Swine origin influenza virus (SoIV) vaccines are extensively used in the swine industry in Europe and North America. Most swine flu vaccine manufacturers include an H1N1 and an H3N2 SoIV strains.
Swine influenza has become a greater problem in recent decades. Evolution of the virus has resulted in inconsistent responses to traditional vaccines. Standard commercial swine origin flu vaccines are effective in controlling the problem when the virus strains match enough to have significant cross-protection and custom (autogenous) vaccines made from the specific viruses isolated are created and used in the more difficult cases. SoIV vaccine manufacture Novartis paints this picture: "A strain of swine origin influenza virus (SoIV) called H3N2, first identified in the US in 1998, has brought exasperating production losses to swine producers. Abortion storms are a common sign. Sows go off feed for two or three days and run a fever up to 106°F. Mortality in a naïve herd can run as high as 15%."