Bird flu spreads to pigs
the deadly avian influenza strain H5N1 to pigs by stating that
recent tests carried out on pig farms in the country have shown
that the animals are now clear of the disease.
The report from the Chinese government comes just days after a Chinese health official disclosed the discovery that the strain had appeared in several pig farms located in parts of the country.
The World Health Organisation said it was waiting to get confirmation of the report and to clarify certain issues thrown up by both the discovery of the strain in pigs and how the outbreak has been allegedly bought under control. AP-FoodTechnology.com today spoke to Maria Cheng of the World Health Organisation's Communicable Disease Surveillance & Response division who said that, although it was still monitoring the threat posed to humans by the outbreak of disease in pigs, it did not have any evidence to prove that there was any significant threat at the present moment.
News of the outbreak in pigs came from China's Harbin Veterinary Research Institute. A spokeswoman for the institute reported at a press conference during an International Symposium on SARS and avian influenza held in Beijing last Friday. She said that this was the first known case of natural infection in pigs with this strain of the virus.
Health officials, including the World Health Organisation, have been alarmed by the outbreak. Although it is known that pigs can carry the disease, this outbreak indicates that the H5N1 strain is becoming increasingly virulent.
Further to this pigs are known as a link between spreading the disease to humans. This occurs because the animal is known to be a receptor to both the human form and the avian form of the disease, making them a 'mixing vessel' that can facilitate the exchange of genetic material between the two viruses. This means that the two viruses could interact to create an even more deadly strain of the disease - something that could prove particularly deadly to humans.
The World Health Organisation now says that its investigations are concentrating on how the disease is being spread to pigs. The supposition is that it is being caused by the animals coming into contact with wild birds. It has been proved that wild aquatic birds can carry the H5N1 strain without showing any symptoms. It is believed that the birds spread the disease through their excrement.
Meanwhile outbreaks of bird flu across Asia continue to cause nightmares for poultry farmers in the region, which has so far led to the culling of nearly 200 million birds. Last week Vietnamese authorities confirmed that three more human victims had succumbed to the disease, bringing the total number of deaths in both Vietnam and Thailand to 27. Further to this an outbreak of the disease in Malaysia has led Singaporean authorities to ban all poultry imports from its neighbouring country.
