BANGKOK, Feb 23 (Reuters) Vaccination and well-organised grass root monitoring networks are the reasons for bird flu's unexpected failure to spread during Thailand and Vietnam's recent ''cold season'', officials said today.
Even as the deadly H5N1 virus has winged its way across Asia to Europe and Africa, researchers are taking some heart that it has remained relatively dormant in a region which many thought would be the epicentre of a possible human pandemic.
In previous years, the virus had appeared to thrive in the November to February ''cold season'' in Vietnam, where 42 people have died of bird flu, and nearby Thailand, where 14 have died.
However, Vietnam has found no outbreaks in poultry or humans since November and Thailand has gone 106 days without any fresh reported cases in birds. Its last human victim was in early December. Cambodia has also avoided any new cases.
''Vietnam worked on vaccinations ahead of the start of the cold season,'' said Wantanee Kalpravidh, who coordinates a monitoring network in southeast Asia for the Food and Agriculture Organisation.
''We believe that reduced the risk and the circulation of the virus,'' she said after a mass campaign to inoculate fowl.
World Health Organisation officials in Vietnam concurred, saying Hanoi's speed in setting up mass vaccination and culling programmes, as well as raising public awareness through state-controlled media, had been key to the fight.
''The government has worked hard to strengthen preparedness and prevention efforts and good progress has been made,'' said Dida Connor, a WHO spokeswoman in Hanoi.
In addition, she noted that authorities in Hanoi and Ho Chi Minh City had staged mock bird flu emergencies to test the effectiveness of their response as well as banning production of duck eggs and closing live poultry markets late last year.
''The combined effect of vaccination and production and market intervention has almost certainly helped contribute to the improved disease situation,'' she said.
In Thailand, where state control is far less than communist Vietnam, the government chose not to vaccinate, but managed to halt H5N1 with a national army of almost one million volunteers, Wantanee said.
''When they have sporadic outbreaks, they pick them up right away and can get rid of them,'' she said.
Despite this, both the WHO and FAO say there is little room for complacency in a region where backyard poultry farming remains the norm, and where scientists say the virus has become endemic after first striking in late 2003.
''We are dealing with a virus that is not only resilient but also extremely unstable and unpredictable,'' Connor said.
REUTERS SHR DS1620