2. Introduction
• The hospital and other institutions of health care
practice provide a special setting for the interaction
of the agents of infection and the hosts, i.e. patients
and health care workers( HCWs).
• The term hospital infection and control has emerged
recently to a full,scientifically tested programme of
surveillance,prevention and control of infections not
only in the hospital but also beyond. The
microbiology laboratory has become an integral
part of this discipline contributing to different
aspects of surveillance, prevention and control.
3. Definition
• The term hospital acquired infection (HAI)
(syn. Nosocomial infection) is applied to any
clinical infection that was neither present nor
in its incubation period when the person
entered the hospital. The person may be a
patient or a HCW. Such infections are also called
as hospital associated infections. As health care
is now being provided in ambulant patients,the
term health care- associated infections is more
appropriate.
4. Determination of HAI
• The incubation period of the specific
infection ,to call it as nosocomial or not ,
must be considered because the infection
may manifest when the patient is in the
hospital or after the patient has been
discharged. The majority of HAIs become
evident 48 hours or more following
admission. However, it may not become
clinically evident until after discharge.
5. Prevalence of HAI
• The overall reported incidence of post operative
wound sepsis in different hospitals in India
varies from 10 to 33%. Western studies indicate
the incidence of HAI in the range of 3-10%
with an average of approx 5%. The most
commonly reported sites of infection are urinary
tract(42%),SSI(23.8%), respiratory tract(10.5%)
and blood stream infection(4.8%). In the adult
ICU, most common HAIs are LRTI. In the PICUs
superficial sites( skin, umbilicus and cinjunctiva)
and bacterimia predominate. Meningitis is
much more common in PICU than adult ICU.
6. Unique features of the pathogens
involved in HAIs
• Relative resistance to antibiotics and hence
difficult to treat.
• Relative virulence when compared with
normal endogenous and environmental flora.
• Capability to withstand variations in the
environmental conditions.
• Highly susceptible patients like patients with
extremes of age,those on broad-spectrum
antibiotics,chemotherapeutic agents and those
in the ICUs.
7. Consequences of HAI
• Increased morbidity of patients
• Increased length of stay in the hospital,which
leads to increase in expenditure and the
pathogens causing HAI are difficult to treat.
• Mortality, which is most commonly due to
pneumonia ,primary bacterimia and meningitis.
• Patients act as reservoir of infection.
• So, there is an urgent need to control infection.
8. Steps to Reduce/Stop the spread of
infection in hospital
• Understand the sources of infection and
how it spreads.
• Remove the source of infection by treating
the infected patient/proper cleaning/
disinfection/ sterilisation
• Learn the infection control procedures to
block transmission.
• Teach infection control procedures to others
• Know the special infection risks of your job.
9. Microbial causes of HAI
• HAI can be caused by a range of bacteria, viruses,fungi and
parasites.The bacterial sp. Predominantly involved in HAI
has been changing over the years. Till the early part of
Second World War, the main concern was S.pyogenes
which was handled once Penicillin was introduced. Upto
1960, S.aureus was the major concern. From 1960
onwards Gram negative aerobic bacilli have
predominated the hospital setting. More recently, it is the
Gram positive bacteria that have been restored as the
primary cause of HAI,involving
S.aureus,CONS,enterococci and some corynebacteria. It is
perhaps the availability and the use of antibiotics that
alter and influence the circulating bacterial agents.
10. Bacterial sp. Associated with HAI
Gram positive
bacteria
Gram Negative
Bacteria
Viruses Fungi Parasites
Staphylococcus
aureus,
Coaugulase
negative
staphylococcus,
Streptococcus
pyogenes,
Streptococcus
agalactiae
,enterococci ,
Corynebacteria
sp( JK group) ,
C.difficile
Pseudomonas
sp, Klebsiella
sp,
Acinetobacter
sp
Enterobacter
sp, Escherichia
sp, Proteus sp
Salmonelle-
food poisoning
Rotavirus,Norw
alk agent,
enteroviruses,
herpes group
of viruses esp
CMV. Influenza
virus.
Hepatitis A,B,C
HIV
Candida
albicans and
other candida
sp e.g. C.
tropicalis
Cryptosporidiu
m sp
11. Viruses are not important part of HAIs except in
neonatal,paediatric and immunocompromised
patients.occasionally the above mentioned viruses
have been involved.
• The incidence of opportunistic fungal infection due to
candida sp is on a rise. This is largely due to medical
and surgical advances leading to a large no of severely
immunocompromised hospitalised patients and use
of broad spectrum antibiotics.
• Among the parasitic causes Cryptosporidium is an
important cause of diarrhoea in AIDS patients.
12. Sources and mode of spread of HAI
Sources of infecting organism
↓ ↓
Endogenous: infection from the
patient’s own flora,which at the time
of infection may include organisms
brought into the hospital at admission
or the organisms acquired
subsequently during hospital stay
Exogenous: infection from
another patient, hospital
staff,visitor,relative,or the
Inanimate environment of
The hospital such as air,dust
Equipments,instruments,
Solutions,lotions,linen etc.
13. Sources of HAI
• Source may be Exogenous or Endogenous. In either case
,the organism may invade the host’s tissues spontaneously
or introduced into them by surgery,instrumentation or any
other invasive procedure.
• Some bacteria survive well in dry environment
sites,e.g.Gram-posotive cocci. On the other hand some
bacteria survive well in moist situations. Of those, some
survive without multiplication in wet atmosphere,e.g.E.coli
and Klebsiella sp., while there are others that not only
survive but also multiply in wet situations,
e.g.Pseudomonas sp.
• Main sources of Staph & Strepto inf are mouth,throat,nose
skin and their secretions.Main route of inf is air. Main
reservoir of VRE is hospitalized patients with GI carriage.
15. • Most common mode of transmission of VRE
is by HCW’s hands transiently contaminated
with the organism.Transmission may also
occur through contaminated medical devices.
The main source of GNB are faeces, uine,
contaminated devices,fluids( including
disinfectant preparations) food and medicine
and the main routes of inf are contact(direct
and indirect) and inoculation.
16. • Extensive use of antibiotics and antiseptics in the
hospital, particularly in the ICUs exerts selective
pressures on endogenous and exogenous
misroflora.As a result , only the organisms that
carry and express resistance determinants
survive. This also results in the emergence of
multiple drug resistant organisms.This along
with the fact that the host is extremely
susceptible, makes the treatment of such
infections a continuing challenge.
17. Chain of Infection
• Source/ Reservoir of Microorganism---
infected person or other source----- mode of
transmission– hands of personels, instruments
clothing,coughing, sneezing , dust etc.----
Point of entry---natural orifices like mouth,
nose,ear,eye,urethra,vagina,rectum. Artificial
orifices like tracheostomy,ileostomy,colostomy
Skin breaks either as a result of accidental
damage or deliberate inoculation/incision---
Susceptible host.
18. Control of HAI
• It Is important because :
1. It helps to reduce the mortality and
morbidity of patients.
2.It cuts down the expenditure incurred
Infection control committee(ICC) in a hospital is the
central decision and policy making body. Its members
include representatives from different clinical
departments with active participation of medical
microbiologist.Together they help to establish
microbiologically safe conditions in the hospital ,
ensuring safe practices in the day-to-day care of
patients. Infection control nurse(ICN) is an essential
member of ICC and plays a vital role.
19. Role of ICN
• Prevent cross infection in hospitals
• Provide clinical surveillance of infection
• Effectively liaison with all staff
• Develop infection control policies
• Train hospital staff about infection control
procedures.
• Emphasizing on the implementation of infection
control procedures.
• Investigate suspected outbreaks.
20. Surveillance
• Most important and laborious task is
surveillance. It is defined as the continuing
scrutiny of all aspects of occurrence and
spread of a disease that are pertinent to
effective control.It implies a continuous process
rather than an investigation undertaken for a
specific outbreak. When continuous
surveillance is not possible, the point
prevalence study is recommended.This method
identifies active NI at the time of a visit to each
ward.
21. Components of Surveillance
• 1. Data collection
• 2.Analysis
• 3. Interpretation and reaction
• The ICC largely relies on the surveillance
data for issuing policies.
22. Principles of infection control
• 1.Remove the source of infection by
treating the patient and following proper
cleaning/disinfection/sterilization procedures.
• 2. Block transmission of microorganisms
from various sources to suscetible patients
and HCWs.
• 3. Enhance the resistance of patients either
by immunisation or by antibiotic
prophylaxis as may be appropriate.
23. Infection control Procedures: steps of
Hand Washing
• 1. Hand washing : is the single most effective
measure in infection control
24. A.HAND WASHING
Hand washing is the single most effective
precaution for prevention of infection
transmission between patients and staff.
Hand washing with plain soap is
mechanical removal of soil and transient
bacteria (for 10- 15 sec.)
Hand antisepsis is removal & destroy of
transient flora using anti-microbial soap or
alcohol based hand rub (for 60 sec.)
25. When to wash hands
• Before performing invasive procedure
• Before taking care of particularly susceptible patients such
as those who are severely immunocompromised and
newborns.
• Before and after touching wounds.
• After contact with mucous membranes, blood or body
fluids, secretions or excretions.
• After touching inanimate sources such as urine measuring
devices or secretion collection apparatus.
• After taking care of an infected patient/patient colonised
with multidrug resistant bacteria.
• Between contact with different patients in high risk units.
26. Procedures contd
• 2.Practice barrier nursing techniques(use
disposable gloves,gowns,goggles and masks
whereever needed.)
• 3.All procedures and handling of potentially
infectious material should be performed carefully
to minimise splashing or the formation of
droplets and aerosols.
• 4.Avoid spills. In case it occurs,it should be
covered with absorbent material and then pour
disinfectant (1% hypochlorite/bleaching powder
14 gm per litre)over it and leave for 10 minutes.
27. Procedures contd
• 5.Extraordinary care must be taken to avoid
accidental injury from sharp instruments
contaminated with potentially infectious
material.
• 6. contact of open skin lesions with infectious
material must be avoided.
• 7.Ensure that proper segregation of infectious(
red/yellow/blue bucket) and noninfectious waste
is done before final disposal.Waste buckets
should be lined by colored plastic bags.
28. WHO 5 Moments of Hand Hygiene:
•Before touching a patient
•After touching a patient
•After touching blood & body fluids
•Before doing any aseptic procedure
•After touching the patient’s surroundings
29. Procedures
• 8.All articles contaminated with blood,if disposable,
should be discarded in infectious waste disposal plastic
bags. If disposable bags are not available, these articles
should be discarded in a container with sodium
hypochlorite solution with CAUTION label.
• 9.Disposable needle and sharp instruments should be
discarded in puncture proof container with sod.
Hypochlorite solution after destroying the needle along
with the hub.
• 10.Reusable items should be disinfected first,before
cleaning and sterilising.
30. Procedures Contd
• 11.Ensure adequate processing and safe use of medical
devices and other patient care objects
a)Critical patient care objects: (i)Surgical instruments and
devices;trays and sets(sterilised in the hospital):-
Thoroughly clean objects and wrap or package for
sterilisation. Monitor time-temperature chart of steriliser.
Use bacterial spore to monitor steriliser. Inspect package
for integrity and for exposure of sterility indicator before
use. Most items must be reautoclaved after 72 hours of
storage,if not used in this period.
(ii)Intravenous fluids,trays and sets ( purchased as sterile)
Store in a clean area. Inspect for integrity before use. Use
before expiry date. Culture only when indicated.
31. • 11(b)Semicritical patient care objects: (i)
Respiratory therapy equipment and instruments
that touch mucous membranes: sterilise or or
follow high-level disinfection. Store in a clean
area. (ii)Airways and endotracheal tubes :
preferably rely on single-use disposable type.
• 11(c) Noncritical patient care objects
(i) Water used for haemodialysis fluids : assay
water and dialysis fluid monthly.Water should not
have more than 200 bacteria per mL and dialysis
fluid not more than 2000 bacteria per mL
32. • 11( c) ( ii) Bedding : Bedsheet; change on
alternate days or whenever soiled. Mattresses:
cover with water impermeable cover, wash it
with detergent and water at bed making. Wipe
with 2% phenol/2% carbolic acid/ 1%
hypochlorite after detergent wash if
contaminated. Fumigate for heavy contaminat
Pillow : Treat in the same way as mattresses.
Bedpans/Urinols: First clean by soap and running
water followed by 30 minutes in 1% bleach//2%
Lysol/2% phenol
33. Procedures
• 12. Chemical sterilising agents should not be
used beyond its expiry date.
• Visitors should be reduced to a minimum. Gowns
and change of slippers should be made
mandatory before entering the ICU.
• There should be no
eating,drinking,smoking,applying
cosmetics,wearing rings,bracelets etc in the place
of work.
• No paper work should be done on potentially
contaminated surfaces.
34. 16. Proper cleanliness of working area
• (a) Cleaning of mops: Change daily for OT. Others: Wash in
detergent water thoroughly and dry in sun after use.Immerse in 2%
phenol overnight after washing in case of heavy
contamination.Rinse, dry and use.
• (b) Buckets: Wash, dry and keep inverted.
• (c) Cleaning of theatre: Same as above.In addition ,clean twice a
day with 2% phenol using two bucket system: clean water and dirty
water.
• (d) Rooms and corridors: Cleaning to be done once in every shift.
• (e) Theatre light: Damp dusting with 0.1% hypochlorite/5% savlon
followed by coating with liquid paraffin to trap dust.
• ( f) Walls and ceilings: Damaged surfaces should be kept
repaired.For walls: wet mopping with 2% carbolic acid /5% lysol is
recommended.
35. 17.Procedure contd
• Fogging can be done in intensive care areas or
other parts of hospital as part of terminal
disinfection when advised by ICC. This involves
the use of hydrogenperoxide vapour(HPV)
‘fogging’ by novel ‘no-touch’ automated room
decontamination technologies. HPV fogging can
be an essential intervention to rapidly reduce
transmission of health care associated pathogens.
This has replaced the traditional formaldehyde (
fumigation procedure) due to safety and efficacy
concerns.
36. • 18. Guideline for collection of blood sample for
culture: Discussed with sample collection
• 19.Protection against blood-borne infection will
be discussed with ‘Occupational hazards’.
• 20.Involvement of the patient and patient’s
attendants in prevention and control of infection
should be encouraged.
• Follow aseptic techniques and assertain that
others also follow it. Infection prevention and
control are a team effort.
37. • To sum up ,it is important to remember what
Florence Nightingale( 1862) wrote on her
experiences on hospital infection: It may seem
a strange principle to enunciate as the very
first requirement in a hospital that it should
do the sick no harm.
38. Infection Control Manual
Every Hospital should have a nosocomial
infection prevention manual compiling
recommended instructions and practices for
patient care.
This manual should be developed and updated
in a timely manner by the infection control
team.
It is to be reviewed and accepted by infection
control committee.
39. Why HAI are Increasing?
• 1) Increase in compromised pts
• 2) Interhospital / ward transfer
• 3) Antibiotic resistant superbugs
• 4)Increasing workload
• 5) Staff pressures
• 6) Lack of facilities
• 7) Lack of compliance with infection control
procedures.
8) HAI is preventable and can be reduced by 10-
30%.
