Every day, despite an import ban, the smugglers were hauling more than a thousand contraband chickens into Lang Son, one of six Vietnamese provinces along the untamed Chinese frontier. In Lang Son alone, the jagged border runs for 150 miles through angular, misty mountains that seem drawn from a stylized Oriental painting. The highest peak, Mau Son, rises nearly 4,500 feet. It also lends its name to the local rice wine, widely sold in unmarked, five-hundred-milliliter plastic bottles for about sixty cents each. My government escorts had knocked back enough shots over lunch that it had taken some of the edge off their anxiety.
For centuries, extended tribal families straddling the border have navigated highland footpaths to run goods from one side to the other. In recent years these had come to include electronics, DVDs, exotic wildlife, and all sorts of clothes and shoes. The illicit poultry business had turned lucrative in 2004 after Vietnam began slaughtering about 50 million chickens to contain its bird flu epidemic. The resulting shortage of chicken meat, a favorite protein source for the Vietnamese, sent prices soaring on their side of the border. But with the increase in the illegal poultry trade, the traffickers had also unknowingly—and repeatedly—smuggled the virus from its source in southern China into Vietnam, at times introducing altered strains that bedeviled efforts to contain the outbreaks.
Two months before my visit to Lang Son in July 2006, Vietnamese veterinary officials had disclosed they’d identified the virus in a sample taken there from smuggled chickens during a bust on the border. Two years later, provincial health authorities reported they were discovering H5N1 in nearly a quarter of all the illegally trafficked chickens they were confiscating. Researchers had already uncovered lab evidence implicating cross-border commerce in spreading the disease. In mid-2005 they had isolated a strain of the H5N1 virus in Vietnam that was entirely new to the country—different from the subtype that had burned through farms starting in 2003 and killed dozens of people—but similar to one found months earlier in China’s Guangxi region, just over the mountains from Lang Son. Another study published in 2008 found genetic evidence that the virus may have been introduced from Guangxi to northern Vietnam on “multiple occasions,” most likely by poultry trade.
An average of 1,500 birds came over the mountains into Long San each day, provincial officials reported. Along the entire Vietnam-China border, the total could run well into the thousands. The syndicates running the smuggling rings were paying local villagers about thirty cents a bird to haul the contraband along mountain trails that could snake for more than ten miles. Some smugglers, especially women and children, could carry only a few birds. But hardy highland men lugged as many as twenty at a time. Their earnings could far outstrip the salaries of animal-health officers, inspectors, and others charged with stemming the commerce.
Once the smugglers came down from the slopes, they often transferred their haul to motorbikes, which ferried it to local farms serving as transit depots. From there, the chickens were loaded onto trucks for transport, in many cases to the markets of Hanoi, five hours away, and points even farther south. The smugglers were repeatedly seeding new outbreaks, and each outbreak was affording the virus a new chance to ensnare human victims and, even more ominously, mutate. This was how the novel strain continued to press its offensive.
Do Van Duoc was the director of animal health in Lang Son, a friendly man with full cheeks and silver hair that sat atop his head like a mushroom cap. He explained it would be nearly impossible to stem the smuggling as long as prices on either side of the border were so different. On average, chicken that sold for thirty cents a pound in China was fetching a dollar or more in his country. But that wasn’t the whole explanation. He accused Chinese farmers of unloading chickens from areas struck by bird flu at bargain-basement prices.
China’s agriculture ministry confirmed for me that poultry was being illegally transported into Vietnam. An investigation by Guangxi animal-health investigators had discovered three clandestine routes originating in different areas adjacent to Lang Son. But Chinese officials, true to form, denied that any birds coming from their side of the border were infected. Duoc wasn’t buying that. “We have evidence,” he told me. “We’ve tested and we can prove there’s H5N1.”
The farther influenza goes, the closer it comes to hitting the microbial jackpot. Extent means opportunity, more chances to mutate or swap genes. By 2009 the virus had stricken birds in at least sixty countries and spread to people in fifteen of them.
The strain made its debut in Europe in October 2004 when customs officers at Brussels airport discovered two infected eagles in a passenger’s hand luggage. A Thai traveler had smuggled them from Bangkok, wrapping the creatures in cotton cloth and shoving them headfirst into a pair of two-foot-long woven bamboo tubes. Then he had tucked these into an athletic bag, left unzipped slightly so the birds could breathe. His delivery had been destined for a Belgian falconer who had paid nearly $1,900 for the pair. They would have arrived unnoticed but for the passenger’s bad luck. He was stopped and searched as part of a random drug check. “We were very, very lucky,” Rene Snacken, the flu chief at Belgium’s Scientific Institute of Public Health, said at the time. “It could have been a bomb for Europe.”
But before long the virus indeed exploded out of East Asia. The startling outbreak among migratory birds at China’s Qinghai Lake in April 2005 had left Hong Kong’s Yi Guan and other scientists wondering where the virus might next wing. Over the following year, the disease struck birds in more than forty countries in Europe, Africa, South Asia, and the Middle East, and each time researchers checked, they found the distinctive genetic signature of the Qinghai subtype. By that winter, a dozen people had fallen sick in Turkey, four fatally, bringing human casualties to Europe’s doorstep for the first time. Wild birds and domestic poultry were succumbing in more than two dozen European countries. Panic spread. In Paris, the famed bird market on the Ile de la Cite removed all live fowl, and France’s annual livestock festival took the unprecedented step of banning poultry. In Britain, where legend claims that the monarchy will survive only as long as the ravens at the Tower of London, these celebrated birds were locked up for their own protection for the first time in history.
The virus struck in the Middle East amid the conflicts in Iraq and the Palestinian territories, where health officials were hard-pressed to respond. The disease also turned its wrath on Egypt, where denizens of Cairo, terrified to learn that chicken carcasses were being dumped in the Nile River, initially stopped drinking tap water. Soon Egypt would record more human cases and deaths than anywhere but Indonesia and Vietnam.
Then the disease crossed the desert to sub-Saharan Africa, infecting commercial farms in Nigeria and stoking fears that this indigent, ill-governed continent could become an entirely new breeding ground for a pandemic strain. Nigeria’s information minister told reporters, “While it was originally suspected that migratory birds may have been the purveyor of this disease, preliminary reports recently obtained from relevant security agencies indicate that there is a strong basis to believe that avian flu may have been introduced into Nigeria through illegally imported day-old chicks.” Scientists who later decoded the genetics of Nigerian samples concluded the virus had been introduced to the country three separate times along routes coinciding with the flight paths of wild birds. But the study also said imports could not be ruled out as the cause.
Once the virus was established in Nigeria, the epidemic spread, most likely along internal trade routes, and put neighboring countries in jeopardy because of widespread cross-border commerce. By the close of 2007, eleven African governments had reported outbreaks in birds, some in countries no better able than the poorest in Asia to confront the disease.
A rancorous debate has erupted over exactly how avian flu spreads.
Are wild birds the culprit, conveying the virus on their seasonal migrations? Or is it trade in poultry, legal or not, that inadvertently extends the global reach? Some wildlife conservation groups have said that migratory patterns aren’t a good match for the distribution of outbreaks, suggesting instead that the virus spread from Asia to Europe by commerce along the route of the Trans-Siberian Railroad. But other researchers have noted outbreaks near wintering sites for migratory birds and far from any farms or markets that could account for contamination. After more than a decade, there is now enough evidence to conclude that the novel strain has taken ample advantage of both these opportunities to advance across the Eastern Hemisphere.
Some countries have been able at times to roll back the tide of infection, notably those in Europe and more developed Asian states like Japan and South Korea. But elsewhere, the disease refused to surrender its foothold.
No one is better positioned to evaluate the viral storm gathering in the animal kingdom than Joseph Domenech, chief veterinarian of the UN Food and Agriculture Organization. In a series of public warnings starting in the fall of 2007 and running into 2008, Domenech offered a disturbing, though not universally bleak prognosis. “Surveillance and early detection and immediate response have improved and many newly infected countries have managed to eliminate the virus from poultry,” he reported. “But,” he continued, “the H5N1 avian influenza crisis is far from over.”
