Hospital Acquired Infection
Dr. Sudheer Kher
Prof & HOD,
Dept of Microbiology
Effects of HAI
• Adversely affects
performance & image
of the hospital
• Prolongation of stay
of patient
• Increase in the
morbidity & mortality
of the patients
• Increased bed
occupancy
• Hospital, community
& National resources
put under severe
strain
Synonyms & Definition
• Hospital associated infections
• Nosocomial infections
• Definition– Infections acquired by a person in the hospital, which
was neither present nor incubating at the time of
hospitalization. Such infections may manifest during
their stay in the hospital, or, sometimes after the
person is discharged from the hospital. The person
may be a patient, hospital staff or a visitor.
Historical
• Semmelweiss (1861)- Observed association of puerperal sepsis
with attendants like doctors & students. Introduced hand-washing
with chlorinated lime.
• Florence Nightingale (1863)- “The very first requirement of a
hospital is that it does its patients no harm…the actual mortality
in hospitals in large crowded city is very much higher than the
patients of the same class of diseases treated outside the
hospital”
• Lord Joseph Lister (1867)- Introduced Antiseptic Surgery with
extensive use of carbolic acid.
Factors influencing the HAI
• Age – Neonates and elderly
have highest risk due to
inefficient immunity.
• Infected patients- Community
acquired infection may
spread to susceptible
patients or attendants
• Drug resistance- Coliforms &
Staph aureus. Drug
resistance & increased
virulence
• Susceptible patients- Preexisting disease e.g.
Diabetes, Immunosuppression, prosthetic
implants, special care units.
• Surgical proceduresBypassing natural mech of
body surface. Diagnostic &
therapeutic invasive
procedures
What is so special about the
hospitals?
• Greater exposure of the
patients to infective
agents
• Inadequate ventilation,
faulty designs of the
wards & Depts
• Non-availability of
isolation rooms, toilets,
WCs.
• Overcrowding
• Spread from undiagnosed
infections at the time of
admissions
• Intimate contact between
patients, hospital staff &
visitors
• Substandard aseptic
procedures
• Poor kitchen, laundry services
• Faulty house keeping services
Sources & Transmission of HAI
• Endogenous- Patients
own flora – auto-infection
• Exogenous- Accounts for
most HAI.
– Sources :• Contact with other
patients/staff
• Environmental sources
like inanimate objects,
Air, Food & Water.
• Mode of transmission
– Contact
• Hand & Clothing
• Inanimate objects
– Air borne route
• Droplet from respiratory
tract
• Aerosol by nebulizer,
humidifiers, AC system
– Oral route- Food & water
– Parenteral route – HIV HBV
Common HAI
• UTI - Account for 40% of HAI. Associated with
catheterization, Instrumentation. Initially E. coli, Staph.
epidermidis & enterococcus later Klebsiella, Proteus,
Serratia, Pseudomonas & Providentia.
• Lower Respiratory Tract Infection: Account for 15-20%
of HAI. Leading causes of mortality. Pathogens: GNB,
Staph aureus & Strept pneumoniae
Common HAI (contd)
• Wound & Skin sepsis :- Accounts for 18% of HAI.
Common organisms – Staph aureus, Ps.
aeruginosa, Other GNBs.
• Gastro-intestinal infections :- Food poisoning,
Salmonella infections & neonatal septicemia
Control & prevention
House Keeping
• Personal hygiene & sanitation to be kept at
highest standard
• Efficient house keeping, clean bed-linens,
patient’s dress, proper bed arrangement
• Frequent mopping and periodic washing of
wards & Depts
• Each ward to have isolation facilities (separate
rooms) over and above isolation wards
Control & prevention
Dietary service
• Organized kitchen services
• Minimum handling of food
• Adequate water supply. Proper washing of
utensils, food
• Sanitation of cook house, distribution centre,
provision of food trolleys
• Periodic medical exam of food handlers,
vaccination.
Control & prevention
Linen & Laundry
• Segregation between clean contaminated &
contaminated
• Disinfection of linen before washing by chemical agents
/ boiling / autoclaving
• Transportation of linen to & from laundry
• Minimum handling while separating / counting
• Proper drying
• Decontamination & washing of blankets
• Decontamination & washing of mattresses
Control & prevention
CSSD
• Highest standard of asepsis & sterilization
should be followed
• SOP manual for standardization
• Testing of efficiency of sterilization procedures
Control & prevention
• Security – Restricting number of visitors and duration of
visits
• Engineering aspects particularly AC system
• Nursing care
• Waste disposal
– House hold non-infective
– Infected sharp
– Infected hospital waste (non-sharp)
• Antibiotic policy
Hospital Infection Control Committee
(HICOM)
• Objective
– Investigation of all HAI
– Establish surveillance programme
– Provide guidance & leadership in prevention & control of HAI
• Composition –
– Chairman – Hospital Suptdt
– Secretary – Microbiologist – Also called Hospital Infection
Control Officer
– Members – All major specialty representatives, Nursing
matron, Engineering service representative, House keeping
Dept, Dietician, CSSD.
Hospital Infection Control Committee
(HICOM)
• Role & Functions
– Establish reporting system thru’
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Nursing unit report
Individual patient report
Bacteriology reports
Autopsy report
Periodical meetings to take decisions
Lay down standards of asepsis, sterilization etc
To distinguish between HAI & Non-HAI
To prepare SOP Manual
To take decision on all reports of HAI control officer
Surveillance
• AIM : To detect & record methodically all HAI.
• Continuous monitoring helps in early detection of
outbreak, decide on incidents & trends, know the
causative agents, AST and policies
• UTI
• Lower Respiratory Tract
• Post-operative Infections
• Systemic Infections
Processing of information collected
• Information processed by infection control sister
• Weekly, monthly and annual reports prepared for the floor/
specialty / hospital for each type of HAI
• Incidence rate : No. of new patients developing HAI in a given
period compared with No. of patients discharged during the same
period
• Prevalence rate : No. of new patients and old patients developing
HAI in a given period compared with No. of patients discharged
during the same period
• Analysis helps in revealing true dimension of the problem
• Sources & reservoirs can be detected and remedial measures
taken
Interruption of transmission
• The sequence of transmission interrupted at the most
vulnerable point
– Destruction of the pathogenic agent in the carrier staff /
source patient by antibiotic / antiseptic therapy
– Isolation of patient / fomite sterilization / disinfection
– Disinfection of excreta / infected waste
– Control through washing of hands, disinfection of eqpt and
change of clothes
– Protection of susceptible host by vaccination eg tetanus, gas
gangrene
High risk procedures
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Injections
Surgical procedures
Dressing of wounds
Management of Child birth
Investigation procedures
Laboratory investigations
Dialysis
Training & Education
• Increasing awareness level
• Knowledge, skills & behavioral changes
essential
• Lectures / workshops / discussions
• Target audience – Sister I/C OT, ICUs, Labour
rooms, Post-op wards, sanitary inspectors,
CSSD, Security, dietician
Universal Safety Precautions
• They are Universal and for protection of HCW
• Routine use of appropriate barrier precautions to
prevent skin and mucus membrane exposures
when blood and body fluid contact of any patient
is anticipated
• Gloves, masks, eye shield, face shield, aprons /
gowns
Legal aspects
• Increased ALS (Average Length of Stay) in
hospital
• Increased cost to the patient / hospital / nation
• Increased morbidity / mortality
• Loss of daily earning for the patients
• Litigation against hospitals / doctors due to
negligence