Aerosolized vaccine as an unexpected source of false-positive Bordetella pertussis PCR results

Area of Science:

• Microbiology
• Vaccinology
• Molecular Diagnostics

Background:

• Pertussis (whooping cough) is a significant public health concern.
• Accurate diagnostic methods are crucial for disease surveillance and control.
• Potential sources of prelaboratory contamination in molecular testing require careful consideration.

Purpose of the Study:

• To investigate the cause of unexpected positive Bordetella pertussis PCR results in nasal wash specimens.
• To identify potential sources of prelaboratory contamination in a clinical setting.

Main Methods:

• Analysis of 13 nasal wash specimens from a single pediatrician's office.
• Investigation into potential contamination sources, including vaccine lots.
• Polymerase Chain Reaction (PCR) testing for Bordetella pertussis DNA.

Main Results:

• All 13 nasal wash specimens tested positive for low quantities of Bordetella pertussis DNA.
• Investigation identified Pentacel and Adacel vaccines as containing high copy numbers of B. pertussis DNA.
• Aerosolization of vaccine DNA was identified as the likely cause of false-positive PCR results.

Conclusions:

• Vaccine components can be a source of prelaboratory contamination in Bordetella pertussis PCR testing.
• Aerosolized DNA from certain vaccines can lead to false-positive diagnostic results.
• Careful handling and environmental controls are necessary to prevent vaccine-related contamination in molecular diagnostics.