Incidence of paratuberculosis pathogens in Swiss raw milk

Mycobacterium avium subsp. paratuberculosis (MAP), cause of paratuberculosis in cattle and other animals, is meant to be suspicious for being involved in Crohn’s disease, an inflammatory bowel disease of humans. As the bacterium is able to partially survive the pasteurization of milk and the process of cheese ripening, it is important to know the presence of living MAP in Swiss raw milk. In the current study, 232 bulk milk samples from different parts of Switzerland were analysed for the presence of living MAP by cultural method. As MAP was not able to be detected in any sample, one can conclude, that Swiss raw milk is not massively and widespread contaminated with MAP. However, a final risk assessment can only be performed, if studies are present using a reference method for MAP detection which is still needed to be developed.