South Dakota’s animal disease lab is on the lookout for African swine fever – the disease that’s devastated China’s pork industry over the last year and spreading throughout Asia.
The newly upgraded South Dakota Animal Disease Research and Diagnostic Laboratory on the South Dakota State University Campus in Brookings is one of 10 across the U.S. that’s part of an active surveillance effort for African swine fever.
When a sick pig shows warning signs like fever, anorexia, abortion, lameness and hemorrhaging, tissue samples are taken from the spleen, tonsil or lymph node and tested for both African swine fever and classical swine fever.
The U.S. Department of Agriculture pays for the test at no cost to the producer or veterinarian.
The surveillance program started June 1. It’s one of several ways government programs are keeping a lookout for African swine fever. Other programs to protect U.S. pigs from this foreign animal disease are to have beagles at international airports sniffing out food from high-risk countries.
“There are many groups doing a lot of work to make sure we don’t get African swine fever in the U.S.,” said Dr. Jane Christopher-Hennings, director of the state’s Animal Disease Research and Diagnostic Lab.
Along with active surveillance for the disease, the South Dakota lab has been involved in research efforts relating to African swine fever. The lab was part of a USDA “negative cohort” study looking for a way to test groups of pigs for the disease all at once using saliva tests. Such samples work for other swine diseases such as porcine reproductive and respiratory syndrome (PRRS), but it’s never been validated for the African swine fever virus.
The study didn’t turn up any false positives. Now researchers are doing a positive cohort study working with pigs that have African swine fever in other countries to be sure it detects the disease.
The lab has also worked with Pipestone Veterinary Systems on feed studies since there’s a risk that viruses can spread through contaminated feed. The studies have looked into how long viruses can survive in feed and have evaluated recommended holding times to decrease the risk of spreading the virus.
The newly finished upgrade at the lab in Brookings provides extra security when handling highly contagious viruses like African swine fever. However, in the case of African swine fever, the virus does not infect people and it is not a food safety risk.
The lab now has a Biosafety Level 3 (BSL-3) section – the second from the highest biosecurity level. The HVAC system in that area is designed with negative air flow so viruses wouldn’t be able to travel to other parts of the building or into the air outside the building. Work there is also done under special hoods for laboratory personnel safety and biosecurity. The BSL-3 laboratory serves as a type of “quarantine room” such as what you might have in a human hospital to keep any pathogens in a specific, defined area.
The lab played a big role in keeping up with tests for avian influenza during the 2015 outbreak and the porcine epidemic diarrhea virus (PEDv) outbreak in 2013.
“We are prepared to do any testing at any time, but having the new laboratory addition makes our work easier and safer,” Christopher-Hennings said.