Bacillus species pseudo-outbreak: construction works and collateral damage

Area of Science:

• Infectious Diseases
• Hospital Epidemiology
• Environmental Microbiology

Background:

• Hospital construction projects can pose risks for healthcare-associated infections.
• Bacillus species bacteraemia can be challenging to distinguish from contamination.
• Emergency departments (EDs) are high-traffic areas with vulnerable patient populations.

Purpose of the Study:

• To investigate a pseudo-outbreak of Bacillus spp. bacteraemia in an ED.
• To identify the source and contributing factors of the pseudo-outbreak.
• To implement and evaluate infection control measures.

Main Methods:

• Retrospective analysis of blood culture data during a construction period.
• Environmental sampling of surfaces, materials, and air within the ED.
• Implementation of enhanced infection control protocols.

Main Results:

• A significant increase in Bacillus spp. bacteraemia (1.7%) during the pseudo-outbreak period compared to baseline (0.31%).
• Environmental samples confirmed Bacillus spp. contamination on surfaces, materials, and in the air.
• Bacteraemia cases rapidly decreased after implementing infection control measures and completing construction.

Conclusions:

• Construction activities in the ED were the likely source of environmental contamination leading to the Bacillus spp. pseudo-outbreak.
• Inadequate barrier precautions during hospital construction can increase patient and healthcare provider risk.
• Effective infection control strategies are crucial to prevent pseudo-outbreaks during healthcare facility renovations.