1.4 Infection Control & Healthcare Associated Infections

Question 1

The key principles and important components of infection control include the following:
• Epidemiological surveillance (and legal duty to notify authorities)
• Sanitation and hygiene
• Clean water
• Public health initiatives
• Immunisation
• Screening (including for those without symptoms)
• Management of contacts for those infected/infectious
• Isolation/Quarantine
• Adherence to policies on antibiotic use
• Surveillance of antibiotic sensitivity

• Epidemiological surveillance: Helps identify when an outbreak is occurring → allows infectious control and healthcare interventions to be better targeted
• Screening: Helps identify those who are infected/infectious to limit transmission and give treatment to prevent worsening into a chronic condition (e.g. hepatitis B leading to liver failure)
• Contact management: Helps to break the chain of transmission → prevents re-infection of index patient and prevents complications of untreated infections:
  • Important in: STIs (gonorrhoea, chlamydia), HIV, Hep A, Hep B, TB, meningitis

Meningitis is quite hard for contact tracing because of severity, helps to give ______________ if people have been exposed via droplet spread to meningococcal disease

Answer 1

rifampin, ciprofloxacin

Question 2

Airborne diseases include any disease caused by pathogens transmitted through the air (via aerosols of dust or liquids → from sources of infection or biological wastes):

• Infected aerosols can stay suspended in air currents sufficiently long to travel considerable distance (but rate of infection drops)
• Direct body contact is unnecessary for the spread to occur (via coughing, sneezing, infected aerosols, bodily secretions, biological waste)
• Often cause inflammation in the nose, throat, sinuses and lungs (URTIs present with sinus congestion, coughing, sore throats)
• Air pollution plays an important role in airborne diseases (linked to asthma)

Organisms

• Bacterial: anthrax (inhalational), chickenpox, influenza, measles, TB
• Fungal: ____________ (in students who were spelunking and bat guano became aerosolised), _______________ (valley fever)

Prevention

• Isolation in negative pressure room + N95 mask during interaction
• Handwashing/disinfection, immunisation, appropriate antibiotic use

Answer 2

histoplasmosis;

coccidioidomycosis

Question 3

HEALTHCARE-ASSOCIATED INFECTIONS Patients may develop healthcare-associated infections due to increased susceptibility to infection (because of underlying disease):
• May be infected via exogenous (from environment) or endogenous* (own flora) routes
• Also termed nosocomial/hospital-acquired infections (but healthcare is provided in many different settings)
- Endogenous infection: More common; patient’s own flora become sensitive or resistant after __________
- Exogenous infection: Infection with resistant organisms from healthcare workers or other patients
*Typically develop ______________ after admission and involve complications of necessary medical treatment (because natural barriers to infection have been breached).

Answer 3

antibiotics;

> 48 – 72 hours

Question 4

RISK FACTORS
Hospitals provide the ideal conditions for HAI and resistance to occur due to:
1. Large volume and traffic of patients in close contact
2. Very ill patients who need devices/procedures
3. Immunosuppression (disease and medical therapies)
4. Antibiotics used (exerts selection pressure for emergence and maintenance of antibiotic-resistant strains of bacteria)
5. Busy healthcare workers (if proper hand hygiene not practised)

Lungs

• __________________ (VAP)
• Healthcare-associated pneumonia (HAP)

Blood

• Central line-associated bloodstream infections (CLABSI)
• _________ (infected IV sites)

Urine
- ______________ (CAUTI)

Surgery

• Surgical site infections (SSI)
• Prosthetic infections (prosthetic joints/valves/grafts)

Answer 4

Ventilator-associated pneumonia ;

Phlebitis;

Catheter-associated urinary tract infections

Question 5

PREVENTION
There are 3 main strategies to prevent HAIs and emergence of antibiotic resistance:

Aim

• Prevent emergence of resistance: Reduce antibiotic use (regulation, agriculture, public education); Antibiotic stewardship programmes (ASP)
• Prevent transmission of resistant organisms: Hand hygiene, rapid detection, isolation
• Prevent infections from occurring: ________ insertion of catheters; Ventilator care bundles (_______________ raised)

Tools

• Surveillance: Amount of antibiotics used, Patterns and rates of resistance
• Intervention: Reducing usage of antibiotics, Reducing infections
• Research: Develop new antibiotics, Basic science (micro), Epidemiology (systems)
• Success of infection control measures is measured by ____________________.

The future direction in reducing HAIs include:

1. New antibiotics and vaccines
2. New devices (e.g. antibiotic-coated urinary catheters, copper surfaces for bed rails)
3. Rapid detection tests (point-of-care testing)
4. Better environmental cleansing and decolonisation

Answer 5

Sterile;

head of bed;

the incidence of infection after measures are put in place