Infection risks from electrically operated breast pumps.

Area of Science:

• Microbiology
• Biomedical Engineering
• Public Health

Background:

• Electric breast pumps are widely used for infant feeding.
• Concerns exist regarding the potential for bacterial contamination during milk expression.
• Staphylococcus epidermidis is a common bacterium that can cause opportunistic infections.

Purpose of the Study:

• To investigate the potential for bacterial contamination and aerosolization using electric breast pumps.
• To identify the routes of contamination within the breast pump apparatus.
• To assess the effectiveness of standard cleaning procedures in preventing contamination.

Main Methods:

• Formula milk was seeded with Staphylococcus epidermidis as an indicator organism.
• Three electrically operated breast pumps were used in repeated trials.
• Bacterial presence was assessed at various sites within and beyond the pump apparatus, including collected milk and exhaust air.

Main Results:

• Bacteria were detected beyond the collecting bottles, indicating passage through the pump system.
• Contamination levels increased with repeated use of the breast pump.
• Retrograde contamination of freshly collected milk was observed even with sterile collection bottles.
• Bacteria were recovered from sites distal to visible contamination.

Conclusions:

• Electric breast pumps can aerosolize and disseminate bacteria, posing a risk of contamination.
• Standard sterilization protocols may be insufficient to prevent contamination with repeated use.
• Terminal in-line air filters are essential to prevent contamination of the suction source and environmental emission of bacteria.
• Adequate sterilization of all removable components is critical when a single pump is shared.