Healthcare-associated infections (HAIs) are infections acquired during healthcare and include those present after 48-72 hours of admission or after discharge. HAIs are common in low and middle income countries, especially affecting high-risk groups like ICU and neonatal patients. The major causes of HAIs are Staphylococcus aureus, Enterobacteriaceae, and resistant pathogens. Factors that predispose patients to HAIs include patient health issues, invasive procedures, and hospital environmental factors. To control HAIs, it is important to break the chain of transmission by removing infectious sources, interrupting transmission routes, and protecting susceptible patients.

1. HEALTHCARE-ASSOCIATED
INFECTIONS
DR OBAJOLOWO

2. INTRODUCTION
What is a Healthcare Associated Infection?
• An infection that occurs during the process of care delivery in a
healthcare facility that was not present or incubating at the time
of presentation.
• This includes infections acquired in the healthcare facility that
appears after discharge/leaving the HF
• Also includes occupational infections acquired by staff while
delivering healthcare services.
• Generally, for bacterial infection, It tends to show up about 48-
72 hours after HF admission/visit or may not show up till after
discharge

3. BURDEN OF HAI
• Healthcare associated Infections are common in LMICs
• Estimated Prevalence -5.7% and 19.1%.
• High-risk populations most affected -ICU and Neonates,
• Infection often device-associated -18.5% -29.3%
• ICU-acquired infection can be as high one 1 in 3 patients
• Increased length of hospital stay -5 -29.5 days
• Excess mortality in adult patients in Latin America, Asia and Africa
Allegranzi et al December 10, 2010 DOI:10.1016/S0140-6736(10)61458-4

4. SOURCES OF INFECTION
The organisms come from many possible sources, such as:
• The patients’ themselves
• Own flora –the mouth, gastrointestinal tract, vagina or the skin;
• Community acquired Infection
HCW –
• •The resident microbial flora
• •Transient bacteria carried on the hands of health care workers from one patient to
another;
Environment
• •Fomites, Surfaces,
• •Contaminated instruments, dressings, needles, infusions, contaminated disinfectants
etc.

5. SOURCES OF INFECTION
Endogenous/direct: 50%
• Caused by the organisms that are present as part of normal flora of the patient
Exogenous/indirect –15%
• Caused by organisms acquiring by exposure to hospital personnel, medical devices or hospital environment,
cross-infection from medical personnel
• Hospital environment-inanimate objects:
• air –5%, IV fluids & catheters , washbowls , bedpans, endoscopes, ventilators & respiratory equipment,
water, disinfectants etc, shared equipment
• Another Patient or HCW –35%

6. CAUSES OF HAI
Published studies of surgical and other hospital-related infections, including neonatal infections in African
countries* show a pattern of pathogens similar to those seen globally:
• Staphylococci
• Enterobacteriaceae (e.g., Klebsiella, E. coli,Salmonella)
• Pseudomonas spp
• Antimicrobial resistant pathogens, including Methicillin Resistant Staphylococcus Aureus
• ESBL-producing Gram negative organisms
• Viruses: HBV, HIV, respiratory viruses etc
• Endemic prone- Lassa fever, Ebola, TB, cholera
*Botswana, Cote d’Ivoire, Ethiopia, Ghana, Kenya, Nigeria, Senegal, South Africa, Tanzania, Zimbabwe

7. CAUSES OF HAI
Most common gram positive organisms –
• •Staph aureus and Staph epidermidis and Enterococcus faecalis
• •surgical and skin sepsis and IV therapy
• •Strept pneumoniae-respiratory tract infection
Most common gram negative organisms
• •E. coli–single most frequent bacterial spp.
• •Majority of infections associated with surgery or instrumention of the UTI or GIT.
• •Others include Klebsiela spp., Proteus, Pseudomonas, Serratia spp and
Bacteroidesspp, Acinetobacter spp

8. FACTORS PREDISPOSING TO DISEASE
Human factors
• Administrative
• Practices and Procedures
• HCW, Patients and Visitors
• Instrumentation
Environment
• Design of Facility
• Ventilation
• Access to water
• Sanitary Facilities
• Pests

9. CYCLE OF INFECTION
Factors involved in the spread of disease and all must
be present to transmit infection
1. Pathogenic organism
2. Reservoir of infection
3. Portal of Exit
4. Means of Transportation/transmission
5. Portal of Entry
6. Susceptible Host

10. CHAIN OF INFECTION
These are necessary elements to complete the chain
Primary links
• Susceptible host: person, animal, or insect capable of being infected by an agent
• Infectious agent: bacteria, viruses, fungi or parasites with ability to cause infection
• Mode of transmission: mechanism an infectious agent uses to move to a host and survive in the
environment
Secondary links
• Reservoir: person, animal, or environment where an infectious agent can survive and multiply
• Portal of entry: a way an infectious agent can enter the host
• •Portal of exit: a way an infectious agent can leave the host

11. MODE OF TRANSMISSION
• Mode of transmission
• Contact -(most common)
• Air-borne
• Droplet
• Parenteral route
• Vector borne

12. TYPES OF HAI
• Catheter –associated Urinary Tract Infection
• Surgical site Infections
• Soft tissue infections
• Catheter associated Blood stream infections
• Ventilator associated Pneumonia
• ICU associated infections
• Wound Infections

13. FACTORS PREDISPOSING TO INFECTION
HOST FACTORS
• Immune status
• Extremes of age
• Poor nutritional status,
• severity of underlying disease,
• Invasive procedures
• complicated diagnostic & therapeutic procedures
• Vaccination status,
THE AGENT
• Virulence of the organisms
• Infective dose
• Timing
THE ENVIRNOMENT
• Everything that surrounds the patient in the hospital is
his environment.
• Other patients
• Hospital staff and visitors
• Food, Water source,
• Equipment, bed rails, fomites,
• Dust and other contaminated articles

14. Control of HAI: Breaking the Chain of
Transmission
• To control HAIs we need to break the chain of
transmission
• Remove the reservoir/organism, interrupt the
mode of transfer, prevent acquisition by new
host
•Source control –
• Isolation procedures, Wound dressing, removing
infected items
Break Transmission
• Gloves, Masks, hand hygiene
• Cleaning disinfection and sterilisation
Protect the susceptible host–Protective isolation,
vaccination

15. CONCLUSION
• Any organism can cause an HAI in the susceptible host
• Every one can be susceptible to HAI
• IPC works
• Keep your patient safe
• Keep your hospital safe
• Keep yourself safe