For Hoang Van Manh, a 36-year-old Vietnamese poultry farmer, it was an act of faith to keep feeding his 2,000 valuable chickens when bird flu swept across Vietnam in early 2004, claiming human lives and shutting down the once brisk poultry trade.
Manh, owner of three large egg incubators, had prospered by selling newly hatched chicks to other farmers, who then raised the birds. But as authorities banned the movement of all poultry in a belated effort to contain and eradicate the lethal H5N1 virus, demand for chicks plummeted, and the backyard hatchery operator was forced to kill 20,000 unwanted chicks and destroy 30,000 fertilised eggs.
Luckily, Manh's village, on Hanoi's outskirts, was more than five kilometres from any confirmed bird flu cases, so he was not required to cull the valuable adult birds, his breeding stock. Instead, he spent US$60 a day to keep them alive during anxious months without any sales.
"The government was calling for farmers to change to other jobs, instead of poultry raising, but I trusted that the authorities would be able to control this bird flu problem, and that we would be able to go on," he recalls.
Manh's faith was not misplaced. Vietnam - where bird flu once raged seemingly out of control in poultry, and where the virus killed 42 of the 93 people in the country known to have been infected - is an example of how determined, comprehensive efforts can check the potentially lethal virus.
The formula for battling bird flu in poultry - as it will be for controlling a human outbreak - is straightforward, involving early detection and containment of the virus to prevent its spread.
But David Nabarro, the United Nations coordinator for avian and human influenza, told IRIN that a country's success in implementing such measures depended primarily on the political will, and institutional ability, of a government to swing into action to confront the challenge - capabilities that Vietnam clearly mustered once it woke up to the threat.
"Governments that are relatively weak and disorganised are going to face a much tougher struggle when dealing with the threats of bird flu or a human pandemic, than governments that are more organised," Nabarro said. The weapons for successful control of bird flu, he said, "are the same factors necessary for a strong HIV/AIDS campaign, or a strong development programme".
The battle against bird flu begins with strong, high-level political leadership to galvanise the government machinery, and push it into action. "Officials in any government are always overloaded, and under-resourced, so for officials to move forward, they need to have the empowerment from political commitment," Nabarro said. "It provides the wind in the sails for the officials to do the work. It also requires bureaucracy to scale up a national level response, to co-operate across agencies that may not usually work closely together - such as departments of animal and human health - and ensure an adequate flow of information from local communities to central decision-makers, so they can map out the overall strategy in the face of rapidly changing conditions."
Governments must also engage the population by raising awareness of the risks of bird flu and the standard precautions against contracting and spreading the virus. Finally, governments must be willing to offer compensation to farmers for birds culled to give them an incentive to co-operate with the authorities, rather than to conceal birds that may be carrying the virus.
"You've got to have incentives for people to participate, which means some form of compensation for birds killed or property destroyed," Nabarro said. "It's vital to have strong public engagement, with good mass media."
Vietnam has certainly displayed what a poor country can accomplish, and is considered a model for other developing countries to emulate. After culling about 51m birds, or more than 17 percent of the domestic poultry population, and conducting a comprehensive vaccination campaign, Vietnam has not registered any human avian influenza cases since November 2005, nor any major outbreaks in birds since mid-December, despite a few minor flare-ups.
Vietnam's success is in stark contrast to countries such as Indonesia, where bird flu has killed at least 56 people since July 2005 and authorities are still struggling to contain a virus now thought to be highly pervasive in many parts of the country.
Still, agricultural analysts in Vietnam and Nabarro caution that the lethal H5N1 virus is almost certainly present in migratory birds, waterfowl and ducks, while domestic birds smuggled over the border from China could re-introduce the virus. Small disease outbreaks in domestic poultry could be passing unnoticed.
"It's like a ceasefire - some sort of temporary respite," said Jeffrey Gilbert, a Hanoi-based specialist on avian influenza from the UN Food and Agriculture Organisation. "But the virus is not gone, and we wouldn't be in the least bit surprised if there was a new outbreak."
Bird flu spread widely in Vietnam before authorities recognised the threat in early 2004 and moved into battle mode. While the government was not able to enforce fully its bans on poultry movements, duck-raising and live bird markets or its aggressive culling programme, its authoritarian communist structure proved useful for disease surveillance, raising public awareness and ensuring reasonable compliance with various restrictions.
When outbreaks persisted through mid-2005, the government raised the compensation for dead and culled birds to 50 percent of market value from 10 percent, encouraging more co-operation from farmers. Then last October, Vietnam launched an expensive, logistically complicated campaign to vaccinate domestic poultry. The measures appear to have checked the virus.
Vietnam's battle against bird flu is far from over. Bui Quang Anh, director of the Department of Animal Health, said recently that the government was worried about bird flu in China, and the uncontrolled cross-border poultry trade, while public complacency is another risk. "If people get tired and don't take precautionary measures, the situation will be very dangerous," he said. "If we don't pay attention, bird flu may re-erupt."
Indeed, for Manh, now back in business, the future looks bright. Sales are picking up as farmers rebuild their poultry flocks. His adult birds have been vaccinated, his monthly profits from bird sales are now about $625, and he is planning to expand his flock to 3,000 birds. "Things are getting better," he said. "Not many farmers are still worried about bird flu."