Same-Day Quantitative Detection of Campylobacter from Boot Swab Rinsates

Introduction: Boot swab sampling is a simple, cost-effective method for assessing microorganism burdens in poultry flocks prior to processing. Current rapid detection methods fail to deliver accurate, quantitative results for boot swab rinsates. Here we highlight a novel DNA-signature capture platform capable of providing same-day detection of Campylobacter from boot swab rinsates.

Purpose:   The study evaluated the Veriflow Campylobacter Q assay as a tool for rapid, quantitative detection of Campylobacter species from boot swabs. The assay produces quantitative results in under 3 hours without sample enrichment.

Methods: 142 boot swab samples were collected from 48 locations during Fall 2016, including turkey and chicken grow houses, hatcheries and breeders. Samples were stored at 4^oC until analysis. Samples were rinsed in 400 mL Buffered Peptone water, concentrated by centrifugation and recovered in assay buffer designed for poultry samples. Samples were then amplified by PCR, detected via handheld cassette, and quantified via optical reader.

Results:  A positive detection threshold for the assay was set at > 300 cells/mL of rinsate. 24.6% of all samples tested were positive for Campylobacter. Among grow house samples, 35.6% of all turkey samples were positive (16/45) and 33.3% of chicken samples were positive (19/57). Quantitative results of positive samples show an average range of log₁₀ 2.6-3.9 cells per mL of rinsate by location, identifying relative risk of downstream contamination in these flocks. 

Significance: Measuring Campylobacter levels from boot swab rinsates can provide valuable, real-time data regarding the microbial contamination of flocks prior to being processed. This will allow for a detailed analysis of flocks prior to live-haul, enabling staging of high and low burden flocks to manage risk during production.