PEDv is still active in swine herds in the US. Unlike previous reports of TGE, which seemed to disappear after a national infection for several years, PEDv is still grumbling on so we need to take great care regarding importing breeding stock into the EU still.
Looking at the recent update for cases there has been an overall fall in the number of positive cases to October 2015 by about 44% from the previous year, which is great news.
Looking at the chart the winter months are the high risk months. There is limited warmth, dryness and sunlight to destroy the virus; it can survive for weeks in cold, moist conditions. In the northern states and Canada, where it freezes up in the winter, truck cleaning and disinfection becomes a major difficulty. Specialised truck cleaning and drying facilities have been installed to improve the situation but not only pig trucks are important potential carriers of the virus but feed delivery, dead pig removal and garbage trucks, which regularly visit farms, may also play a role in transmission.
General biosecurity appears to have improved, which is also still having a major effect on the incidence of breakdown with PRRSv. Cumulative breakdowns have come down from 35-40%/year to 20-25%, so some benefits have resulted from this horrible infection.
Due to the highly infectious nature of the PED virus and the comparatively poor immune protection post infection, the disease is still present and likely to increase in the coming months again, so we need to continue to be aware that it is still present.