other protective with resheathing mechanisms) should be employed for recap-equipment (e.g., finger guards while suturing) might also ping needles between uses and before disposalreduce injuries during dental procedures (104). (2,7,13,113,114). DHCP should never bend or break needles Engineering controls are the primary method to reduce before disposal because this practice requires unnecessaryexposures to blood and OPIM from sharp instruments and manipulation. Before attempting to remove needles fromneedles. These controls are frequently technology-based and nondisposable aspirating syringes, DHCP should recap themoften incorporate safer designs of instruments and devices (e.g., to prevent injuries. For procedures involving multiple injec-self-sheathing anesthetic needles and dental units designed to tions with a single needle, the practitioner should recap theshield burs in handpieces) to reduce percutaneous injuries needle between injections by using a one-handed technique or(101,103,108). use a device with a needle-resheathing mechanism. Passing a Work-practice controls establish practices to protect DHCP syringe with an unsheathed needle should be avoided becausewhose responsibilities include handling, using, assembling, or of the potential for injury.processing sharp devices (e.g., needles, scalers, laboratory util- Additional information for developing a safety program andity knives, burs, explorers, and endodontic files) or sharps dis- for identifying and evaluating safer dental devices is available atposal containers. Work-practice controls can include removing • http://www.cdc.gov/OralHealth/infectioncontrol/burs before disassembling the handpiece from the dental unit, forms.htm (forms for screening and evaluating safer den-restricting use of fingers in tissue retraction or palpation dur- tal devices), anding suturing and administration of anesthesia, and minimiz- • http://www.cdc.gov/niosh/topics/bbp (state legislation oning potentially uncontrolled movements of such instruments needlestick safety).as scalers or laboratory knives (101,105). Postexposure Management and Prophylaxis As indicated, needles are a substantial source of percutane-ous injury in dental practice, and engineering and work- Postexposure management is an integral component of apractice controls for needle handling are of particular complete program to prevent infection after an occupationalimportance. In 2001, revisions to OSHA’s bloodborne patho- exposure to blood. During dental procedures, saliva is pre-gens standard as mandated by the Needlestick Safety and Pre- dictably contaminated with blood (7,114). Even when bloodvention Act of 2000 became effective. These revisions clarify is not visible, it can still be present in limited quantities andthe need for employers to consider safer needle devices as they therefore is considered a potentially infectious material bybecome available and to involve employees directly respon- OSHA (13,19). A qualified health-care professional shouldsible for patient care (e.g., dentists, hygienists, and dental evaluate any occupational exposure incident to blood or OPIM,assistants) in identifying and choosing such devices (109). Safer including saliva, regardless of whether blood is visible, in den-versions of sharp devices used in hospital settings have become tal settings (13).available (e.g., blunt suture needles, phlebotomy devices, and Dental practices and laboratories should establish written,butterfly needles), and their impact on reducing injuries has comprehensive programs that include hepatitis B vaccinationbeen documented (110–112). Aspirating anesthetic syringes and postexposure management protocols that 1) describe thethat incorporate safety features have been developed for den- types of contact with blood or OPIM that can place DHCP attal procedures, but the low injury rates in dentistry limit risk for infection; 2) describe procedures for promptly report-assessment of their effect on reducing injuries among DHCP. ing and evaluating such exposures; and 3) identify a health-
14 MMWR December 19, 2003care professional who is qualified to provide counseling and the source was infected with HIV, the stage of disease,perform all medical evaluations and procedures in accordance history of antiretroviral therapy, and viral load, if known.with current recommendations of the U.S. Public Health Ser- • Details regarding the exposed person (e.g., hepatitis B vac-vice (PHS), including PEP with chemotherapeutic drugs when cination and vaccine-response status).indicated. DHCP, including students, who might reasonably • Details regarding counseling, postexposure management,be considered at risk for occupational exposure to blood or and follow-up.OPIM should be taught strategies to prevent contact with blood Each occupational exposure should be evaluated individuallyor OPIM and the principles of postexposure management, for its potential to transmit HBV, HCV, and HIV, based onincluding PEP options, as part of their job orientation and the following:training. Educational programs for DHCP and students should • The type and amount of body substance involved.emphasize reporting all exposures to blood or OPIM as soon • The type of exposure (e.g., percutaneous injury, mucousas possible, because certain interventions have to be initiated membrane or nonintact skin exposure, or bites resultingpromptly to be effective. Policies should be consistent with in blood exposure to either person involved).the practices and procedures for worker protection required • The infection status of the source.by OSHA and with current PHS recommendations for man- • The susceptibility of the exposed person (19).aging occupational exposures to blood (13,19). All of these factors should be considered in assessing the risk After an occupational blood exposure, first aid should be for infection and the need for further follow-up (e.g., PEP).administered as necessary. Puncture wounds and other inju- During 1990–1998, PHS published guidelines for PEP andries to the skin should be washed with soap and water; other management of health-care worker exposures to HBV,mucous membranes should be flushed with water. No evidence HCV, or HIV (69,116–119). In 2001, these recommenda-exists that using antiseptics for wound care or expressing fluid tions were updated and consolidated into one set of PHS guide-by squeezing the wound further reduces the risk of bloodborne lines (19). The new guidelines reflect the availability of newpathogen transmission; however, use of antiseptics is not con- antiretroviral agents, new information regarding the use andtraindicated. The application of caustic agents (e.g., bleach) safety of HIV PEP, and considerations regarding employingor the injection of antiseptics or disinfectants into the wound HIV PEP when resistance of the source patient’s virus tois not recommended (19). Exposed DHCP should immedi- antiretroviral agents is known or suspected. In addition, theately report the exposure to the infection-control coordinator 2001 guidelines provide guidance to clinicians and exposedor other designated person, who should initiate referral to the HCP regarding when to consider HIV PEP and recommen-qualified health-care professional and complete necessary dations for PEP regimens (19).reports. Because multiple factors contribute to the risk ofinfection after an occupational exposure to blood, the follow- Hand Hygieneing information should be included in the exposure report, Hand hygiene (e.g., handwashing, hand antisepsis, or surgi-recorded in the exposed person’s confidential medical record, cal hand antisepsis) substantially reduces potential pathogensand provided to the qualified health-care professional: on the hands and is considered the single most critical mea- • Date and time of exposure. sure for reducing the risk of transmitting organisms to • Details of the procedure being performed, including where patients and HCP (120–123). Hospital-based studies have and how the exposure occurred and whether the exposure demonstrated that noncompliance with hand hygiene prac- involved a sharp device, the type and brand of device, and tices is associated with health-care–associated infections and how and when during its handling the exposure occurred. the spread of multiresistant organisms. Noncompliance also • Details of the exposure, including its severity and the type has been a major contributor to outbreaks (123). The preva- and amount of fluid or material. For a percutaneous injury, lence of health-care–associated infections decreases as adher- severity might be measured by the depth of the wound, ence of HCP to recommended hand hygiene measures gauge of the needle, and whether fluid was injected; for a improves (124–126). skin or mucous membrane exposure, the estimated vol- The microbial flora of the skin, first described in 1938, con- ume of material, duration of contact, and the condition sist of transient and resident microorganisms (127). Transient of the skin (e.g., chapped, abraded, or intact) should be flora, which colonize the superficial layers of the skin, are easier noted. to remove by routine handwashing. They are often acquired • Details regarding whether the source material was known by HCP during direct contact with patients or contaminated to contain HIV or other bloodborne pathogens, and, if environmental surfaces; these organisms are most frequently