Download nosocomial infection

NOSOCOMIAL INFECTION
Dr Sathya Anandam
Hospital infection is generally defined as any infection
acquired while in the hospital, occurring 48 hrs. or more
after admission and up to 48 hrs. after discharge.
Sources of Hospital Infection:
o Exogenous Source
- from another patient-cross infection
or from the hospital environment.
o Endogenous Source
- another site within the patient
(self or autoinfection.)
Common Hospital Infections:
o Urinary Tract Infection -28%
o Surgical Wound Infection -17%
o Respiratory Tract Infection -17%
o Bacteremia –due to IV devices 16%, others 20%
Important causes of hospital infections:
• In pre-antibiotic era the majority of infections were
caused by Gram positive organisms particularly S.
pyogenes and S.aureus.
• But after the advent of penicillin, Gram negative
organisms such as E. coli and P. aeruginosa
emerged as an important pathogen.
• More recently broad spectrum antibiotics and
invasive techniques resulted in VRE, MRSA,
multidrug resistant Gram negative organisms
including ESBL producers are the common causes of
hospital infection.
Source and Route of Spread of Hospital
Infection:
o Health care personnel
o Patients
o Inanimate Environment
The Transmission Cycle:
patients( colonised and infected)
antibiotic
MRSA
pressures
hands
environment
Staphylococcal carriers:
• S.aureus colonizes many sites in the human body of
which the anterior nares are the most common carriage
site.
• About 30% of the population carry S. aureus, out of
which 20% are colonized and 10% are transient carriers.
• Some people have an inherent tendency to always carry
S. aureus and they recolonise very quickly after
eradication attempts.
The predisposing factors:
• Age - patients at extreme ages.
• Underlying diseases – liver disorder, diabetes, renal
failure etc.
• Specific medicaments – cytotoxic drugs, steroids, post
transplant immunosuppression.
• Invasive procedures
– surgery, intravenous and urinary
catheters, peritoneal dialysis.
Consequences of hospital infections:
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Serious illness or death
Prolonged hospital stay
Drug resistance
Economic burden
Infected patient becoming source for others in the
hospital and community.
Prevention of Hospital Infection:
Three main strategies:
o Excluding the sources of infection from the hospital
environment.
o Breaking the chain of infection by interrupting the
transmission of infection from source to the
susceptible host.
o Enhancing the host’s ability to resist infection.
Standard Precautions :
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Hand Washing
Gloves
Mask, Eye Protection, Face Shield
Gown
Environmental Control
Appropriate sharp disposal
Transmission based precautions:
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Air borne precautions
Droplet precautions
Contact precautions
• Cleaning has two main functions.
 non-microbiological : to improve the appearance.
 microbiological
: to reduce the number of microbes,
: to reduce the risk of infection for
people in contact with that object.
• usually a great emphasis is given to the cleaning of floors
and toilets.
• the role of near-patient hand-touch sites ( bed rails, bedside
lockers, infusion pumps door handles, nurse call button etc.)
in transmission of infection has not been given importance
which should be considered.
Hospital Infection Control Program:
• Detect and monitor hospital acquired infection and to
prevent & control their spread.
• Establishment and monitoring of policies and
procedures designed to prevent infection (eg.catheter
care policy, antibiotic policy etc.)
• The investigation of outbreaks.
Infection Control Committee:
• Infection control officer-Microbiologist or physician
• The infection control practitioner (often a nurse with
special training)
• The hospital epidemiologist (usually an infectious
disease physician)
• The members of the committee would also include
representatives of all the major specialities, house
keeping, CSSD, and hospital administration.
The role of infection committee:
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Surveillance
Policy development
Outbreak investigation
Education and training of the health care personnel
Hospital employee health.
Vijay Pratap Raghuvanshi
M.Phil & MHA
Vijay Pratap Raghuvanshi
M.Phil & MHA