Few scenes are as haunting as those seen in Haiti this week, with thousands of corpses blocking the streets and others being carted by bulldozers en masse and dumped into huge graves. The Pan American Health Organization (PAHO) now estimates that at least 200,000 people died in the earthquake that devastated the country on January 12, and the buildup of dead bodies seems practically endless. If there is some good news to be shared, it is that these bodies pose little health risk to Haiti's surviving residents and to the health workers who are taking care of them.
That dead bodies might be dangerous is a "myth that has been perpetuated time and time again," says Steven Rottman, director of the UCLA Center for Public Health and Disasters. After almost every major natural disaster in history, survivors and the media have voiced concern that corpses could transmit infectious diseases. But if the disasters have struck populations that have, for the most part, been vaccinated against major communicable diseases like measles, "the risk of dead bodies following natural disasters being a source for spreading infectious diseases is very, very small," Rottman says.
That's because people who die in natural disasters like earthquakes or hurricanes are typically healthy. "They may have other medical conditions, but they're not living with highly communicable diseases," he says. "They die from injuries."
Tropical diseases do exist in Haiti. But once people die, the viruses and parasites that have infected them die too, because these pathogens need a living host. (The bacteria that play a role in body decomposition, on the other hand, do thrive after death, but they are harmless.) As Claude de Ville de Goyet, former director of PAHO's Emergency Preparedness and Disaster Relief Coordination Program, wrote in the journal The Lancet, "On rare occasions when victims of a disaster are carriers of communicable diseases, they are, in fact, a far lesser threat to the public than they were while alive."
According to a study published in the Pan American Journal of Public Health in 2004, most of the pathogens that could infect relief workers and survivors—such as hepatitis and tuberculosis—die within a couple of days of their hosts' deaths. One big exception is HIV, which can live for almost a week; live HIV has been extracted from bodily organs as many as six days post-mortem.
But a low percentage of the adult Haitian population is infected with HIV—UNAIDS, The United Nations Joint Programme on HIV/AIDS, estimates some 2.2 percent—and relief workers do handle corpses with care. There is even a manual on how to do it: In 2009, the World Health Organization (WHO), in collaboration with the Red Cross and other public health groups, published Management of Dead Bodies after Disasters: A Field Manual for First Responders, which among other things suggests that workers wear gloves and boots when handling dead bodies, wash their hands frequently and avoid wiping their faces with their hands. Although dead bodies do not typically spread infections, they often do release fecal matter than can make people sick.
Because it can be difficult to shake the notion that dead bodies are dangerous, survivors and health officials in the aftermath of a disaster often dispose of dead bodies in an inappropriate manner: by burying victims before identifying them, or not allowing family members to honor their customary burial procedures. "Most people don't encounter death, certainly on this magnitude and with the disfiguring injuries that you see following a natural disaster like this," so they sometimes act rashly, Rottman notes.
It's also difficult to know how best to handle corpses when there are just so many of them. Sometimes, says Linda Degutis, director of the Yale University Center for Public Health Preparedness, burying them in mass graves really is the most humane way. "It's probably far more disturbing to have a lot of dead bodies laying around that aren't being moved and buried," she says. And if workers wait too long in the hopes that family members come forward to identify the bodies, they will start to decompose; in warm climates such as Haiti's, it can take as few as 12 hours for bodies to decompose so much that it's impossible to recognize the faces.
When burying the dead after natural disasters, the WHO manual notes that it is important to ensure that burial sites are at least 650 feet from drinking water sources. Otherwise, decomposed remains can contaminate the water. And it is also crucial to bury the bodies deep enough—at least 5 feet down—so that subsequent rains do not expose the bodies again.
Ultimately, Rottman says, the biggest threat to public health in Haiti right now does not stem from exposure to dead bodies, but from the lack of access to clean water and food. "The restoration of basic hygiene is just critical to suppress communicable diseases," he says. He hopes that the ongoing relief efforts will ultimately put Haiti's infrastructure back together so that it is stronger than it was before. "The mantra of disaster recovery is not to put it back the way it was before it happened, but to make it better and more resistant to subsequent hazards," he says.