Burden of occupationally-acquired infections among healthcare workers

Background: The number and type of infections among healthcare workers acquired through their work is poorly understood.  Surveillance has focused on tuberculosis, but workers are at risk for many other infections.

Objective: To quantify the annual number of infections acquired by healthcare workers because of their work. Seven infectious diseases were considered in hospitals, emergency departments, ambulatory care, long-term care and home care settings.

Methods: A quantitative risk analysis approach was used.  The annual number of occupational exposures was estimated from the community burden of infectious disease and healthcare utilization.  A compartmental model was used to estimate the dose of pathogens received by a healthcare worker during an occupational exposure.  Dose-response functions were used to estimate the probability of infection during an occupational exposure.  The probability of infection during an occupational exposure and the number of occupational exposures was integrated with the number of healthcare workers to estimate the annual burden of infection.

Results: Detailed results will be presented for influenza, and summarized for other infectious diseases.  If all workers were susceptible to influenza, approximately three million workers would be infected, for an attack rate of 47%.  Vaccination reduced the infections to an attack rate of 28%, but additional workers are expected to have infection-acquired immunity.  Increased compliance with infection control procedures will decrease the burden of occupationally-acquired infection.

Conclusions: The burden of occupationally-acquired infection is non-trivial.  The risk assessment approach allows the impact of different infection control procedures on occupationally-acquired infection to be quantified.