2. Human Immunodeficiency Virus Two types:-HIV-1 and HIV-2 HIV-1 is most common worldwide HIV-2 is most common in west Africa It is a Retrovirus Family:- Retroviridae Sub-family:-Lentivirinae It has Reverse Transcriptase Enzyme It is RNA dependant DNA Polymerase Normally DNA RNA Proteins But in HIV RNADNA mRNA Proteins Here Reverse Transcriptase converts RNA into DNA
14. These points of life cycle are important for therapeutic purpose:- RTase inhibitors:-NRTI:- Zidovudine, Lamivudine, Stavudine ect. NNRTI:- Nevirapine, Efavirenz Protease inhibitors:-Ritonavir, Indinavir ect Integrase inhibitors Fusion inhibitors:-inhibits fusion of HIV with CD4 cells:-Enfuvirtide
15. Modes of Transmission Sexual:-Homosexual, Heterosexual Blood, blood products and other body fluids Mother to foetus Breast Milk
16. No risk with Casual contact Eating Insects:-Mosquitoes Sharing things
17. Sexual Transmission Most common and important More risk in Homosexual Virus concentrates in seminal fluid, vaginal and cervical secretions Receptive anal intercourse has more risk because:- Thin fragile rectal mucus membrane Trauma during intercourse
18. Vaginal intercourse Is also important although vaginal mucosa is several layer thick than anal mucosa and less chances of trauma Chances of infection from male to female are more than female to male because:- Semen remains for longer time in vagina as compare to penis in vaginal secretions STDs:-Increases the risk due to:- Infection increases the vascularity of mucosa->increases langerhan’s cells Infection->Genital ulcer->increases risk
19. Lack of circumcision:- increases risk due to:- Increased susceptibility to STDs Increased susceptibility to micro trauma Highly vascular foreskin has more lymphocyte and langerhan cells Moist environment beneath foreskin ->increase micro flora inflammation increase T cells Increases risk Oral sex less eficient than anal or vaginal but not totally safe
20. Blood, blood product and body fluids Transfusion related from:- Whole blood Platelets FFP Packed red cell Clotting factors
21. Previously was very imp. Mode of transmission Now there is screening of blood for HIV,HBV,HCV in all authorized blood banks all over the world Despite best efforts risk can not be completely eliminated since current technology can not detect HIV RNA for first 1-2 wks of inf. Due to very low level of viremia Infection of hemophiliacs has been reduced due to heat treatment of clotting factors HIV can be killed at 30*C for 30 min Hyper immune gamma globulin, HBV Ig, HBV vaccine and Rh immunoglobulin have no risk due to processing which kills HIV
22. Intravenous Drug Users They have high risk of infection due to:- Sharing injections, needles and syringes Water used to mix the drug Cotton through which drug is filtered I/V puncture is not necessary. S/C or I/m injection can transmit the disease
23. Risk increases with Duration of drug used Frequency of needle sharing Number of partners I/v > S/c or I/m
24. Occupational Exposure Small but definite and potential risk Person at risk are:- Health care worker (HCWs) Surgeons Lab Technicians All other who works with HIV infected material
25. Needle Stick Injury Most common mode Risk of HIV:- 0.3% HBV:- 6-30% HCV:- 1.8% 1ml of infected blood has 50 HIV RNA compared with 109 HBV particles There are incidences when patient was positive for HBV and HIV both but the HCW became infected with HBV only Hollow needles 10 times more dangerous than solid needles
26. Most of needle injuries(27%) occurs from improper disposal Injury occurs most commonly on Index finger and Palm adjacent to thumb of non dominant hand
27. Factors associated with increased risk of transmission Deep injury Presence of visible blood on instrument Device placed directly in vein or artery Early or terminal illness in patient High viral load Source patient dies within 2 months of exposure Large diameter needle
28. Mucus membrane contact Due to spillage or splash of infected material on face, mouth, eyes etc. Risk :- 0.09% Intact skin has no risk
29. Non intact skin If HCW has injury to any body part Abrasion of skin Ulcer of skin Average risk not known Risk is less than mucus membrane contact Risk of infection from body fluids other than blood is less but has not been quantified
30. Various body fluids causing infection High risk Blood Amniotic fluids CSF Breast milk Pericardial fluid Peritonial fluid Pleural fluid Synovial fluid Unfixed tissue or organ Vaginal sec. Seminal fluid Sliva associated with dental procedure Low risk Urine Vomit Saliva Faeces Sweat Tears
31. Mother to fetus or infant Can occur during pregnancy, delivery or breast feeding Imp. In developing countries Perinatal most common because:- HIV IgA increases 3-6 months after birth Culture and P24 antigenimia increases wks to months after birth PCR becomes positive many months after birth Cesarean section decreases transmission
32. In the absence of prophylactic ART probability of transmission is:- 15-25% in developed countries 25-35% in developing countries This is due to:- Adequate prenatal and natal care Better general health of pregnant female
33. Factor associated with high transmission Well documented High maternal viremia Low CD4 count Prolonged interval b/w membrane rupture and delivery Potential Chorioamnionitis STDs Preterm delivery Cigarette smoking Vit A deficiency Obstetric procedure like:- Amniocentesis Fetal scalp electrode episiotomy
34. Breast feeding Imp. In developing countries where it is continued for long time Factor that increase the risk:- Detectable HIV In breast milk Mastitis Low CD4 count Vit. A deficiency
35. Risk highest in early months of breast feed avoidance of breast feeding is controversial Although vit. A deficiency increase the risk but its supplementation does’t protects
36. Clinical Manifestations Spectrum changes from:- Primary infection (with or without acute syndrome) clinical latency symptomatic disease Means HIV +ve patient may not be having AIDS, but an AIDS patient will always be HIV +ve. Acute symptoms:- 50-70% experience acute syndrome 3-6 wks after primary infection It remains for 1 to several wks Due to high viremia n low CD4 count
38. Seroconversion period Also called window period Extend from day of HIV exposure to the day of appearance of HIV antibodies in blood This is 12 wks(3 months) During this HIV test will be negetive
39. Clinical latency Average period is 7-10 yrs During this pt is infected Virus replicates CD4 count progressively decreasing No symptoms Av. Rate of T cell decline is 50/µl/yr
40. Symptomatic disease AIDS:-anyone with CD4 count <200/µl or having opportunistic diseases (infections/ neoplasm) Infection are:- bacterial:-TB MAC inf MDR TB Salmonellosis Viral:- VZV HSV CMV
41. Protozoan :- PCP Toxoplasmosis Fungal Cryptococus Histoplasmosis Coccidioides immitis Neoplasm Kaposi sarcoma Lymphoma Peri anal warts Melanoma Testis n oral cancer
42. Prophylaxis Better than cure V. imp. Because no cure of HIV/AIDS Mortality 100% Safe sex:-be faithful to your partner Use condoms or other barrier methods during intercourse Avoid unnatural ways of sex like anal sex Early recognition of STDs n treatment
43. Universal precautions Concept by US CDC Every specimen should be handled as if it came from someone infected with blood borne disease All patients treated with full infection controlled procedures Not possible to apply to all so UK NHS has given concept of “Standard precautions”
44. Standard precautions Within any category of operations there are general precautions appropriate for the procedure with additional specific precautions for different patients So all pts should be screened n additional precautions applied to those who r HIV POSITIVE or high risk:- Homosexual IDUs Haemophiliac Partner of a member of one of the above group
45. Presentation to surgeon HIV positive pt may present with any disease that are normally managed by the surgeon with specific conditions related to HIV syndrome like:- Colorectal n anal ds Lymph node excision biopsy Splenectomy for thrombocytopenia Chronic venous assess These ds are treated in the same way as in HIV negative pts
46. Training n education Corner stone of all infection control programmes Should be provided to all staff at all levels Main focus on:- Modes of transmission Use of std precautions Disposal of sharps n body fluids Issue of stigma n discrimination Human rights n obligations Area posting of warning signs
47. Screening of patients Screening of all patients for HIV, HBV, HCV is very important Even if HIV test is negative, it is not 100% sure that patient is not infected because Patient may be in window period when HIV antibodies have not yet formed in the patient (detected by the HIV test kits) So precautionary measures are very important
48. Methods of prevention Barrier method Methodical approach to all procedures Proper care n disposal of sharps Controlled n deliberate manner of procedure
49. Barrier method Can prevent >50% exposure Gloves:- need to wear gloves while doing any of the following procedure:- Dressing a wound Starting I/V drip Taking blood samples Doing any operative procedure Doing PR, PV or oral cavity exam
50. No need to wear Physical exam of pt when the pt has no open wound Giving I/M inj
51. Double gloves Two pairs of gloves produces better protection Single glove can reduce the volume of blood from needle injury by 50% Double gloves give extra protection Risk can be reduced by 5 folds Bt it decreases the sensitivity of hand n fingers More comfortable to wear large glove inside n a ½ size smaller glove outside
52. Use only good quality gloves Use only disposable gloves Gloves should be discarded after single use Should not be washed or disinfected as:- Micro-organisms can not be easily washed Washing may enhance the penetration of liquid through unidentified holes Disinfection can deteriorate the gloves
53. If glove breaks during procedure immediately change it After use dispose of in plastic bags Cap n mask Need to be worn during any operation No need to wear in ward In ward wear only while doing major dressings
54. Eye glasses or shields Certain situations where need to be worn:- Orthopedic OT:-high speed drills or bone cutters used Obstetric OT:-during delivery Dental procedure:-high speed drills used General surgery OT:-require exposure to medium sized arteries which may get injured
55. Plastic apron/gown During prolonged procedure, excessive blood loss or body fluid spillage surgeon’s gown may get soaked at the level of operating table Surgeon’s under clothes may get soaked So plastic apron should be worn
56. Footwear To wear “chappals” in OT is very unsafe Wear the footwear that will protect the feet, ankle and lower part of legs Wellington shoes are of this type n should be used Contaminated shoes should be removed while wearing gloves Should be brush scrubbed with soap n hot water Use disposable shoe coverings
57. Methodical approach Carry out operation in orderly manner Surgical assistants should be minimum Reduce the number of staff in OT to cover essential roles only Remove all extra equipments Staff members having abrasions eczema should be excluded Avoid any in coordination in passing instruments
58. Clearly announce while handing over sharp instrument Use kidney tray to pass instruments Use retractors only to retract the tissue Assistants should be still when surgeon is doing any delicate procedure like suturing or sharp dissection When assistant is changing the position surgeon should stop operating All procedure should be done in correct sequence
59. Controlled and deliberate manner Maintain attention to hemostasis Avoid unexpected bleeding Don’t be panicky Don’t be in hurry Stitching should be done with needle holder n forceps Retraction to the tissue with free hand must be with utmost care
60. While stitching the only movement should be by the surgeon, assistant should stay still Where possible use alternative methods like blunt suture needles, staples, surgical adhesives, cautery Thimbles to protect the index finger of non dominant hand Magnetic pads to place sharps Scalpel blade should be removed from blade holder with clamp or artery forceps
61. Disposal of sharps n body fluids After use sharps should be placed in puncture proof containers puncture proof containers must be available near the operating area Should not be thrown on the floor or in garbage container
62. All the body fluids should be handled with utmost care taking all the precautions Swabs should be counted, but not left exposed on the instrument troley, should be placed in deep swab pockets
63. Disposable instruments should be placed in yellow bags, sealed n double bagged with a hazard label attached Soiled linen should be handled as little as possible with minimum agitation Placed into special bags, marked and send to laundry Normal laundry cycles should be used Bulk blood, suctioned fluid, excretions and secretions should be placed in leakage proof container n carefully poured down a drain
64. Infective material should either be incinerated or decontaminated before disposal in a sanitary fill All spills on floor should be cleaned with 1:1000 solution of house hold bleach Soiled cleaning equipments should be cleaned and decontaminated or disposed off properly
65. Hand washing V. imp. Practice to prevent infection Hands must be washed before wearing gloves Use of gloves doesn’t eliminates the need for washing Hands should be washed when gloves are removed Wash immediately after unprotected exposure After a glove tears or breaks Before leaving a work area
66. In emergency care Risk is more in emergency department due to:- HIV status of the patient who comes in emergency is not known Patient needs urgent care so can not wait for HIV test report HCWs have to work quickly sometimes no time to think about precautionary measures
67. Precautions Disposable gloves should be the standard component of emergency equipment Gloves should be donned by all personnel prior to initiate any emergency patient care Extra pair of gloves should be available Gloves should fit tightly at the wrist Gloves should be changed b/w patient contacts
68. While wearing gloves avoid handling personal items like pen, comb etc. Gloves should be removed taking care to avoid contact with exterior surface Mask, eye shields and gowns should be available in emergency These should be used according to the level of exposure Needles should not be recapped If recapping can not be avoided either use One handed “scoop” technique or Mechanical device to hold the needle sheath
69. Needles should not be bent or broken by hand Should not be removed from syringe Should be burnt in needle incinerator Or placed with syringe in puncture proof container Reusable needles should be left on syringes in a puncture proof container No transmission during mouth to mouth respiration has been documented
70. But because of risk salivary transmission of other inf. And theoretical risk of HIV n HBV during artificial ventilation, disposable airway equipments and resuscitation bags should be used Disposable should be used once n then disposed off If reusable thoroughly cleaned n disinfected after each use Hands should be washed after every procedure, removing gloves or if contaminated
71. To prevent infection to patients Patient safety is 10 concern when giving injectable medication Special attention must be paid to the initial and subsequent use of multi dose vials Changing needles b/w patients but not syringes is not safe practice Same needles may be used for same patient under special circumstances (acupuncture)
72. All reusable syringes n needles must be appropriately cleaned and sterilized by boiling Prior to any blood transfusion full identification of the patient and product must be made HCWs who have previous significant exposure or have potential risk factors must seek HIV,HBV n HCV testing
73. What to do if exposure occurs Gently wash the area with soap n water immediately Blood should be squeezed out of puncture wound Mucus membrane should be irrigated with water, saline or sterile irrigants Eyes should be irrigated with water or saline Full history should be taken about time, type, circumstances of exposure Type of instrument causing injury Gauze of needle, depth of wound
74. Whether gloves were worn or not Whether source pt is known HIV positive or not CD4 count of source HIV RNA load Current or previous ART Any resistance to any drug If status of source is unknown:- Ask to agree to HIV test Enquire about high risk factors
79. Regimens Basic regimen:-Two NRTI for 1 month Zidovudine – 300 mg BD + Lamivudine – 150 mg BD Lamivudine + Stavudine 40 mg BD Didanosine 200mg BD + Stavudine 40mg BD Expended regimen:-Two NRTI+ One PI Zidovudine + Lamivudine + Indinavir 800mg TDS/Ritonavir 100mg BD/Lopinavir 400mg BD/squinavir for 1 month PEP should be started ideally with in 1 hr Preferably with in 72 hr May be considered up to 5 days with specialist advice
80. Side effects PEP is very toxic so its use is weighed against toxicity Should not be used for exposure that poses negligible risk Don’t use three drug regimen for all HIV exposure Most common is nausea and diarrhea Mild n reversible may be relieved by domperidone and loperamide PIs cause peripheral neuropathy Indinavir:- Nephrolithiasis, Hyperbilirubinemia NRTI Abacavir causes hypersensitivity reaction NNRTI not used causes acute fulminant liver failure Efavirenz is teratogenic, Steven Johnson Syndrome, dizziness, insomnia, psychiatric illness
81. Investigations before prescribing PEP Full medical history Risk of pregnancy CBC LFT RFT Zidovudine + Lamivudine + Ritonavir are safe in pregnancy Alone Zidovudine gives 80% protection. Combinations provide extra protection
82. Follow up Perform baseline HIV test of HCW at the time of exposure which will be negative then repeat at 6 wk, 12wk and 6 month interval to see any seroconversion Follow up every 1-2 wk to check side effects, toxicity and adherence to regimen Instruct to seek medical advice immediately if experiences acute viral symptoms Advise to:- have safe sex Use barrier methods during intercourse Don’t donate blood or organs during follow up period
83. Safe to continue performing exposure prone procedure as risk of seroconversion is low and the risk of onward transmission is remote PEP for HBV:->90% effective If source HBV +ve n HCW not previously vaccinated give full vaccine series n HBIg with in 24 hr not later than 1 wk If HCW previously vaccinated check antibody titer if inadequate give 1 dose vaccine n 1 dose HBIg If source HBV negative no need of PEP
84. PEP for HCV No PEP available Follow up up to 6 months Test for antibodies at 3 and 6 month interval LFT every month to detect early acute hepatitis Treatment of acute hepatitis with Interferon +/- Ribavirin can prevent development of chronic hepatitis
85. Conclusion Occupational exposure of HIV,HBV n HCV is small but potential risk Screening of every patient is necessary Personal protective measure with universal precautions with additional safety measures against high risk patients are the mainstay to decrease risk PEP is very imp. N should be started as early as possible without waiting for HIV test report of source patient