Special Topic
Avian Influenza
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Special Report Part 1: Vietnam's success against avian flu may offer blueprint for others The shift is so striking that international health authorities are asking whether Viet Nam's success can be replicated elsewhere. But reproducing its efforts faces an unusual hurdle: sorting out which of its aggressive interventions actually made a difference. "The absence of human cases is a direct reflection of the lack of cases on the animal side," said Dr. Richard Brown, a World Health Organization epidemiologist based in Hanoi. "But it is actually difficult to know exactly what that is due to, because there were a number of different interventions applied in the latter half of 2005 on the animal health side." After responding to its 2004 outbreaks mainly by culling infected flocks, Viet Nam in 2005 became the first country to institute mandatory nationwide poultry vaccination. In addition -- and almost simultaneously -- the national government banned poultry rearing and live-market sales in urban areas; restricted commercial raising of ducks and quail, which can harbor the virus asymptomatically; imposed strict controls on poultry transport within Viet Nam and agreed to examine illegal cross-border trade; and launched an aggressive public education campaign that deployed radio and TV advertising, neighborhood loudspeaker announcements, and outreach by powerful internal groups such as the Women's Union and the Farmers' Union. The country also compensated farmers for birds that had to be killed -- initially at 10 percent of the birds' market value, and now at 75 percent. "Who knows what impact any of these interventions had? This is a natural experiment" that lacks controls that could measure impact, said Dr. David Dennis, the Hanoi-based Viet Nam influenza Coordinator for the US Centers for Disease Control and Prevention. "How much [of the reduction in cases] is due to the natural history of this organism in birds? We don't know." Outside the country, experts presume the engine of flu control to be the pervasive influence of Vietnamese-style socialism, which extends from the national government through provinces, districts, and communes to individual "neighborhood committees." Dr. David Nabarro, the United Nations' senior coordinator for avian influenza, implicitly endorsed that view in a 19 Sep 2006 Financial Times story, when he contrasted Viet Nam's continued control of the virus with Thailand's recent [upsurge] in human cases during a time of political turmoil. "You don't maintain control over this disease unless there is regular top-level direction from a senior committed political figure that wants to be sure the necessary activities are being undertaken," Nabarro told the Financial Times. But within Viet Nam, workers in avian-flu control say the country's success depends as much on the population's support as it does on political coercion -- a factor that may bode well for the national government's plans to change the country's entire culture of poultry rearing, distribution, purchase, and sale. (See Part 2 for more "Some farmers may not understand that they cannot eat duck blood, because they see that the duck looks healthy," said Nguyen Van Mai, a trainer with the humanitarian organization CARE International, an Abt Associates partner. "Some think that [avian flu] has stopped already, and do not believe that it is coming back." The farmers' confidence is not shared by health authorities apprehensive over the approach of winter -- Viet Nam's regular flu season, and also the time of year when avian flu cases have [peaked]. "I think Vietnam . . . has to prepare to deal with the [return] of this epidemic," said Dr. Le Truong Giang, Vice-director of the Health Department in Ho Chi Minh City, which is Viet Nam's largest municipality and has enacted the strictest local flu controls. Asked whether the city could keep the virus at bay indefinitely, Dr. Giang paused. "We try to do that," he said. "But we are not sure." [Byline: Maryn McKenna] ****** When avian flu control meets cultural resistance The willingness of Tich and thousands of small farmers like him to follow the government's orders does much to explain Viet Nam's dramatic change of fortune on avian flu, from one of the countries hardest hit by the virus to one of the most successful in controlling it. The Vietnamese government is openly proud of those results, and international animal and human health experts have applauded its apparent success. Yet some of those experts caution, and interviews with farmers and consumers confirm, that Viet Nam's continued success is not guaranteed -- because it may depend on new and stricter government prescriptions that the populace may find hard to accept. "What is being talked about is trying to change really basic behavior that people have been engaged in all their lives," said Dr. Richard Brown, a World Health Organization (WHO) epidemiologist based in Hanoi. "It is going to be a slow process." As the H5N1 outbreak expands, planners worldwide are acknowledging that scientific and political efforts to control the virus will fail unless they are accompanied by willing cultural change. Viet Nam's attempts to create that change are being closely watched. Viet Nam's success against avian flu has made the country an island of viral suppression in a sea of transmission -- this year, according to reports from the World Organization for Animal Health (OIE), H5N1 has recurred in neighboring Cambodia, China, Laos, Myanmar, and Thailand. And Viet Nam's successful measures are stringent and strictly maintained. In Ho Chi Minh City, for instance, raising chickens in the city has been banned, and chickens raised in the countryside are inspected twice before they cross the city limits -- once by rural authorities and a 2nd time at one of 4 municipal checkpoints. More than 2000 trucks pass through the checkpoints each day; if the birds' paperwork is in order, the truck carrying them is allowed to proceed along limited designated routes to one of 3 new slaughterhouses. If the birds do not pass inspection, they are confiscated on the spot. "We take them to the incinerator," Dr. Truong Thi Kim Chau, vice-director of the city's sub-department of animal health, said through an interpreter. "The risk of bird flu still exists in Viet Nam," said Dr. Bui Quang Anh, the Hanoi-based director general of the department of animal health in the agriculture ministry, pointing to the likelihood that the virus still circulates in ducks, geese, and quail within Viet Nam, and the possibility of its being carried over the Chinese border in smuggled live chickens. To counter that perceived threat, the Ministry proposes strict additional prevention measures in its Integrated National Operational Program for Avian and Human Influenza, known because of its binding as the "Green Book." The measures vary. One proposal is to permanently ban the raising of ducks, an integral component of the rice-growing economy because they are herded into harvested paddies to clean and fertilize them. Another is to take poultry raising out of the hands of the backyard growers, who make up 70 percent of producers, and concentrate the industry in large, biosecure farms. Most controversially, for many Vietnamese, the government proposes to alter the way that chicken, a major food, changes hands. It is phasing out the markets where consumers choose live birds and have them slaughtered, and substituting birds killed in a modern slaughterhouse and sold shrink-wrapped and chilled in supermarkets. The change -- already instituted in Ho Chi Minh City and under way in the north -- would alter much more than basic commerce. It challenges deep-rooted food preferences, because already-dead chickens are considered less tasty and nutritious. It could affect social patterns, because markets are where neighbors meet each morning. It touches even religious practice: Slaughtering and cooking chicken on behalf of family ancestors is a crucial observance during Lunar New Year. "This is the big challenge in Vietnam," said Dr. Le Truong Giang, vice-director of Ho Chi Minh City's health department. "Not all the population agree, but more and more people agree with us." In Viet Nam's health agencies, and in the cities and villages, there are scattered signs that acceptance of anti-bird flu measures may not be complete. The 2-shot poultry vaccination campaign mandated [in 2005] by the agriculture ministry inoculated approximately 160 million birds -- 80 percent of the country's total (Herd Immunity?)-- in late 2005, Dr. Anh said. But a repeat this year, meant to catch a new crop of birds, vaccinated 140 million, about 65 percent. And a campaign to halve the country's duck population, which stood at 60 million in 2003, has stalled at 40 million birds. On a mid-September morning in Viet Doan commune -- where 1500 ducks were culled in 2005 -- 400 local farmers followed along eagerly as a team from CARE International staged games and contests with an anti-flu theme. The gathering was part of a program that the humanitarian agency has been testing in Viet Nam since 2004 that coaches rural residents to evaluate their own understanding of avian flu and teaches them preventive measures, from handwashing to keeping poultry away from other animals. "Some food shops in the commune have stopped selling poultry meat or duck's blood," said Dr. Nguyen Thi Tuyet Mai, a trainer on the program's staff. "Some farmers keep their poultry behind a fence. But it is difficult to change behavior; it requires a long time." Tich, the farmer, did not attend the gathering. At his farm down the road, there was a modest fence, 2 strands of barbed wire slung loosely between low posts. A chicken flapped over it, landing clumsily in a mob of month-old ducklings [photo at URL above] -- ducklings that, under a strict interpretation of government guidelines, should not exist. Asked about the ducks, Tich looked nonplussed. News of the ban, he said, had reached him only 10 days ago; he had bought the ducks 3 weeks before. "What I heard is, the local authority just encouraged not to raise new ducks." he said through the interpreter. "It is not a policy." Tich had complied with most of the policies in the government campaign against avian flu. In addition to vaccinating his adult birds and confining his chicks until they are a month old, he scours his chicken coops with disinfectant every time a crop is sold, wears gloves and a mask when he kills a bird for his own use, and buries dead chickens in a hole with lime instead of eating them or feeding them to fish. But he seemed skeptical of the effort and expense in some of the further measures yet to come. "Avian influenza is a very big concern for our family, because we have invested quite a lot of capital in our poultry," he said. "But if the government banned duck-raising, I might switch to raising other animals. I might not grow poultry anymore." [Byline: Maryn McKenna] |