Like many livestock farms in southern China’s Guangdong province, this one probably isn’t licensed by the local authorities. The farm manager, a short and stern woman, would allow visitors only on the condition that she and the farm remain anonymous. And unregulated farms aren’t the only places where people and animals live cheek by jowl on the mainland. Walk through the door of Guangzhou’s Bai Wen Xian restaurant, for instance, and the first thing you notice is the zoo-like stench. Animal cages stacked just inside the doorway hold whatever happens to be on the evening’s menu–snake, chicken, duck, rabbit, even a cute black kitten. For the equivalent of about $1, the chef will promptly take the animal of your choice upstairs, slit its throat, skin it and stew it. “The most popular dishes,” says 19-year-old waitress Lai Donghua, “are the bird dishes.”

If you wanted to create an environment ideal for manufacturing new diseases and spreading them rapidly throughout the world, it would be hard to beat southern China. Animals and humans pass viruses between them like business cards at a sales convention, which gives the bugs plenty of opportunities to morph from benign viruses into deadly pathogens. Scientists don’t yet know exactly how the recent outbreak of SARS (severe acute respiratory syndrome) occurred, but they’re pretty sure it got its start in southern China. If SARS made the leap from animal to human, the region’s dense population would’ve given it plenty of fodder to grow. And daily flights from the provincial capital, Guangzhou, to international travel hubs Beijing and Hong Kong are excellent conduits abroad.

The sine qua non of the SARS outbreak, though, has been Beijing’s policy of secrecy. When SARS first arose, probably in November, Chinese authorities never reported the unusual outbreak. The World Health Organization got wind of it only when Dr. Carlo Urbani discovered the disease in Hanoi in February. Those few months gave the disease a critical head start. In recent weeks health officials have announced several times that they’d gotten things under control, only to be surprised by new outbreaks. “We’re still not sure if SARS is going to become a pandemic,” says Dr. David Heymann, WHO’s head of infectious diseases. Scientists at Fort Detrick in Maryland found that interferon, a protein –that boosts the immune system, might be a promising treatment. Nevertheless, last week the disease’s toll approached 3,000 cases and 121 deaths. Scientists now say there’s a chance SARS may never be eradicated–that it will take its place alongside tuberculosis and malaria as a permanent human affliction. If so, Beijing will have been an accomplice.

What’s got health officials even more rattled is the disaster that hasn’t happened, but may still. SARS is serious, to be sure, but it’s not the worst disease that could come from the petri dish of southern China. The influenza pandemic of 1918, which killed 20 million people, makes SARS look like the sniffles by comparison. If things don’t change, health officials fear, the country will only continue to export new pathogens. And as the genetic dice continue to roll, the likelihood of a truly devastating new disease continues to increase.

The first step to preventing the next outbreak, of course, is figuring out what caused this one. Last week a team from WHO concluded their first investigation into the SARS epidemic in Guangdong. They made little headway into tracing the origins of the disease. The leading theory is that SARS originated, like most influenza viruses, in aquatic birds (ducks, perhaps) and then made the jump to humans. Although SARS is a coronavirus, like the common cold, its origin in southern China implies a zoonotic pathway similar to influenza’s. If SARS started as a water-borne bird virus, it might have gotten passed via fecal droppings to a chicken or a pig, or even directly to people. Along the way, the original virus probably mutated spontaneously and exchanged genes with viruses from other animals, acquiring new characteristics.

The precise characteristics of the SARS virus have been tough to nail down. Scientists know that it can pass from person to person. Like a cold virus, it can linger for hours on a doorknob or other object, and it doesn’t appear to spread as quickly as influenza. Scientists, though, are still perplexed by the pattern of outbreaks. When hundreds of residents of an apartment block in Hong Kong came down with the illness, scientists worried that the virus might be able to spread over long distances through the air. They’ve since discounted that possibility. Now they think SARS may spread not only through sneezing and coughing, but also through feces, which could linger in dirty water or spread from cockroaches or rodents, and through the blood supply.

–Like the 1997 bird flu, many viruses start out as water-borne bird viruses and jump directly to humans. It’s easy to see how. In Guangdong, duck farmers live in close quarters with their flocks. Liu Hai, a spry, friendly 21-year-old, lives with his father, mother and grandfather on the edge of a pond, where they raise several hundred gray ducks destined for Guangdong’s restaurants. Home is a plastic tarp thrown over a frame of chicken wire which abuts the pen. The family can keep close tabs on their flock simply by peeking through the wire mesh.

Liu’s habits may help explain just how easy it is for a virus like SARS to make its way around Guangdong. One of the ironic twists to this epidemic is that the first person in China to die of the disease lived in Shanglang, a tidy town whose streets are free of trash and where chicken cages are rare. Ringing the outskirts of town, though, are factories that increasingly attract workers from rural areas, a trend that will only grow as China’s economy booms. Liu himself holds a factory job in Guangzhou–in part, he says, to escape the cramped quarters of the family’s duck farm. Each week he rides a bus for two hours and stays over in a factory dorm room with eight other workers. Scientists now think it’s possible that people like Liu, who travel between farms and factory towns, but show no symptoms of the disease, can carry it unwittingly.

The WHO team which left Guangzhou last week tried to put a diplomatic face on the situation. “It could be days, it could be months, it could be years” before they discover SARS’s origins, says Dr. Wolfgang Presier, a virologist from Goethe University in Frankfurt. “It may never happen.” More vexing, health officials aren’t sure if efforts to isolate SARS will contain the disease in China. Without good diagnostic tests and vaccines, officials rely on isolating infected people to keep transmission down.

In Guangdong, though, the SARS outbreak has strained the health-care system. In February the Guangdong Infectious Disease Hospital was designated to receive SARS patients. They quickly overwhelmed the wards, filling 150 of 400 beds. Other designated-SARS hospitals filled up as well, forcing local hospitals to set up makeshift isolation wards. Patients with pneumonia symptoms have been reluctant to stay in the wards for fear of catching SARS, if they don’t already have it. Many small hospitals have gone lax on precautions. Villagers in Shanglang seem blissfully unaware that they live at the epicenter of a global disease. No one wears a mask, not even the doctors. “The hospital doctors are required to wear masks,” says Dr. Chen Kuchun, “but since I haven’t seen anyone with symptoms, I stopped wearing one.” Says Yin Chibiao, vice director of the Number Eight People’s Hospital in Guangzhou: “Maybe it’s not good for a society to get too nervous. China is still a poor country. The Chinese can’t take as much care as, say, the Americans.”

Despite Beijing’s rare public apology, the government has failed to convince health experts that it will act differently the next time a new disease arises. For China’s rulers, papering over news that makes the Communist Party look bad–from famines to mine disasters to collapsed dams–has been a way of life for decades. For years Beijing even denied the country had an AIDS problem, even as the number of cases exploded. “The handling of the SARS outbreak shows that China learned nothing from the AIDS experience,” says a Western health-care worker in Beijing. The government continues to try to give SARS a positive spin. The state media reports that the disease is under control, and a publisher has put out a book called, “SARS Is Nothing to Be Afraid Of.”

That facade took a hit last week, when Dr. Jiang Yanyong, the 72-year-old former director of the People’s Liberation Army Hospital No. 301, accused the Ministry of Health of deliberately lying about the prevalence of the disease in the Chinese capital. Chinese health officials flatly denied last week that they had hid the facts.

And in the meantime China shows no signs of promoting the WHO’s warning to avoid unnecessary travel to southern China. The May 1 holiday, which Chinese traditionally celebrate by traveling home to the countryside, is proceeding as scheduled. Sun Gang, deputy director of the National Tourism Administration, told the People’s Daily: “A well-organized holiday, with millions of people traveling around this vast country, will show the world that tourism in China is secure and healthy.” It’s a fantasy the rest of the world could do without.