Nosocomial bacteremia. An epidemiologic overview

Area of Science:

• Infectious Diseases
• Hospital Epidemiology
• Public Health

Background:

• Nosocomial bacteremia affects 194,000 U.S. patients yearly, causing 75,000 deaths and significant healthcare costs.
• Most cases are endemic, secondary infections, but epidemics often stem from primary bacteremias, frequently linked to intravascular devices or infusion therapy.

Purpose of the Study:

• To analyze the characteristics and sources of endemic and epidemic nosocomial bacteremia.
• To identify risk factors and potential prevention strategies for these hospital-acquired infections.

Main Methods:

• Review of reported nosocomial bacteremia epidemics between 1965 and 1978.
• Analysis of causative agents, patient populations, and outbreak-related factors for both endemic and epidemic cases.

Main Results:

• Epidemics (78%) were more likely primary bacteremias than endemic cases, often linked to infusion therapy (33 outbreaks).
• Aerobic gram-negative bacilli caused two-thirds of endemic and 79% of epidemic bacteremias; certain species signaled epidemics.
• Epidemics predominantly affected immunocompetent patients and were associated with special care units (58%) or invasive procedures (65%).

Conclusions:

• Preventing endemic nosocomial bacteremia relies on consistent aseptic techniques (currently underutilized).
• Epidemic bacteremias offer greater prevention potential, particularly those linked to invasive devices or common contamination sources.