CampyTube: Seamless Integration of a Molecular Test and Lateral Flow Detection of Campylobacter in a Single Vial

The efficient control of hygiene and Campylobacter's contamination status at various steps of poultry meat production is essential for the prevention of Campylobacter transmission to humans. Microbiological methods are laborious and time-consuming, and molecular methods of detection are often too skill- and infrastructure-demanding.

We have developed CampyTube, a simple and user-friendly format for the integration of isothermal DNA amplification with embedded instrument-free detection on a miniaturized lateral flow test in a single vial. All test components, from the dry amplification reagents to the mini lateral flow tests, are incorporated into a standard single vial, which is closed after the addition of the liquid sample and never has to be opened again. This ensures the absolute prevention of carry-over contamination and makes the system very safe and simple to use in point-of-need settings.

As few as 60 Campylobacter genome copies per reaction could be successfully detected with CampyTube. We have primarily developed and evaluated CampyTube for the detection of Campylobacter in chicken neck skin samples and could reach 100% sensitivity and 100% specificity in the samples exceeding the regulatory limit of 1000 CFU/g confirmed microbiologically, while the sensitivity in all samples that tested positive using qPCR (1.4 × 10²-2.5 × 10⁶ genome copies/g) was 71.1%. We discuss the impact of sample preparation on CampyTube performance and suggest further options for test optimization.

CampyTube is a highly versatile and efficient, yet simple, affordable, and material-saving system that can be adapted for other targets and sample types.