The Fatal Strain (23 page)

Prathum helped Nikon gingerly hoist the trays into the truck bed. Three days a week, Prathum’s eggs were ferried to Bangkok, but this batch was headed for a closer market, about fifteen miles away. While Prathum calculated the tab on a small pad, Nikon returned to the back of his truck and began pulling out a separate set of empty trays. He deposited dozens of them in the barn for use later in the week. They were still soiled from the market. It was like addicts swapping dirty needles.

 

 

There was a time in the United States when chicken was a luxury, an indulgence for those weary of more affordable dishes like lobster and steak. Chicken was precious because it was relatively rare. In the ninteenth century, raising poultry was little more than a hobby for farmers’ wives, and in 1880, when the U.S. Census started counting chickens, they numbered only 102 million nationwide. By 2006, that number were butchered nearly every four days.

This American revolution would have been impossible but for a series of advances in animal husbandry, starting with the debut of commercially sold chicks in the late nineteenth century. Next came the development of artificial hatcheries, which lowered prices and brought chickens to selling weight faster. Companies specializing in feed emerged. Vitamin D was introduced to fight rickets. Broilers and later layers were shifted indoors, where temperature, lighting, and diet could be precisely calibrated, and then the birds were raised off the ground and confined to tiers of wire cages, where care and feeding
was even easier. But the watershed was the introduction in 1971 of a vaccine for a poultry plague called Marek’s disease, which was killing 60 percent of the birds. Chicken prices plummeted, further fueling American demand already on the rise for familiar reasons: population growth, increasing income, and urbanization.

In the United States, where chicken was fast replacing beef as the animal protein of choice, safety measures to prevent disease followed quickly. The U.S. Department of Agriculture launched an aggressive campaign to educate farmers about biosecurity. Many family farms were swallowed by integrated agriculture companies, which insisted on stricter practices to protect their operations. In Europe, which was experiencing a similar chicken boom, many farmers had turned to banks for financing and inked contracts with feed mills. Both demanded measures to safeguard their investments.

Asia, for the most part, has yet to follow suit. So today, birds in China and Southeast Asia are amassed in once unimaginable densities, often weakened by their stressful confinement and exposed to the whims and wrath of viruses like influenza. The tremendous amounts of feed, water, and human traffic required to maintain these flocks offer a generous avenue to infection. In the unnatural setting of intensive agriculture, chickens are more vulnerable to contagion because they are pressed together and housed atop one another’s droppings, which are a main way, if not
the
main way, birds transmit the virus. A year after bird flu’s arrival in Thailand, a study found that Thai commercial farms were at a significantly higher risk of infection than the small, informal flocks of several dozen poultry that villagers have raised in their yards for centuries.

It’s not only the
risks
of infection on large farms that are greater. So are the consequences. The lack of genetic diversity in many commercial flocks means that a virus that infects one bird can likely infect them all, offering abundant opportunities for microbes to reproduce. The chances for the virus to mutate as it skips from bird to bird are multiplied many times over. “Once an influenza virus invades a commercial poultry farm,” scientists warned, “it has an optimum number of susceptible poultry for rapid viral evolution.”

But researchers have also found there’s something even more perilous
than a country of dense commercial chicken farms. That’s one like Thailand, a country in transition, where commercial farms operate in the midst of extensive traditional flocks. These small holdings represent a vital link in the chain of infection. For the flu virus to migrate from its natural reservoir in waterfowl, it needs an initial toehold in domestic poultry. Asia’s traditional backyard farms, with their freely grazing birds and even fewer safeguards, offer just this opening. They are like kindling wood around the larger commercial farms. And the larger commercial farms, which have mostly sprung up near their markets, are concentrated around another vulnerable population: the unprecedented accumulation of humanity in the metropolises of East Asia.

As Jan Slingenbergh of the UN Food and Agriculture Organization and his fellow researchers write, “Agricultural practices have become the dominant factor determining the conditions in which zoonotic pathogens evolve, spread and eventually enter the human population.” More pointedly, the FAO said in 2008 that the rapid development of Asia’s poultry industry without due regard for animal health created a “virtual time bomb” that “exploded” with the outbreak of H5N1.

 

 

Sangwan Klinhom was a Thai country singer in the parts around Suphan Buri. His resonant tenor earned him a following, but little money. The tips couldn’t even pay the rent. “If you’re a singer, you’re very poor,” he explained. “Some die without a coffin.” So he eventually abandoned the circuit of farmyard weddings and cheap beer joints for the roving life of a duck herder.

When I encountered him in the shade of a coconut tree, Sangwan was rolling a homemade cigarette fashioned from a palm frond. He would occasionally glance up to check on his flock, nearly a thousand khaki Campbell ducks pecking and scavenging in the mucky waters of a rice paddy several miles north of Banglane village. Despite the intense midday heat, he wore a heavy brown knit cap with a blue pompom to keep the sun off his head. His brow was deeply furrowed, his jowls weathered. Beneath thick, graying eyebrows, his deep-set eyes were bloodshot from sun and stress. Once again, he was singing a plaintive tune.

The practice of grazing ducks in rice fields, which initially developed in southern China, had long since spread to the wetlands of Southeast Asia. Herders like Sangwan followed the rice harvest, trucking their flocks from province to province in pickups and feeding the ducks for free on residual grains, insects, and snails in the muddy water. “The ducks give you anything you want,” he told me. “If you want something, you wait a bit and you get it. I didn’t even have a house before.” But now this barefoot nomad and countless others like him were being pressed by Thai officials to renounce their wandering ways and shut their flocks up in closed shelters. Ducks had been fingered as silent killers.

Researchers had discovered that ducks were spreading the novel flu strain like never before while no longer displaying any symptoms of their own. Wild waterfowl had long been recognized as a natural host for flu viruses, carrying the infection without getting sick. As the pathogen grew more virulent, it initially turned on the cousins of these wild birds, domesticated ducks, and caused widespread die-offs. For a while, this helped tip public health officials to proliferating poultry outbreaks that could endanger people. But in 2004, the virus abruptly changed its modus operandi a second time. Infected ducks once again showed no symptoms, according to an international team of scientists based at St. Jude Children’s Research Hospital in Memphis. But now these infected birds spread the virus in larger amounts and for longer periods, in some cases a week longer than before. The virus also survived for more time in the surrounding water than it ever had. The duck had become “the Trojan horse” for Asian flu viruses, the researchers warned darkly.

When investigators in Thailand tested flocks of free-range ducks, nearly half proved to be infected with flu despite few signs of illness. Scientists warned that traditional duck farming posed a tremendous risk not only in Thailand’s central plains but also in the Mekong River delta of southern Vietnam and the Red River delta of northern Vietnam.

Separate studies of the bird flu epidemic in Thai poultry had also deeply implicated free-ranging ducks. The research showed that outbreaks in the chicken population were concentrated in areas where
ducks commonly graze, primarily wetland areas of intensive rice cultivation. Suphan Buri was singled out as a hot spot for disease. By contrast, provinces with high concentrations of chickens but few ducks largely escaped the brunt of the epidemic. The authors suggested that paddies were a likely meeting point where migratory water birds relayed contagion to ducks, which in turn infected chickens before shuttling it to other fields and provinces.

Sangwan said his rambling took him through the rice paddies of more than ten provinces over the course of a season. Every two or three days he moved on, generally drifting southward with the harvest. Only hours earlier, after exhausting the pickings in a nearby field, he had herded his flock to a new paddy, where young rice plants were just starting to poke through the still surface. “I marched them here like little soldiers. ‘Keep walking,’ I told them. ‘Keep walking.’ ” He gestured with his open palms to show how he nudged them along, a smile settling on his stubbly face and crow’s-feet deepening at the corners of his eyes. The ducks had filed down the grassy banks into the water, waddling and ruffling their tail feathers. A flotilla set sail with a whoosh toward a low line of palms on the distant shore. Sangwan had claimed a rare sliver of shade on the dike. He lay down his long bamboo rod and stretched out his scrawny legs.

At the end of the day, Sangwan and his wife would line the birds up again and march them back to the campsite. The ducks spent their nights in a temporary enclosure of plastic sheeting. Sangwan looked for a dry patch of earth to pitch his tent. “I’ve gotten used to living in the open fields,” he said. “I love spending the time with the ducks rather than in a house, where you have to hear a television and people talking and traffic on the street.” In the hours before dawn, he would listen to his charges rustle as they scouted for comfortable nooks to lay their eggs. “That’s a nice sound,” he mused. “That’s the sound of making money.”

Sangwan had turned to herding two decades earlier as the livestock revolution was accelerating, doubling and redoubling Thailand’s duck production. As a younger man, he had dabbled in construction, growing rice, and raising vegetables. He took up singing after winning a local contest. Later, dead broke, he persuaded his uncle to teach him
about ducks. He learned how to call to them in an authoritative voice so they’d respect and obey him. But alone on the dikes, Sangwan still serenaded his flocks with ballads of rural heartbreak.

Lowering his cigarette to his side, his melancholy voice began to carry across the glistening paddies, rising above the soft swooshing sound of birds foraging in the water.

He returned the cigarette to his lips and took a long drag. His sunken cheeks slipped even deeper into shadow. Then he continued.

He paused again, briefly, eyes lowered.

When he finished, Sangwan drew a bag of tobacco from the pocket of his baggy shirt and began rolling another cigarette. He fretted that the best days seemed to be over. Thai officials were already threatening to restrict the movement of ducks from one village to another. He could never afford to raise his flock in a closed shelter, he said. The feed bill would bankrupt him and the ducks would rebel.

After the government first floated the idea in late 2004, Sangwan had experimented with confining the ducks to a shed beside his house. It lasted a week. “I felt restless because the ducks couldn’t walk around
and they didn’t have enough food,” he recounted. “The ducks were not happy.” That was bad news for business because, he confided to me, ducks are like pregnant women. They need to be pampered or they get nervous and lay their eggs prematurely. “I feel like I have a thousand little wives,” he said, a grin briefly breaking through. “When the ducks get tense, I get tense.”

To protest the proposed farming regime, his wife had led hundreds of peasants to the provincial capital. They besieged a government building for three hours, accusing officials of acting arbitrarily and sowing needless anxiety. “When the government says ducks carry bird flu, it just makes people panic,” Sangwan complained, growing agitated. “It’s not true that ducks get the flu. For twenty years I’ve been raising ducks and I’ve never seen one get bird flu.”

In the months after I met Sangwan, the Thai government would bar farmers from transporting their flocks from one region to another and eventually, in 2006, place a total ban on duck grazing. Thailand’s initiative sputtered, but the country ultimately achieved more than neighbors like Vietnam, China, and Indonesia, where duck herding remains common. When flu outbreaks unexpectedly erupted across more than a dozen provinces of northern Vietnam in 2007 after a long period of quiet, sickening people in the country for the first time in eighteen months, ducks were implicated. A special investigation blamed the epidemic on a dramatic influx of young ducks into the paddies of the Red River delta. By contrast, many of the estimated 10 million free-range ducks in Thailand were ultimately slaughtered or moved indoors.

But even there, compliance was spotty. Some Thai duck herders continued to follow the cycle of the crops as they had for generations, thwarting efforts to snuff out the disease. It had been several harvests since I met Sangwan when I heard about a group of herders who’d illegally moved three flocks with as many as fifteen thousand birds into the fields of Kanchanaburi province, just west of Suphan Buri. The chickens in several local villages began to die within two weeks. When those near the home of a peasant named Bang-on Benphat started to fall sick and collapse, the forty-eight-year-old man butchered them for dinner. His young son helped pluck the feathers. Both
soon developed a fever and lung infections. Bang-on was hospitalized with severe pneumonia. Two days later he died, a casualty of flu.