Hospital Acquired Infection by Dr. Rakesh

1. Hospital Acquired Infection
By Dr. Rakesh Prasad Sah
Associate Professor, Microbiology

2. Hospital Acquired
Infection
• An infection acquired by a patient during hospital
care which was neither present nor incubating at
the time of admission.
• Acquired after 48hrs of admission and patient was
not admitted in hospital for management of this
infection.
• Also called as “Nosocomial infection”.
• Such infections  may become evident during their
hospital stay or sometimes after discharge.

3. • HAI also include following
– Occupational infections
among healthcare personnel
(e.g. infections transmitted
through needle stick injury).
– Infections in neonates acquired
during birth.

4. Factors affecting HAI
• Immune Status
• Hospital environment
• Hospital organisms
• Diagnostic or therapeutic interventions
• Transfusion
• Poor hospital administration

5. Factors affecting HAI
• Immune Status
– Impaired defence mechanism due to pre-existing ds e.g.
Diabetes, immunosupression and prosthetic implants

6. Factors affecting HAI
• Hospital environment
– is heavily laden with a wide variety of pathogens.
– Pathogen may be present in air, dust, water, food or
antiseptic lotions.
– Equipment may be contaminated.
– Bedding, linen and utensils may acts as fomites.
– Patient shed the organisms from their bodies while hospital
personnel spread these organism through their hands and
clothes.

7. Factors affecting HAI
• Hospital organisms (Drug Resistance)
– Usually multidrug resistant.

8. Factors affecting HAI
• Diagnostic or therapeutic interventions
– E.g. insertion of urethral or intravenous
catheters  introduce infection.
– Most of these infection due to
endogenous flora of patient.

9. Factors affecting HAI
• Transfusion
– Blood, blood products and intravenous fluids  if not
properly screened  can transmit many infections.

10. Factors affecting HAI
• Poor hospital administration

11. Sources
• Endogenous sources
• Exogenous sources
– Environmental
sources
– Health care
workers
– Other patients

12. • E. coli
• SARS-CoV-2 (COVID-19)
• Candida albicans
• Clostridium difficile
• Blood borne (transfusion and Needle stick injury)
• HIV
• Hep-B
• Hep-C
Microorganisms

13. Mode of Transmission
• Contact
• Droplet
• Airborne

14. Mode of Transmission
• Contact
– Hands and clothing
• Hands of hospital staff are an important vehicle of spread of infection. E.g.
Staph aureus and Str. pyogens.
– Inanimate Objects (endoscope, bronchoscope, cystoscope)
• not properly disinfected  may transmit pathogenic organism.
(Pseudomonas aeruginosa)

15. Mode of Transmission
• Airborne
– Droplets (By inhalation)
– Dust (Bedding, floors, exudates dispersed from a wound during
dressing) and skin by natural shedding of skin scales (measles,
staphylococcus sepsis)  may contribute in spread of infections
e.g. Pseudomonas aeruginosa, Staph. aureus
– Aerosols

16. Mode of Transmission
• Airborne
– Aerosols produced by nebulizers, humidifiers and air conditioning
apparatus transmit certain pathogens to the respiratory tract. E.g.
legionellae pneumophilla.

17. Mode of Transmission
• Oral Route
– Hospital food may contain certain antibiotic-resistant bacteria
(Pseudomonas aeruginosa, E. coli, Klebsiella spp and others) 
may colonise the intestine  later cause infection in susceptible
patients.

18. Mode of Transmission
• Parenteral Route
– Introduction of disposable syringes and needles, transmission of
infection by parenteral route has been infrequent.
– Certain infection may be transmitted by blood transfusion or
tissue donation, contaminated blood products (factor VIII) and
contaminated infusion fluids.
– E.g. Hepatitis B and HIV are two viruses

19. Types of Healthcare Associated Infections (HAI)
• Catheter Associated Urinary Tract Infection
(CAUTI)
• Ventilator Associated Pneumonia (VAP)
• Central line Associated Blood Stream
Infection (CLABSI)
• Surgical Site Infection (SSI)
Are associated with
devices used hence
named as Device
associated
infections (DAIs)

20. Catheter Associated Urinary Tract Infection (CAUTI)
• UTI accounts for majority of the healthcare
associated infections (HAIs).
• Usually assocaiated with catheterisation
• UTI associated with catheterisation is
named as catheter associated urinary tract
infection (CAUTI).

21. Infection can be prevented by strict asepsis during catheterization. Indwelling
catheter should be used only when its use is unavoidable.

22. Predisposing Factors
• Extreme of age
• Females
• Catheterization for >2 days
• Severe underlying diseases

23. Ventilator Associated Pneumonia (VAP)
• Second most common cause of HAIs after UTI.
• Unconscious patients and pulmonary ventillation
may lead to nosocmial pneumonia.
• Major pathogens
– Staph. Aureus
– Klebsiella spp
– Enterobacter
– Serratia
Proteus
E.coli
Pseudomanas aeruginosa
Acinetobacter
Legionella pneumophila
Respiratory viruses

24. Risk Factors
• Device related: Endotracheal intubation
• Prolonged ICU stay: More risk of hospital acquired multidrug resistant
organisms.
• Semiconscious state: Aspiration of oropharyngeal flora.
• Poor infection control practices e.g. poor hand hygiene.

25. Central line Associated Blood Stream Infection (CLABSI)

26. Central line Associated Blood Stream Infection (CLABSI)
• Fourth common cause of HAIs.
• May be due to consequences of infection at any sites but is generally
caused by infected intravenous cannulae.
• Also named as central line associated blood stream infections
(CLABSI).
• Common pathogens:- Gram negative bacilli and Staph epidermidis

27. Risk Factors
• Extreme of age
• Low immunity
• Malnutrition
• Burns or bed sore
• Prolonge ICU stay
• Presence of central line
• Poor infection control practices e.g. poor hand hygeine

28. Surgical Site Infection (SSI)
• Infection develops at surgical site within 30 days of surgery
(within 90 days of cardiac, breast and joint surgeries) is called
Surgical site infections (SSI).
• Incidence of post-operative infection is higher in elderly patients.
• Predominant pathogen
– Staph aureus
– Then Pseudomonas aeruginosa and then E. coli, Proteus,
Enterococci and CONS.

29. Classification
• Clean wound :- Skin flora is the major pathogen. E.g. Staph. aureus
• Clean-contaminated wound
• Contaminated or dirty wound

30. Others HAIs
• Gastrointestinal Infections
• Burns

31. Diagnosis and Control
• By routine bacteriological methods, Direct smear examination, Culture, Sensitivity
testing
• Samples from possible sources of infection such as hospital personal, inanimate
objects, water, air or food.
• Control of hospital infection  should be a permanent ongoing activity. Eg.
– Sources of hospital outbreaks
– Nasal carriage of staphylococci in hospital staff or Pseudomonas
– Causes infection may be a defective autoclave (therefore, sterilization
techniques have to be tested)

32. • Unfortunately, in many hospitals  infection control is attempted by use of
more and more antibiotics  lead to selective colonisation by MDR pathogens.
• Concern about transmission of the HBV and HIV led to the introduction of
“Universal precautionss” to minimize the infection in medical laboratory
workers and health care personel.

33. Prevention
• Transmission of infection can be controlled by regular proper washing of hands, disinfection
of equipments and change of working clothes.
• Administration of antibiotic therapy to carrier staff or source patient to destroy the
pathogenic agents.
• Proper sterilization and disinfection of the inanimate objects should be done  helps to
control the source of infection.
• Disinfection of excreta and infected material is necessary to control the exit point of
infection.

34. • Use of sterile dressings, surgical gloves, face masks and I/V fluids further contribute in
control of infection.
• Preoperative disinfection of the patient’s skin.
• Rational antibiotic prophylaxis.
• Proper investigation of hospital-associted infection and the treatment of such cases.
• Broadly prevention can be done by
– Standard precautions
– Transmission based precautions

35. Prevention of HAIs
Standard Precautions
• Include a group of infection prevention practices  apply to all patients,
regardless of suspected or confirmed infection status in any setting in which
healthcare is delivered
• Rationale: all blood, body fluids, secretions(except sweat), excretions, non-intact
skin, and mucous membranes may contain transmissible infectious agents.

36. Components of Standard Precautions
• Hand hygiene
• PPE (Personal protective equipment)
• Biomedical waste management
• Spillage cleaning
• Disinfection of patient care items (disinfected before reuse)
• Safe injection practices
• Environmental cleaning (Surface and floor in OT, ICUs, wards etc)
• Sharp handling (handled with extreme care)
• Respiratory hygiene and cough etiquette

37. WHY is hand hygiene required?

38. Hand Hygiene
• Main source of transmission of infections
• Most important measures to avoid the transmission of microbes.

39. Hand hygiene
• Hand hygiene
– Hand rubbing
– Hand washing
• “My five moments of hand hygiene”
– Hand rub with alcohols
– Hand wash with soap and water

40. “My five moments of hand hygiene”
1. Before touching a patient
2. Before a procedure
3. After a procedure or body fluid exposure
4. After touching a patient
5. After touching a patient’s surroundings

41. In addition to the above, hand hygiene should be
performed in the following non-clinical situations
1. Before eating/handling of food/drinks (whether own or patients)
2. After hands becoming visible soiled
3. After visiting a toilet
4. After blowing/wiping/touching nose or mouth
5. After putting on and removing personal protective equipment (PPE)
6. After handling laundry/equipment/waste

42. Hand Rub with Alcohols
• They are a suitable and effective alternative to hand washing with
soap and water, provided the hands are visible clean.
• If the hands are soiled, they should be washed using a soap and
water first.
• Alcohol hand rubs must not be placed near electrical sockets,
switches or devices.
• Alcohol must be thoroughly rubbed in until dry before undertaking
any clinical procedure

45. Hand wash with soap and water
Alcohol hand rubs are not suitable:
1. When hands are visibly soiled
2. After using a rest room

47. • Video

48. Personal Protective Equipments (PPE)

49. STEP OF DONNING
1. Hand Rub with sanitizer
2. Wear shoe cover ( one at a time)
3. Wearing a pair of gloves ( 1st pair)
4. Wear mask (n95)
5. Wear goggles
6. Wear jumpsuit
7. Wear face shield
8. Wear last pair of gloves (2nd pair)

50. STEP OF DOFFING
1. Hand hygiene with sanitizer
(3ml)
2. Remove the 1st pair of gloves
(1st pair)
3. Hand hygiene with sanitizer
4. Remove the face shield
5. Hand hygiene with sanitizer
6. Remove the jumpsuit
7. Perform hand hygiene
8. Remove the shoe cover
9. Perform hand hygiene
10. Remove the goggles
11. Perform hand hygiene
12. Remove n95 mask
13. Perform hand hygiene
14. Remove last pair of gloves (2nd
pair)
15. Perform hand hygiene
16. Wear 3 ply mask
17. Leave the area .

51. Respiratory hygiene/cough etiquette
• Avoid patient careare as if you havea respiratory infection. Stay home if
possible. Weara mask during hospitalvisits.
Wash hands with soap and water

52. Respiratory hygiene/cough etiquette
• If no tissues are available, cough or
sneeze into the inner elbow rather than
the hand
• Surgical masks can be used on the
coughing person when tolerated and
appropriate

53. Respiratory hygiene/cough etiquette
• Spatial separation, ideally > 6 feet, of persons with
respiratory infections in common waiting areas when
possible

54. The Key -
always be alert
Put on protective
gear when
needed

55. Spill management for Blood and Body
Fluids
• Bring the spill kit to the site of spillage
– wear PPE (gloves, gown)  put ‘no
entry’ sign board near the spill area.
• Small volume (<10ml)
– Wipe up spill immediately with absorbent
material and discard into appropriate bin
– Wipe the area with 10% sodium
hypochlorite and allow it to dry
– Remove PPE and perform hand hygiene

56. • Large volume (>10ml)
– Place disposable paper towels over
spills to absorb the spillage and then
pour 10% sodium hypochlorite on the
top of absorbent paper towels and
leave for 15mins
– Remove the absorbent papers; put
fresh disposable paper towels to clean
the area and then discard these into
appropriate waste bin
Spill management for Blood and Body
Fluids

57. Transmission Based Precautions
• From other PPT

58. Hospital Infection Control Policy
• Every hospital must have an effective hospital infection control committee (HICC)  responsible
for the control of HAIs.
• HICC Constitution
– Medical Superintendent (Chairperson)
– Microbiologist (hospital infection control officer)
– Heads of all clinical departments and blood bank
– Microbiologist
– Medical record officer
– Chief of nursing services
– Infection control Nurse
– Chief of all supportive services (OT, dietetics, laundry, house keeping etc)  invited members.
Members

59. Functions of HICC
• ICC must meet at least once every month to
– formulate and update policy on matters related to hospital infection and
– manage outbreaks of HAIs.
• The committee will review
– Infection control activities of the hospital
– Emergence of drug resistance
– Use of different antimicrobial agents
– sterilization and disinfection procedures
– Hospital environment
– Incidence and types of infections and antimicrobial sensitivity patterns of the prevalent
pathogens.

60. • The HICC supervises the implementation of hospital infection control program. The
various functions include:-
– HAI surveillance
– Investigating and controlling hospital acquired infections.
– Antimicrobial Stewardship program
• Develops antibiotic policies
• Monitor the antibiotic usage
– Conduction of teaching sessions for various healthcare workers.
– Review and update the hospital infection control guidelines from time to time.
– Vaccination of staff and also to monitor the matters of needle stick injury.
– Outbreak management.