Germany's GM concerns

levels of illness but low death rates in pigs. These viruses may circulate among pigs throughout the year, but most outbreaks occur during the autumn and winter months, similar to flu outbreaks in humans. The classical swine flu virus (an H1N1 virus) was first isolated from a pig in 1930. Like all influenza viruses, swine flu viruses change constantly. Pigs can be infected by avian influenza and human influenza viruses. When influenza viruses from different species infect pigs, the viruses can reassort and swap genes and new strains that are a mix of human, swine and avian influenza can emerge. It's this potential mix that alarms public health bodies. Over the years, different variations of swine flu have emerged — there are now four main type A subtypes that have been found in pigs: H1N1, H1N2, H3N2 and H3N1. But the most recent outbreak linked to Mexico has been H1N1. Swine flu viruses do not normally infect humans; however, sporadic infections with swine flu have occurred. Most commonly, these occur in people with direct exposure to pigs. In addition, there have been documented cases of one person spreading swine flu to other people before the present outbreak. An outbreak of apparent swine flu in Wisconsin in 1988 resulted in multiple human infections and, although no community outbreak resulted, there was antibody evidence of viral transmission from patients to health-care workers that had been in contact with the patients. Studies have shown that the swine flu H1N1 is common throughout pig populations worldwide, with 25 per cent of animals showing antibody evidence of infection Previously, in 1976, there was an outbreak of swine flu amongst soldiers at Fort Dix, New Jersey. The virus caused disease, with x-ray evidence of pneumonia in at least four soldiers, and one death — all of these soldiers had previously been healthy. The virus was transmitted to close contacts during basic training, with limited transmission outside the training group. The virus is thought to have circulated for about a month and then disappeared. The source of the virus, the time of introduction into Fort Dix, and factors limiting its spread are unknown. H1N1 and H3N2 swine flu viruses are endemic among pig populations in the US and something that the industry deals with routinely. Studies have shown that the swine flu H1N1 is common throughout pig populations worldwide, with 25 per cent of animals showing antibody …