The Porcine Epidemic Diarrhea virus (PEDv) first struck the US coasts in April 2013, leaving public health and veterinary doctors puzzled because they could not figure out how it arrived across the ocean despite stringent measures on animal import. This virus has now made its way across to Oahu, the most populous island of Hawaii. The real question remains the same: how did it get there? Hawaii had adopted a stringent policy on importation of animals and testing of animals before they were brought in. Still, the virus, which has killed almost 10% of the US porcine population (almost 8 million pigs), and has been reported to have a case fatality rate upwards of 25%, has made its way across the ocean!
The thing with islands is that the diseases that are seen on the mainland of a continent need a vehicle for passage. Identifying that vehicle is now out of the case as it would now be too late and what with the entire focus on damage control and limiting the outbreak, there would be little else to go on. Besides, the sheer number of variables that could be potential vehicles for the virus would be mind-numbing, let alone following them up to trace back the route of the spread of the virus.
Though I am personally not very interested in porcine diseases, the Swine Flu has shown the world what powers pigs have when it comes to generating species-jumping, country-coursing viruses that set public health systems aflutter on a global scale. Although it seems unlikely that there will be a species jump for the diarrhea virus, the very fact that it made its way across vast expanses of oceans, despite intense scrutiny, and that too not just once, but twice, is something that does not sit too comfortably with me. In any case, it seems likely that the epidemiological riddle of how the diarrhea virus got into the US mainland and then onto Oahu will remain unsolved: and one can only hope that the virus does not make the species jump again.