Influenza is a respiratory disease caused by type A influenza viruses that regularly cause outbreaks in pigs. To help detect this virus, the Ohio Department of Agriculture Animal Disease Diagnostic Laboratory offers same-day PCR test results for influenza A samples from swine.
Samples arriving in the laboratory by 11 a.m. will be reported by 5 p.m. Recommended samples are nasal swabs transported in BHI, viral transport media or sterile solution (3-5 cc). Samples should be shipped on ice overnight or delivered to the laboratory by courier. For more information, call ADDL at 614-728-6220.
Influenza is present at low levels in pigs throughout the world, and is monitored by the voluntary USDA Swine Influenza Surveillance Program, although it is not a reportable or regulated disease.
Like human influenza viruses, there are different subtypes and strains of influenza viruses in pigs. The main influenza viruses circulating in U.S. pigs in recent years are H1N1, H1N2 and H3N2. While H1N1 viruses have been known to circulate among pig populations since at least 1930, H3N2 and H1N2 influenza A viruses did not begin circulating among pigs in the United States until about 1998.
While influenza viruses almost always remain infectious only within their host species, at times infections may spread to other species. Influenza viruses in pigs can occasionally infect people, and human influenza viruses can infect swine. Health organizations use the term "variant" to refer to viruses that are genetically different from what is usually isolated from humans. The description is written as a small "v" after the virus subtype, for example, H3N2v. More information on these variant viruses is available from the U.S. Centers for Disease Control.