Hospital-acquired infections are a major cause of mortality and morbidity in patients. The hospital environment, including food, air, water supplies, and medical equipment can harbor pathogens and transmit infection. Patients in hospitals are also susceptible to infection due to underlying illnesses or medical treatments. Intravenous access, urinary catheters, respiratory intubation, and surgery all provide routes for pathogens to infect vulnerable patients if aseptic technique is not followed. Maintaining clean air, water, surgical areas, and properly using and disposing of medical equipment can reduce transmission of infection in hospitals.

1. Infection in the Hospital
Environment
Aman Ullah (Lecturer)
B.Sc. Med. Lab. Technology
PhD Research Scholar (Microbiology)
Certificate in Health Professional Education
Institute of Paramedical Sciences,
Khyber Medical University, Peshawar, Pakistan

2. Introduction
• Infection is a major cause of mortality and
morbidity in patients admitted to hospital
• The most frequent types of infection are
urinary tract, respiratory, wound, skin and
soft-tissue infections, and septicaemia, which
is often associated with vascular access

3. The Environment
Food supply
• Food is usually prepared centrally in the hospital kitchens
• Patients are at risk of food-borne infection if hygiene
standards fall; this route can transmit antibiotic-resistant
organisms to immunocompromised patients who are
especially vulnerable
Air supply
• Pathogens (e.g. multidrug-resistant tuberculosis,
respiratory viruses or bacteria) may be transmitted via
theatre air supply and air-conditioning systems
• Badly maintained air-conditioning systems may be a source
of Legionella

4. The Environment
Fomites
• Any inanimate object may be contaminated with organisms
and act as a vehicle (fomite) for transmission
• This is important for doctors performing procedures on
patients with instruments that might be contaminated and
transmit infection
Water supply
• The water supply in a hospital is a complex system,
supplying water to wash-hand basins and showers, central
heating and air conditioning systems
• Legionella spp. may colonize the system in redundant areas
of pipework and cooling-tower systems are a particular risk

5. The Host
• Hospital patients are susceptible to infection
as a result of underlying illness or treatment
• Age and immobility may predispose to
infection

6. Medical Activities
Intravenous access
• This is the most frequent source of healthcare-associated bacteraemia.
• The risk of infection from any intravenous device increases with the length
of time it remains in position
• Cannula-related infection can be complicated by septicaemia, endocarditis
• The risk of sepsis can be reduced by aseptic technique at insertion
• The cannula site should be regularly inspected and this is particularly
important in unconscious patients
Urinary catheters
• Indwelling urinary catheters bypass the normal defences and provide a
route for ascending infection into the bladder
• Risks can be minimized by aseptic technique wh en the catheter is
inserted and handled

7. Medical Activities
Respiratory
• Intubation bypasses the defences of the respiratory tract
• Postoperative pain, immobility and the effects of anaesthesia
predispose to pneumonia by reducing coughing
• Inhalation of oral contents is reduced by raising the head of the bed
in seriously ill patients
Surgery
• Surgical patients often have other health problems that are
unrelated to their surgical complaint which may predispose them to
infection
• Surgery is traumatic and carries a risk of infection
• Complications of the procedure may increase risks
• The preoperative period should be short to reduce the risk of
acquiring resistant hospital organisms

8. Medical Activities
• To minimize the risk of infection during an operation,
theatres are supplied with a filtered air supply
• Staff movement during procedures should be limited to
reduce air disturbance
• Changing clothing reduces transmission of organisms
from the wards
• Impervious materials reduce contamination from the
skin of the surgical team but are uncomfortable to
wear
Antibiotic prophylaxis
• Antibiotic prophylaxis reduces postoperative infection
rates

10. Questions/Suggestions
khurramthalwi@hotamail.com