Pig Fears as Bird Flu Death Toll Hits 18
February 6, 2004
By Christina Toh-Pantin
HANOI (Reuters) - Two more people have died in Vietnam of bird flu, taking Asia's death toll to 18, as a U.N. agency says tests revealed the virus in pigs, a potentially disturbing development that highlights the risks to humans.
A day after China said bird flu had spread to more provinces and U.N. agencies chided Asian countries for being slow to sound the alarm, the Food and Agriculture Organisation said on Friday three or four pigs had tested positive in Vietnam.
"The H5N1 virus was in the nasal cavities of the pigs," FAO Vietnam representative Anton Rychener said, adding that blood samples had been sent to Hong Kong for further tests. A Vietnamese official was unaware of any such finding.
Health experts had feared the virus -- ravaging poultry flocks in eight countries with two more reporting milder strains -- would get into pigs, whose immune system is similar to humans' and which suffer from a wide variety of diseases that also infect people.
Scientists say this makes them ideal vessels for mixing genes from the bird flu pathogen and the human influenza virus.
The World Health Organisation has said this could result in the emergence of a new subtype of virus for which humans would have no immunity.
"If there was a very widespread infection in pigs, then that would be a great concern that a pandemic strain might develop from it," Jacqueline Katz, a flu expert at the U.S. Centres for Disease Control and Prevention, said last week.
NARROWING THE ODDS
Experts say the possibility of a new strain sweeping through a human population with no immunity to it is remote, but that each outbreak narrows the odds a little.
That is one reason why the FAO and the World Health Organisation have been urging affected countries to act swiftly to stamp out the H5N1 virus, preferably by slaughtering poultry within three km (two miles) of an outbreak.
Transmission to hogs is a constant worry, especially in countries like Vietnam and China where poultry, pigs and people often live in close proximity.
South Korea said it was even considering evacuating people from bird flu zones to try to contain the virus.
China, home to the world's biggest poultry population and where the virus may have spread to 13 of 31 provinces, says it faces a tough fight to defeat the disease.
One of those provinces is Guangdong, where the Severe Acute Respiratory Syndrome, another virus that crossed the species barrier from animals to humans, originated before spreading to 30 countries and killing nearly 800 people last year.
China, widely criticised for covering up the SARS epidemic for several months, has promised openness in its battle against the H5N1 virus, but says parts of its animal disease prevention system are "weak and vulnerable".
Local officials have been ordered to report any suspected human case immediately. None has been found so far.
PRECAUTIONS
Vietnam's death toll rose to 13 after a six-year-old girl and a 24-year-old man died from bird flu in Ho Chi Minh City. Five people have also died of the disease in Thailand, taking the Asian human toll to 18.
Rychener said there was no cause for alarm or for the banning of pig trading. The nasal swab result "does not mean that the virus is in the bloodstream of pigs".
The pigs were likely to have been infected from digging their noses in dirt that was infected with the virus, he said and suggested farmers separate pigs from chickens to prevent infections.
World health bodies meeting in Rome said in a joint statement on Thursday the chance the virus could spread to other countries, "including those in distant regions, is likely to remain high" unless the right methods were used to stamp it out.
The virus is thought to be spread by migratory birds.
Avian influenza was not under control, said the FAO, WHO and the world animal health body, OIE, which also criticised "a lack of timely reporting" of the spread of infection.
Fifty million birds had been culled in Asia so far and poultry restocking alone would cost some $150 million (82 million pounds), said Louise Fresco, assistant director-general of the FAO.
Thailand, the world's fourth biggest chicken exporter which has slaughtered 26 million poultry, is confident it is wiping out the virus.
Deputy Prime Minister Somkid Jatusripitak said Thailand had only one "red zone" left -- the five-km (three-mile) area around a confirmed outbreak within which the government orders the slaughter of all poultry.
Last week, it had more than 140 in 29 of its 76 provinces.
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