Emergence of porcine epidemic diarrhoea in North America

overview Porcine epidemic diarrhoea virus (PEDv) was first recognized in the United Kingdom of Great Britain and Northern Ireland in 1971. Since then, PEDv has become endemic in many European and Asian countries, where PEDv infection typically results in minor outbreak incidents with relatively low mortality (Pan et al., 2012; Li et al., 2012b). In 2010, despite vaccination programmes, a virulent strain of PEDv caused high mortality in neonatal piglets in Chinese herds, and economic losses continue to mount (Geiger and Connor, 2013). The first outbreak of virulent PEDv in North American swine herds occurred in the United States of America in May 2013 (Ackerman, 2013). During the first months of the epidemic, PEDv losses contributed to a decline in the national market of between 2.5 and 4.2 percent (Meyer, 2013). The full economic impacts of PEDv losses in United States and Chinese pork markets have not been measured, and current efforts to prevent further losses focus on prevention and control strategies. ˜ Background information Global trade of live pigs, pig embryos, semen, feed ingredients and feed is relatively common, leading to a threat of transboundary PEDv transmission into the swine populations of naïve countries. It is worth noting that PEDv does not pose a public health risk as it does not cause disease in humans. However, PEDv can affect the livelihoods of producers in affected regions because of the severe and far-reaching economic losses that the disease imposes. These losses are particularly critical for small-scale farms where a high mortality rate can be devastating to food security, especially in developing countries. Coronaviruses are found worldwide and PEDv has been reported in 11 of the top 20 swine producing countries. PEDv is prevalent in some European swine herds, although current prevalence levels are unknown and it is believed that the disease does not cause major economic losses in Europe (Pan et al., 2012; Song and Park, 2012). PEDv has been a cause of enteric