[Immune response of body after Mycobacterium avium subsp. paratuberculosis infection and advances in detection methods - A review].

The progressive form of clinical Mycobacterium avium subsp. paratuberculosis (MAP) is characterized by production losses, weight loss, chronic intractable diarrhea, and severe emaciation leading to death in cattle. Substantial economic losses to the animal husbandry are a result of infection. Cattles are usually infected in their youth through the oral route and will experience a long subclinical stage. At the early stage of infection, cellular immunity is the main immune response with bacterium excretion increased significantly after a subclinical period of 2 to 5 years. The majority of methods currently used to detect MAP are based on etiological detection, cellular and humoral immune response. Owing to the different mechanism of diagnostic methods varies a lot at a particular infection period. In this review, we illustrate the transmission route and the characteristic of immune responses of MAP, and also summarize the diagnostic methods of MAP.