Hospital acquired infections

HOSPITAL ACQUIRED INFECTIONS

Aarti SareenMSPT Honours I

Roll No. 8

Hospital acquired infection is also called Nosocomial infection or Healthcare-associated infections.

"nosus" = disease "komeion" = to take care of Nosocomial infections can be defined

as infection acquired by the person in the hospital, manifestation of which may occur during hospitalization or after discharge from hospital. The person may be a patient, members of the hospital staff and/ or visitors.

EPIDEMIOLOGICAL INTERACTION

HOST FACTORS Suppresed immune system due to Age, Poor nutritional status, severity of underlying disease, complicated diagnostic & therapeutic procedure,therapeutic,

THE AGENT

Varieties of organisms

Institutional and human

Reservoirs & their virulence

THE ENVIRNOMNETEverything that surrounds the patient in the hospital is his environment.

Other patientsHospital staff and visitorsEatablesDust and other contaminated articles

NCI

Endogenous/direct:

Caused by the

organisms that are

present as part of

normal flora of the

patient

Exogenous/indirect Caused by organisms acquiring by

exposure to hospital personnel, medical devices or hospital environment, cross-infection from medical personnel

• hospital environment- inanimate objects– air – dust – IV fluids & catheters – washbowls – bedpans – endoscopes – ventilators & respiratory equipment – water, disinfectants etc

SOURCE OF INFECTION

EXOGENOUS INFECTION SITES

The Inanimate Environment Can Facilitate Transmission

~ Contaminated surfaces increase cross-transmission ~

Exogenours Pathogens

• Mid-1980’s– Enterobacteriaceae– S. aureus– P. aeruginosa

• Mid-1990’s– Decline in

Enterobacteriaceae– Increase in gram-

positive cocci– Emergence of fungi– Recognition of viruses

Nosocomial Infections:Changing Microbiology

VirusesBacteriaFungiParasites

All microorganisms can cause nosocomial infections

Gram +veStaphylococcus aureusStaphylococcus epidermidis

Gram -veEnterobacteriaceae Pseudomonas aeruginosaAcinetobacter baumanniMycobacterium tuberculosis

BACTERIA

Pseudomonasaeruginosa

Enterococcus

Coag-neg staphylococcl

E-coli

Staphylococcus aureus

Other

COMMON BACTERIAL AGENTS

(9%)

(10%)

(11%)

(12%)

(13%)

(45%)

Viruses

◦ Blood borne infections : HBV, HCV, HIV◦ Others: rubella, varicella, SARS

Fungi◦ Candida ◦ Aspergillus

– Urinary tract infections (UTI)– Surgical wound infections (SWI)– Lower respiratory infections– Traumatic wounds and burns infections– Primary bacteraemia– Gastrointestinal tract – Central nervous system

TYPES OF INFECTIONS

Major Types of Nosocomial Infections

0

5

10

15

20

25

30

35

Overall ICU

UTIPneumoniaSWIBloodstreamOther

Richards, MJ. 1999. Crit Care Med 27; 887.

Mode of trasmission

Contact/hand borne (most common)

Aerial route or air borne Oral route

Parenteral route

Vector borne

Direct (physical contact)– Hands & clothing– Droplet contact followed

by autoinoculation– Clinical equipment

Indirect via contaminated articles– Bedpans, – bowls, jugs, – Instruments like needles, – dressings,– contaminated gloves,etc.

1. Contact (most common)

2. Airborne Transmission– Droplet respiratory secretions on surfaces– Inhalation of infectious particlese.g. (TB, Varicella)

3. Oral route4. Parenteral route5. Vector borne: through mosquitoes, flies,

rats

Pathogens transmission

The hands are the most importantvehicle of transmission of

HCAI

Why Don’t Staff Wash

their Hands(Compliance estimated at less than 50%)

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)

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

Repeat procedures until hands are clean

Routine Hand Wash

Areas Most Frequently Missed

HAHS © 1999

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

Hand hygiene is the simplest, most effective measure for preventing

hospital-acquired infections.

Surveillance

Why surveillance?

• NCI cause of morbidity and mortality• One third may be preventable• Surveillance = key factor

– an infection control measure– overview of the burden and distribution of NCI– allocate preventive resources

• Surveillance is cost-efficient!!

Objectives• Reducing infection rates• Establishing endemic baseline rates• Identifying outbreaks• Identifying risk factors• Persuading medical personnel• Evaluate control measures• Satisfying regulators• Document quality of care• Compare hospitals’ NCI rates

The surveillance loop

Event

Action

Data

Information

Health care system

Surveillance centre

Reporting

Feedback, recommendations

An

alysis, in

terpretatio

n

Considerations when creating a surveillance system

• Goal of the surveillance system (why)• Engage the stakeholders (who)• Surveillance method (what, how, when)

– definition– what to collect– how to collect (operation of system)

• Available resources

Who

• All hospitals?

• All departments?

• All specialties?

• Other health institutions?

Stakeholders

Control of NCI

There are three principal goals for hospital infection control and prevention programs:

1. Protect the patients

2. Protect the health care workers, visitors, and others in the healthcare environment.

3. Accomplish the previous two goals in a cost effective and cost efficient manner, whenever possible.

.

Goals for infection control and hospital epidemiology

To control the nosocomial infection we need to consider the chain of infection and the transmission of an infectious agent

– observance of aseptic technique – frequent hand washing especially between

patients – careful handling, cleaning, and disinfection of

fomites – where possible use of single-use disposable items – patient isolation – avoidance where possible of medical procedures

that can lead with high probability to nosocomial infection (urinary catheter)

Prevention & control of nosocomial infections

– Various institutional methods such as air filtration within the hospital

– Appropriate isolation precautions to protect patients, visitors, and HCWs.

– Surveillance for common infections, monitoring of high risk patients, and hospital area to identify outbreaks, document incidence and prevalence rate of specific infections and set goal for improvement.

Prevention & control of nosocomial infections (cont.)

Uttermost care should be taken in following services:

• House keeping• Dietary services• Linen and laundry• Central sterile supply department• Nursing care• Waste disposal• Antibiotic policy• Hygiene and sanitation

The 5 pillars of infection controlIs

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Infection Control Committee

Infection control Committee (ICC):

The hospital ICC is charged with the

responsibility for the planning, evaluation of

evidenced-based practice and

implementation, prioritization and resource

allocation of all matters relating to infection

control.

Infection Control Team

Infection Control Nurse (ICN)Infection Control Doctor (ICD)

Role of infection control teams

• Education and training• Development and dissemination of

infection control policy• Monitoring and audit of hygiene• Clinical audit