Current Status of Porcine Epidemic Diarrhoea (PED) in European Pigs

Antas, Marta; Wozniakowski, Grzegorz

Oral ingestion causes viral replication in the epithelial cells of the small intestinal villi and to a lesser extent in the colonic villi, which results in degeneration of enterocytes and shortening of the villi (6, 24) . PEDV can infect pigs of all ages, causing watery diarrhoea and vomiting with anorexia and dehydration, which is the major cause of death in young piglets. The clinical signs depend on the age of the pigs, immune status of the herds, and virulence of the strain (1, 4, 20) . Lesions are observed in the gastrointestinal tract and are characterised by a distended stomach filled with completely undigested milk dots and thin, transparent intestine walls (34) . PEDV infection is clinically indistinguishable from other forms of porcine gastroenteritis diseases such as those caused by TGEV and PDCoV, therefore PEDV diagnosis cannot be made only on the basis of clinical signs and has to be confirmed by laboratory tests to make diagnosis final (7, 24) . A variety of PEDV detection methods are applied which include immunofluorescence (IF) or immunohistochemistry (IHC) tests, in situ hybridisation, virus isolation, enzyme-linked immunosorbent assays (ELISA), and various reverse transcription polymerase chain reaction (RT-PCR) techniques. Samples which can be used in laboratory diagnosis are fresh faeces, oral fluids, small intestine tissue, and serum (to determinate the presence of antibodies). To detect PEDV RNA, RT-PCR can be used for diagnosis of acute outbreaks no longer than 14 days after the onset of the disease. For surveillance and monitoring of PED, serological diagnosis is necessary. Antibodies persist for more than one year in the serum of infected pigs (1, 13, 24) .