Wild birds such as migratory ducks and geese have historically been known as reservoirs for avian influenza (AI) viruses. These birds normally can carry low pathogenicity avian influenza viruses in their respiratory or intestinal tracts and usually do not get sick. However, AI viruses, particularly H5 and H7 strains, can infect domestic poultry such as chickens and turkeys resulting in severe economic losses due to reduced production and increased mortality and culling. In 2014, USDA identified Eurasian H5N8 highly pathogenic avian influenza (HPAI) and mixed-origin viruses, H5N2 and a novel H5N1, in the Pacific Flyway. The HPAI H5N2 virus strain was later confirmed in several states along three of the four North American Flyways: Pacific, Central and Mississippi. This virus was associated with the HPAI outbreaks that started in the Pacific Northwest in December 2014 and spread to commercial chicken and turkey farms in the Midwest. The last case was reported in June 2015. However, by that time, the U.S. had endured the largest animal health emergency in its history, with more than 200 cases of HPAI affecting more than 50 million commercial and backyard poultry as well as wild birds across 15 states. On March 5, 2017, USDA confirmed HPAI H7 in a commercial poultry breeder flock along the Mississippi flyway in Tennessee. This HPAI H7 strain was found to be of wild bird lineage and was later confirmed by the USDA's National Veterinary Services Laboratories as a North American wild bird lineage H7N9 HPAI.
This community offers avian influenza-specific self-directed certification courses. The online courses are free, but you may need to enroll to gain access.