Hospital acquired infections, also known as nosocomial infections, can be contracted by patients or staff while receiving care in a hospital setting. They are usually caused by failure to follow aseptic techniques during procedures like surgery, IV insertion, or wound care. Patients, staff, and the hospital environment can all be sources of infection. Common routes of transmission include direct contact, droplets, contaminated equipment, and aerosols. Prevention strategies include isolating infectious patients, practicing good hand hygiene, wearing proper PPE, and thoroughly cleaning and disinfecting or sterilizing equipment between uses.

1. Hospital Acquired Infections
( Nosocomial Infections)
Dr Soni Rani
PGT-I
Department of Community Medicine
Katihar Medical College & Hospital

2. Hospital Acquired Infections
(Nosocomial Infections)
• Hospital-acquired infections (HAIs) is defined
as acquiring an infection in the hospital by the
patients or others during their stay and
manifesting either during the hospital stay
itself or after discharge.
Hospital Acquired Infections
(Nosocomial Infections)

3. Definition of Nosocomial Infection
• An infection acquired in hospital by a patient who
was admitted for a reason other than that
infection .
• An infection occurring in a patient in a hospital or
other health care facility in whom the infection
was not present or not incubating at the time of
admission.
• This includes infections acquired in the hospital
but appearing after discharge, and also
occupational infections among staff of the facility.

4. • Infections occurring more than 48 hours after
admission are usually considered nosocomial.
• Infections acquired by Staff/Visitors to
Hospital for OPD services also considered as
Nosocomial infections.
Definition of Nosocomial Infection

5. Prevalence of HAI
• A prevalence survey conducted under the
auspices of WHO showed an average of 8.7%
of hospital patients had nosocomial infections.
• The prevalence of HAI is expected to be about
25 to 40 percent in India.
• At any time, over 1.4 million people
worldwide suffer from infectious
complications acquired in hospital.

6. Incidence of Hospital acquired
infections in India
Source HAI rate( %)
Mehta 2007 (9) 4.4
Taneja 2004 (14) 83.09
Habibi 2008 (15) 52.2
Kamat 2008 (16) 34
Shalini 2010(13) 27.4
Datta 2010* (17) 29.13
Sood 2011*(18) 4.36
Ramana 2012* (19) 41

7. Impact of Nosocomial Infection

8.  compromised patients
 ward and inter-hospital transfers
 antibiotic resistance (MRSA, resistant Gram
negatives)
 increasing workload
 staff pressures
 lack of facilities
 ? lack of concern
HAI is inevitable but some is preventable
(irreducible minimum)
 realistically reducible by 10-30%
H.A.I. IS INCREASING

9. Most Common Sites of Nosocomial
Infections

10. Causes of HAI
• Hospital-acquired infections is usually due to
failure to observe aseptic precautions while
carrying out the hospital procedures such as
surgical operations, IV infusions,
catheterization, dressings of the wounds,
lumber puncture, giving injections, etc.

11. Predisposing Factors
• Development of the resistance by the organisms to the
commonly used drugs
• Overcrowding of the hospitals
• Poor environment of the hospitals, both inside and
outside
• Decreased resistance and increased susceptibility of the
vulnerable groups of patients such as those suffering
from tuberculosis, leprosy, diabetes, severe PEM,
anemia, cardiac patients, old age of the patients, those
who have undergone major surgery, those who are on
steroids, cytotoxic drugs, etc.

12. Cross infection organisms
• METHICILLIN RESISTANT STAPH AUREUS (MRSA)
• Causes about 50% of HAI
• Resistant to Flucoxacillin and usually others
May cause -
Wound infection
Bacteraemia
Skin/soft tissue infection
U.T.I.
Pneumonia etc.
Etiological agents

13. • RESISTANT GRAM NEGATIVE ORGANISMS
• Causes about 45% of HAI
• Resistance to multiple antibiotics
Organisms:
E .coli
Proteus
Enterobacter
Acinetobacter
Pseudomonas aeruginosa
Etiological agents

14. • TUBERCULOSIS
• Open pulmonary TB (Sputum smear positive for AFB)
• VIRAL INFECTIONS
Chicken Pox, (Hepatitis B HIV)
• Both are responsible for about 5% of HAI.
Etiological agents

15. Important means of monitoring HAI
Early detection of trends outbreaks
1. Laboratory Based
Microbiology Laboratory lists +ve organisms
ICN reviews ‘Alert organisms’ reported
2. Ward Based
Ward staff monitor patients
ICN reviews ICN visits wards
HAI Surveillance

16. Diagnostic criteria for Surveillance of
Nosocomial Infections
Type of Nosocomial Infections Simplified Criteria
Surgical site infection
Any purulent discharge, abscess, or
spreading cellulitis at the surgical
site during the month after the
operation.
Urinary infection
Positive urine culture
(1 or 2 species) with at least
105
bacteria/ml, with or without
clinical symptoms.
Respiratory infection
Respiratory symptoms with at
least two of the following signs
appearing during hospitalization:
— cough
— purulent sputum
— new infiltrate on chest
radiograph consistent with
infection

17. Type of Nosocomial
Infections
Simplified Criteria
Vascular Catheter Infection
Inflammation, lymphangitis or purulent
discharge at the insertion site of the
catheter
Septicaemia
Fever or rigours and at least one
positive blood culture
Criteria for Surveillance of Nosocomial
Infections

18. Hospital acquired infection
1. Sources and reservoir of HAI
2. Recipients
3. Route of spread
Hospital Acquired Infections
(Nosocomial Infections)

19. Sources and Reservoirs of HAI
The sources are patients, hospital staff and
the environment.
PATIENTS:
• Patients suffering from infectious diseases
are potential sources of infection.
• These cases may be certain viral infections
(measles, german measles, influenza, viral
hepatitis);

20. • Skin infections (discharging wounds, infected
skin lesions, eczema, psoriasis, boils, bed
sores)
• respiratory infections (sore throat,
pulmonary tuberculosis, chest infection)
• urinary tract infection (E. coli infection).
• All these are very common sources of
hospital acquired infection
Sources and Reservoirs of HAI

21. • STAFF:
• The hospital staff (viz doctors, nurses, ward
boys) who come in close contact with
patients may often be an important source of
cross infection.
• For example, staphylococcus aureus is
commonly carried in the nose or on the skin.
• Haemolytic streptococci may be carried in
the throat and salmonella in the gut.
Sources and Reservoirs of HAI

22. • ENVIRONMENT:
a) Air: Hospital air and dust usually harbors
more bacteriae, which are often pathogenic
an multidrug resistant.
b) Surfaces contaminated by patient’s
secretions, excretions, blood and body-fluids,
animals and insects.
Sources and Reservoirs of HAI

23. c) Inanimate objects:
– Contaminated by the patients: Hospital
equipment, such as thermometer, linen, bed,
table, cot, sanitary installations, etc. medical
equipment such as endoscopes, catheters,
needles, lancets, spatula, vesical probes, etc.
– Contaminated by the hands of any hospital
staff in any part of the hospital (kitchen,
laundry, treatment room, etc.)
Sources and Reservoirs of HAI

24. – Contaminated by visitors
– Contaminated by staff who are ill or are
carriers of microorganisms
– Contaminated by food or contaminated water
– Contaminated by animals and insects.
Sources and Reservoirs of HAI

25. • Thus, man occupies a central position:
a. As reservoir and source of microorganisms
b. As disseminator (communication routes)
c. As recipient or target, thus becoming a new
reservoir.
• All patients in the hospital are potential recipients
of crossinfection.
• Those who are severely ill, chronically ill and on
steroid therapy are all highly susceptible.
Recipients

26. Route of Spread
• The common routes of spread of cross infection are:
a) Direct contact- the organism may be transferred directly
from the hands of a nurse or doctor to a susceptible
patient;
b) Droplet infection- droplets released from nose and throat
through coughing or sneezing:
c) Air-borne particles;
d) Release of hospital dust into the air;
e) Through various hospital procedures, viz, catheterisation,
intravenous procedures, infected cat gut, dressings,
sputum cups, bed pans, urinals etc.

27. Prevention and Control of
Nosocomial Infections

28. Preventions and Control
• Elimination of the Reservoirs or Sources
• Breaking the Channel of Transmission
• Protection of Susceptible Persons
• Administrative Measures

29. Elimination of the Reservoirs or
Sources
1) Care of the staff
2) Care of the Patient
3) Treatment
4) Nursing care

30. Care of the staff
• Hospital staff suffering from any infectious
disease (respiratory or alimentary or any
septic skin lesions) should not attend to their
duties until complete recovery.

31. Care of the Patient
• All acute infectious cases must be admitted in the isolation
ward only. There are three types of wards.
i. Chamber ward (cell ward): This is a separate ward for
separate (individual) patients.
• It is also called isolation ward.
• It has its own ventilation.
• The partition extends from floor to ceiling.
ii. Cubicle ward: In this type, the partition extends from floor
but does not reach ceiling, giving provision for cross-
ventilation.
iii. Open wards: These are general wards wherein many
patients are admitted.

32. Treatment and Nursing care
• Treatment: This should be given correctly and
completely with specific antibiotics.
• Nursing care:
i. Barrier nursing: This means that the hospital staff must
act as barriers to prevent cross-infection by wearing
gowns, gloves, masks, etc. while touching or examining
certain acute infectious cases.
ii. Task nursing: This means posting special nurses for
special duties. For example, a nurse attending to
feeding of a premature child should not attend to the
toilet of the child. Such care is essential in intensive
care unit, premature baby-ward, etc.

33. • Hand washing
• Personal hygiene
• Clothing
• Mask
• Gloves
• Safe injection practices .
Breaking the chain of transmission

34. Why
Don’t Staff Wash
their Hands
(Compliance estimated at less than 50%)

35. Why Not?
• Skin irritation
• Inaccessible hand washing facilities
• Wearing gloves
• Too busy
• Lack of appropriate staff
• Being a physician
(“Improving Compliance with Hand Hygiene in Hospitals” Didier Pittet. Infection
Control and Hospital Epidemiology. Vol. 21 No. 6 Page 381)

36. Why Not?
• Working in high-risk areas
• Lack of hand hygiene promotion
• Lack of role model
• Lack of institutional priority
• Lack of sanction of non-compliers

37. Successful Promotion 
• Education
• Routine observation & feedback
• Engineering controls
–Location of hand basins
–Possible, easy & convenient
–Alcohol-based hand rubs available
• Patient education
(Improving Compliance with Hand Hygiene in Hospitals. Didier Pittet. Infection Control and Hospital
Epidemiology. Vol. 21 No. 6 Page 381)

38. Successful Promotion 
• Reminders in the workplace
• Promote and facilitate skin care
• Avoid understaffing and excessive
workload; Nursing shortages have
caused
Successful Promotion 

39. Hand Hygiene
• Easy, timely access to both hand hygiene and
skin protection is necessary for satisfactory
hand hygiene.
• A study by Pittet showed a 20% increase in
compliance by using feedback and
encouraging the use of alcohol hand rubs

40. Hand Hygiene Techniques
1. Alcohol hand rub
2. Routine hand wash 10-15 seconds
3. Aseptic procedures 1 minute
4. Surgical wash 3-5 minutes

41. Repeat procedures until hands are clean
Routine Hand Wash

42. Alcohol Hand Rubs
• Require less time
• Can be strategically placed
• Readily accessible
• Multiple sites
• All patient care areas

43. Alcohol Hand Rubs
• Acts faster
• Excellent bactericidal activity
• Less irritating (??)
• Sustained improvement

44. Alcohol Hand Rubs
Choose agent carefully:
–Adequate antimicrobial efficacy
–Compatibility with other hand
hygiene products

45. Visible soiling
• Hands that are visibly soiled or
potentially grossly contaminated
with dirt or organic material
MUST by washed with liquid
soap and water

46. Areas Most Frequently Missed
HAHS © 1999

47. Hand Care
• Nails
• Rings
• Hand creams
• Cuts & abrasions
• “Chapping”
• Skin Problems

48. Hand hygiene is the
simplest, most effective
measure for preventing
hospital-acquired
infections.

49. Personal hygiene
• All staff must maintain good personal hygiene.
• Nails must be clean and kept short.
• False nails should not be worn.
• Hair must be worn short or pinned up.
• Beard and moustaches must be kept trimmed
short and clean.

50. Clothing
• Working cloth
• Shoes
• Caps

51. Mask
• Masks of cotton wool, gauze, or paper are
ineffective.
• Paper masks with synthetic material for
filtration are an effective barrier against
microorganisms.
• For patient protection surgical mask is
recommended.
• For staff protection a high efficiency mask is
recommended.

52. Gloves
• Hands must be washed when gloves are removed
or changed.
• Disposable gloves should not be reused.
• Latex or polyvinyl-chloride are the materials
most frequently used for gloves.
• Quality, i.e. absence of porosity or holes and
duration of use vary considerably from one glove
type to another.
• Sensitivity to latex may occur, and the
occupational health programme must have
policies to evaluate and manage this problem.

53. Safe injection practices
• eliminate unnecessary injections
• use sterile needle and syringe
• use disposable needle and syringes, if
possible
• prevent contamination of medications
• follow safe sharps disposal practices

54. Preventing transmission from the
environment
1) Cleaning of the hospital environment
2) Use of hot/superheated water
3) Disinfection of patient equipment
4) Sterilization

55. Cleaning of the hospital environment
• Ninety per cent of microorganisms are present
within “visible dirt”, and the purpose of
routine cleaning is to eliminate this dirt.
• This may be achieved by classifying areas into
one of four hospital zones
— Zone A: no patient contact. Normal domestic
cleaning (e.g. administration, library).

56. • Zone B:
• care of patients who are not infected, and not
highly susceptible, cleaned by a procedure that
does not raise dust.
• Dry sweeping or vacuum cleaners are not
recommended.
• The use of a detergent solution improves the
quality of cleaning.
• Disinfect any areas with visible contamination
with blood or body fluids prior to cleaning.
Cleaning of the hospital environment

57. • Zone C:
• infected patients (isolation wards).
• Clean with a detergent/disinfectant solution,
with separate cleaning equipment for each
room.
Cleaning of the hospital environment

58. — Zone D:
highly-susceptible patients (protective isolation)
or protected areas such as operating suites,
delivery rooms, intensive care units,
premature baby units, casualty departments
and haemodialysis units.
• Clean using a detergent/ disinfectant solution
and separate cleaning equipment.
Cleaning of the hospital environment

59. Disinfection with hot water
Temperature Duration
Sanitary equipment 80 °C 45–60 seconds
Cooking utensils 80 °C 1 minute
Linen 70 °C 25 minute
95 °C 10 Minutes

60. Disinfection of patient equipment
• High-level disinfection (critical) —
• this will destroy all microorganisms, with the
exception of heavy contamination by bacterial
spores.
• Intermediate disinfection (semi-critical) —
this inactivates Mycobacterium tuberculosis
vegetative bacteria, most viruses and most
fungi, but does not necessarily kill bacterial
spores.

61. • Low-level disinfection (non-critical) — this
can kill most bacteria, some viruses and some
fungi, but cannot be relied on for killing more
resistant bacteria such as M. tuberculosis or
bacterial spores.
Disinfection of patient equipment

62. Sterilization
• Sterilization is the destruction of all
microorganisms.
• Operationally this is defined as a decrease in
the microbial load. sterilization can be
achieved by either physical or chemical means
.

63. • Heat (Thermal ) sterilization
• Chemical sterilization
• Radiation sterilization
Sterilization

64. Thermal sterilization
• Wet sterilization( Autoclave) : exposure to steam
saturated with water at 121 °C for 30 minutes, or
134 °C for 13 minutes in an autoclave; (134 °C for
18 minutes for prions).
• Dry sterilization: exposure to 160 °C for 120
minutes, or 170 °C for 60 minutes; Dry
sterilization process is often considered less
reliable than the wet process, particularly for
hollow medical devices.
• Other methods are Flaming, incineration,
tyndallization , glass blade sterilizer

65. Chemical sterilization
• Ethylene oxide and formaldehyde for
sterilization are being phased out in many
countries because of safety and greenhouse
gas emission concerns.
• Peracetic acid is widely used in the United
States and some other countries in automatic
processing systems.

66. Radiation sterilization
• Non-ionizing radiation sterilization- ( UV
Radtiation)
• Ionizing radiation sterilization(Gamma
radiation, X-Ray, Electron Beam Radiation)

67. Protection of Susceptible Persons
1. Highly susceptible persons should be
admitted preferably in the isolation wards.
2. They are protected with vaccinations, e.g.
tetanus, hepatitis B, gas gangrene, etc.
3. Universal blood and body fluid precautions to
be adopted by all the health care workers.

68. Administrative Measures
• There should be a Hospital Infection Control
Committee for surveillance of HAIs, to draw
guidelines for different high risk procedures,
early detection and control of outbreak of HAI
and also to formulate policies (regarding
admission of infectious cases, isolation
facilities, disinfection procedures,etc.) and to
implement them.

69. Infection control committee
• The Hospital-acquired Infection Control
Committee consists of the following
administrative set-up:
• Chairperson: Medical Superintendent
• Member Secretary: Infection Control Officer
(Microbiologist)
• Members: Chiefs of all Clinical Units/Heads of
Deptartment
• Chief of Blood Bank Service

70. • Microbiologist
• Medical Record Officer
• Chief of Nursing Services
• Infection Control Sister
• Invited members: Chiefs of all Supportive
Services (OT, kitchen, laundry, etc.)
Infection control committee

71. • The Committee must meet at least once a
month. Similarly there must be a ‘Control
Board’ at the state level and national level.
Infection control committee

72. Task of ICC
• To review and approve a yearly programme of
activity for surveillance and prevention
• To review epidemiological surveillance data
and identify areas for intervention
• To assess and promote improved practice at
all levels of the health facility
• To ensure appropriate staff training in
infection control and safety

73. • to review risks associated with new technologies,
and monitor infectious risks of new devices and
products, prior to their approval for use
• to review and provide input into investigation of
epidemics
• to communicate and cooperate with other
committees of the hospital with common
interests such as Pharmacy and Therapeutics or
Antimicrobial Use Committee, Biosafety or Health
and Safety Committees, and Blood Transfusion
Committee.
Task of ICC

75. References
• PREVENTION OF HOSPITAL-ACQUIRED INFECTIONS: A
PRACTICAL GUIDE — WHO/CDS/CSR/EPH/2002.12
• Park’s textbook of preventive and social medicine
(23rd Edition)
• Community medicine with recent advances
( A.H.Suryakantha). 3rd Edition.
• Textbook of community medicine ( Preventive
and social medicine) 4th Edition by Sundarlaal.
• https://en.wikipedia.org/wiki/Hospital-
acquired_infection

76. Any Questions???
• Thank you for not asking!!!