Prevalence of Campylobacter species and associated risk factors for contamination of dairy products collected in a dry season from major milk sheds in Ethiopia

Abstract

A cross-sectional study was conducted to investigate the prevalence and risk factors for contamination of Ethiopian dairy products with Campylobacter. A total of 912 dairy food samples were collected from establishments of 682 study participants that were interviewed. Samples were tested for Campylobacter by following the ISO 10272-1:2017 standard and PCR confirmation. Campylobacter was detected in 11% of tested food samples and all detected Campylobacter were C. jejuni. The highest prevalence of C. jejuni was found in raw milk (16%), followed by pasteurized milk (9%) and cottage cheese (2%) (P < 0.001). Using warm water and soap for cleaning cow udders and teats on farms reduced the likelihood of detecting Campylobacter in milk (AOR = 0.3, P = 0.023). Filtering milk with a cloth, using a plastic filter (AOR = 0.065, P = 0.005), and storing milk in an aluminum container (AOR = 0.23, P = 0.027) reduced the likelihood of detecting Campylobacter in milk at the collection facilities. In contrast, Campylobacter detection was significantly more likely in milk collected at collection centers with concrete floors (AOR = 5.2, P = 0.004). The odds of detecting Campylobacter in milk were 17 times greater (AOR = 17, P = 0.007) in milk processing facilities that did not calibrate a pasteurizer on an annual basis. Finally, having a separate refrigerator for milk storage reduced the odds of detecting Campylobacter in retail (AOR = 0.29, P = 0.021).

Keywords: Campylobacter jejuni; Contamination; Cottage cheese; Dairy products; Ethiopia; Pasteurized milk; Raw milk; Risk factors.