Animal-based diseases account for 75 percent of newly emerging infectious diseases, including H1N1. Can health agencies work together to stop their spread?

One year ago this month, Dr. Anne Schuchat took the mike at one of the government’s first press conferences about a worrisome new flu outbreak. Schuchat, director of the Centers for Disease Control and Prevention’s National Center for Immunization and Respiratory Diseases, was trying to clarify what public-health officials knew about a virus that had sickened patients in Mexico and the United States. No, this was not bird flu, Schuchat told reporters listening in by phone from around the country that April day in 2009. That virus, technically known as H5N1, had been circulating since 1997, mainly in Asia. This was swine influenza, or, as it would soon be called, H1N1. “We’re talking about a new virus,” Schuchat said, referring to the novel form of H1N1, “a combination of a couple of different components of swine, human, and bird influenza.”
SUBSCRIBE Click Here to subscribe to NEWSWEEK and save up to 77% >>A cocktail of pig, bird, and human disease? That shouldn’t sound as surprising as it does. As many as 75 percent of newly emerging infectious diseases in humans, including bird and swine flus, are “zoonoses,” meaning they originate in animals. Other zoonotic killers include HIV/AIDS (transmitted to humans by wild African chimpanzees) and severe acute respiratory syndrome (bats). Even malaria, which was long thought to have evolved alongside humans, now appears to be zoonotic. After conducting genetic analyses, Nathan Wolfe, an infectious-disease expert at Stanford University, and colleagues reported last August that malaria started in chimps and jumped to humans sometime in the last 2 million to 3 million years. “This is a pattern we’ve seen for the origin of major diseases,” says Wolfe, “and it’s a pattern we’re seeing for new pandemics.”

This pattern has not, however, translated to adequate public-health preparation. One big reason: we’re not looking hard enough for clues. A report published by the Institute of Medicine (IOM) and National Research Council last September, at the height of the H1N1 pandemic, found that there is “no single example” in the U.S. or anywhere else of a well-functioning zoonotic disease surveillance system—despite the fact that outbreaks of these diseases are increasing and they can spread rapidly, thanks to international trade and travel. Instead, public-health officials tend to respond to outbreaks as they occur, which is neither smart nor economically sound medicine. Millions have died from worldwide pandemics over the last 50 years: H1N1 has killed at least 17,000 people in the last 12 months; more than 25 million have died from AIDS since 1981. Worldwide economic losses from species-crossing diseases: $200 billion over the past 10 years. “The disease-du-jour approach can’t work,” says Dr. Gerald Keusch, co-chair of the IOM report and professor of international health at Boston University’s School of Public Health.
That approach prevails because of a longstanding split between medical disciplines. “We have absolutely failed to systematically and effectively connect the veterinary community with the human-health community,” says Keusch. Classic example: West Nile virus. In 1999, when Tracey McNamara, then head pathologist at the Bronx Zoo in New York, called the CDC to report a potential link between sick birds and sick humans, she says a CDC official told her “there was no possible relationship between the two events.”

It wasn’t always so. In the 19th century, physicians frequently studied zoology, and physicians and veterinarians collaborated, says Dr. Laura Kahn, a physician and research scholar at Princeton’s Woodrow Wilson School of Public and International Affairs. But by the 20th century, medical schools had become highly specialized. Today, animal and human health are taught independently, and the disciplines are fragmented at the uppermost levels. The Department of Health and Human Services (HHS) focuses on people, the Department of Agriculture on livestock. And while we have a CDC for people, says Kahn, there’s no CDC for animals. “We need to start thinking more creatively,” she says. “Animal health impacts human health.”
The IOM report calls for change, including co-training between veterinarian and human-health experts. The government, increasingly aware of the importance of connecting the two, is investing in international surveillance. In November the United States Agency for International Development (USAID) announced the launch of a $400 million, five-year Emerging Pandemic Threats program, with the goal of preempting or combating newly emerging animal diseases that pose a risk to human health. One major component is Predict, a project that focuses on improving wildlife surveillance. A host of wild animals, from chimps to bats, rodents, and birds, have transmitted viruses to humans, and yet wildlife has been largely understudied when compared with domesticated animals like pigs and cattle, says Predict director Stephen Morse, a pioneering expert in zoonoses at Columbia University’s Mailman School of Public Health. “We really don’t understand the ecology of these diseases,” says Morse. “I don’t think we fully understand the magnitude of possibilities.” Predict, he says, “begins the fulfillment of a longstanding dream, which is to better understand what’s out there and how we can identify and anticipate the next AIDS before it happens.”
Predict relies on pandemic warriors, and Nathan Wolfe is one of them. In 2008 he launched an aggressive surveillance program called the Global Viral Forecasting Initiative. GVFI, one of Predict’s partners, operates in emerging infectious-disease hot spots, including Cameroon, China, the Democratic Republic of the Congo, Laos, Madagascar, and Malaysia, where scientists are working hard to build local surveillance systems. Public-health officials in these locales teach hunters to collect blood from their prey, and they also screen hunters and other high-risk individuals, including those who work in live-animal markets, for viruses, bacteria, and parasites. Wolfe’s hope is that if a new microorganism appears in both humans and animals, the public-health community and local governments can work together to stop a novel disease before it hopscotches around the globe. “These are not just random occurrences,” says Wolfe. “There are ways we can more accurately predict pandemics and ways we can alter human behaviors to try to decrease their frequency. We’re actively out there doing that work.”
Global disease control requires awareness, money, and political will and commitment from governments and both the human- and animal-health communities. Various groups, including the Wildlife Conservation Society, have launched programs under the banner of a movement broadly referred to as One Health, which is aimed at spotlighting the problem, fostering collaboration among disciplines, and, ultimately, saving lives. Kahn is beating the drum through a group called the One Health Initiative, and last fall, a summit co-hosted in Washington by the National Academies and an organization called the One Health Commission gathered public-health officials, veterinary-medicine experts, and government higher-ups to tackle the challenges.
Which brings us back to H1N1. One year out, the disease hasn’t been as lethal as some health officials feared. But it did hijack public-health attention and critical resources. The fast-tracked vaccine production, the jostling for scarce inoculations last fall, the school shutdowns—what if all that could have been avoided? That might have been possible, says Marguerite Pappaioanou, co-chair of the IOM report and executive director of the Association of American Veterinary Medical Colleges. The virus had been circulating in swine for a number of years and probably jumped undetected to humans sometime in 2008 or early 2009, she says. Had there been better surveillance of disease in swine workers and immediate recognition of the first human case, control efforts could have been put into place earlier to prevent it from infecting others, she says, “thereby helping to prevent a pandemic.” What a different year it might have been.