Studies conducted at the Virginia-Maryland Regional College of Veterinarian Medicine, involving sequence and phylogenetic analysis confirmed that three isolates obtained from cases in the U.S. have 99.5% homology to a virus responsible for PEDv in Anhui Province in China in 2010. Reporting on their findings in the American Academy of Microbiology, mBio Online, the research team did not speculate on the exact source and origin of the virus.
What is important is that an infectious agent responsible for extensive loses in China has emerged in the U.S. with significant consequences. This clearly indicates a break in our National biosecurity and questions the effectiveness of current procedures relating to issuing import permits, interstate movement of animal products and border surveillance. Although any comments on possible routes of introduction would be speculation and possibly “diplomatically incorrect”, it is strongly suspected that animal products are clandestinely imported from China to satisfy demand by specific ethnic demographics in North America.
Fortunately the research teams working with the virus have developed an indirect fluorescent antibody assay which can detect the presence of antibodies in recovered herds. This test could be of value in preventing lateral transmission of virus although it is not known whether a carrier state exists. It is however known that the virus is transmitted in hog waste and accordingly care should be exercised in disposal of manure.
The rapid dissemination of virus among numerous states around the U.S. within a year suggests both the infectivity of the virus and resistance to environmental effects. The fact that the infection has emerged in a number of states also indicates profound deficiencies in biosecurity.
The final story on PEDv has not been written. We should take note of the results of epidemiologic studies in progress and apply to our industry whatever lessons emerge. In this instance, the U.S. livestock industry is dealing with a swine disease. Tomorrow it could easily be an infection impacting poultry.