Simple on-farm ASF test kit passes clinical trials, is ready for commercial production, researchers say
Pig farmers may soon be able to screen for African swine fever (ASF) from the comfort of their own barns as on-farm test kits for the disease come closer to fruition.
A test kit developed by Silver Lake Research and Kansas State University recently demonstrated efficacy in detecting ASF in the blood of pigs in a laboratory setting, yielding 95% efficacy and just one false positive, according to Jürgen Richt, the regents distinguished professor of diagnostic medicine pathobiology at Kansas State University. The kits are being field tested in Vietnam and Cambodia, Richt said.
Richt, whose area of research is vaccines, diagnostics and feed safety, particularly with respect to ASF, had already developed the antibodies necessary to detect ASF. Six months ago, he said, Kansas State University granted a license to Silver Lake Research to incorporate the antibodies into on-farm test kits, which Silver Lake Research is now producing.
The kit is fairly simple to use, Richt said. A tube is filled with a mixture of water and a drop of blood drawn from a potentially infected pig. A test strip is then inserted into the mixture for 20 minutes to determine if the virus is present.
The test is not as effective as laboratory screening, Richt said, but is much faster. While it can take a day or more to get laboratory results, the test kit will enable producers to screen their herd for ASF in a matter of minutes. The kit is most effective in pigs already showing moderate to severe symptoms of ASF; efficacy declines if the animals have only recently contracted the virus.
“The more severe the case, the more positive the test is,” Richt said.
On-farm testing was one of several technologies identified late last year by the National Pork Board as being critical to controlling the spread of ASF. When the virus is introduced to a new area, quarantine could prevent ASF from spreading, but only if the virus is detected before the pigs are dispersed, Richt said.
“These diseases, if you don’t stop them as soon as you can, spread very easily,” he said. “It’s a doomsday scenario almost.”
Richt said he believes the tests are ready for commercial use, although he said it is also important to understand how the kits perform in the field in infected countries. Silver Lake Research has shipped some 500 test kits to Vietnam and Cambodia for testing; however, the outbreak of coronavirus seems to have delayed the field tests, according to a company spokesperson.
View our continuing coverage of the African swine fever outbreak.