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

Antas, Marta; Wozniakowski, Grzegorz

The first symptoms of the disease in the USA were observed in April 2013 and were confirmed in the laboratory in May 2013. The PED virus had escaped from biosecurity and control systems, spread very quickly to other areas, and infected hundreds of farms. By March 2015, the presence of PEDV had been confirmed in 31 US states. PEDV epidemics resulted in significant economic loss there, and the domestic pig industry lost almost 10% of its population (seven million pigs) (3, 12) . The PED outbreak was characterised by watery diarrhoea, dehydration, and variable vomiting. All groups of animals were affected by the epidemics, but the highest mortality was 95% and occurred among suckling piglets (10, 15) . The strains isolated in the USA were genetically related to the Chinese PEDV strains reported in 2012. PEDV was probably dispersed in the USA mainly through contaminated trucks, but other factors that assist the spread of the virus cannot be excluded (15) . Two strains of PEDV have been identified in the USA: highly virulent NON-INDEL (USA/Kansas29/2013) and the milder variant S-INDEL (USA/OH851/2014) (2) . Both variants were classified to genotype 2. In experimental infections, S-INDEL strains showed lower pathogenicity and mortality (from 0% to 70%) than the NON-INDEL strains, where the mortality rate was up to 100% (2, 30, 36) . Since the PED outbreak in the USA, detection of highly virulent strains has also been reported in Canada, Mexico, Taiwan, South Korea, Japan, and Ukraine. Detection of S-INDEL strains has been reported in most European countries (2, 12, 17) .