Raw Milk as a Source of Campylobacter Infection: Isolation and Molecular Identification of Campylobacter coli and Campylobacter jejuni in Ecuador

The consumption of raw milk has been demonstrated to carry a potential risk of transmission of <i>Campylobacter</i> spp., with <i>Campylobacter jejuni (C. jejuni)</i> and <i>Campylobacter coli (C. coli)</i> being the major causes for foodborne gastroenteritis cases. The present study assessed the prevalence and species distribution of <i>Campylobacter</i> spp. in 633 raw milk samples collected over a one-year climatic cycle from small, medium, and large producers in Pichincha and Manabí, Ecuador. Samples were augmented and analyzed by qPCR for <i>Campylobacter</i> spp., while species identification was performed by duplex PCR and confirmed by 16S rDNA sequencing. The average prevalence of <i>Campylobacter</i> spp. was 49.9% (316/633), with a higher detection rate in Manabí (57.6%, 182/316) compared to Pichincha (42.4%, 134/316). <i>C. coli</i> was the most prevalent species, accounting for 46.2% (146/316) of the cases, followed by <i>C. jejuni</i> at 23.1% (73/316), co-contaminations at 13.3% (42/316), and non-identified <i>Campylobacter</i> at 44.0% (139/316). Phylogenetic analysis was employed to confirm species identity, thereby confirming the presence of <i>Campylobacter fetus</i> and <i>Campylobacter lari</i>. The increased diversity and frequency of isolates in Manabí, particularly during periods of elevated temperature, imply that coastal environmental conditions and production practices promote the persistence of bacteria. The findings of this study indicate a high prevalence of <i>Campylobacter</i> in Ecuadorian raw milk, posing a significant health risk to the population and underscoring the need for enhanced hygiene practices and continuous monitoring to mitigate public health risks.