Taking Fruit Bats Off the Dinner Menu to Reduce Ebola Risk
Posted by Richard Conniff on October 25, 2014
Except at Halloween, when they appeal to our sense of the ghoulish, it’s never easy to get people to care about bats. Yes, they are mammals. Yes, in the case of fruit bats, they are cute, warm-eyed mammals at that, the sort of thing that makes seals, pandas, tigers, elephants, and other “charismatic megafauna” the poster children of conservation fund-raising campaigns.
But bats are decidedly not in this category. You might just persuade people that they aren’t the bloodsucking monsters of their nightmares by reminding them that only three of the 1,250 bat species in the world are vampire bats. (Even those three mostly lick blood from open wounds, rather than sucking blood, Dracula style.) But then the story really turns ugly, because bats, and particularly fruit bats, are also the most common source of new and terrifying diseases, including SARS, Nipah and Hendra viruses, Marburg and Lassa hemorrhagic fevers, and Ebola, which turned up this week in New York City.
Epidemics of emerging disease have a way of fostering rumors and hysterical overreaction. Much as in the Middle Ages, when cats went on trial for witchcraft, wildlife often serves as a handy scapegoat. During a 2012 outbreak in Uganda, for instance, the minister of tourism, of all people, announced a plan to cull wild animals in national parks.
“We shall eliminate animals suspected to be carrying viruses of Ebola and Marburg,” Maria Mutagamba boldly declared. Never mind that tourism, based almost entirely on wildlife, is one of Uganda’s leading sources of foreign revenue. A wildlife official quietly wondered just how Mutagamba planned to accomplish her cull, given that at the very least, tens of thousands of animals inhabit these parks and do not readily line up for blood tests.
A better answer in an age of emerging diseases is not to interfere with the animals in the first place. But that often turns out to be surprisingly difficult too. For instance, a recent study in the journal EcoHealth looked at the appetite for straw-colored fruit bats as bush meat in the West African nation of Ghana. This species (Eidolon helvum) is known to carry a variety of diseases transmissible to humans, including henipaviruses, paramyxoviruses, lyssaviruses, and the big one, Ebola. Yet Ghanaians just in the southern part of the country hunt and eat about 128,000 of them every year. The species is in significant decline as a result.
The researchers found that bat hunters typically don’t use any sort of protective gear against bites or scratches, nor do they believe that they are at risk for any diseases. In some cases, when a large branch fell under the weight of its load of bats, rival hunters would fight for the catch, sometimes even lying down on top of bats to prevent others from taking them. People who ate bats commonly said they did because the meat tastes good when smoked or cooked as a kebab, or even when made into a soup with bat intestines. Bat meat also enjoys an improbable reputation as an especially healthy food (and low in cholesterol). It’s a subsistence food for some in the absence of other affordable protein sources. For others, it’s a luxury.
Ghana has managed to escape Ebola so far this year, but the alarming spread of the epidemic through five neighboring countries has the government rolling out a nationwide educational program.
That makes the new study particularly relevant, because it focused on the effectiveness of an educational program in changing people’s behavior. Such programs need to start by identifying people most likely to engage in the relevant behaviors, according to the study, and also take into account local perceptions and cultural beliefs that can affect management of an outbreak. The study tested a brief educational program that focused not just on the health risk of consuming bats but also on the environmental value of the bat population.
Bats are the primary pollinators of many tropical plants, and they disperse the seeds from fruit they eat. In Africa and Asia, that makes fruit bats “responsible for about 50 percent of the tropical rainforest there,” said Jonathan Epstein, a veterinary epidemiologist at EcoHealth Alliance, who did not participate in the study. It’s a double whammy: You can get sick to death from eating the bats, and the loss of the fruit bat population could hurt other aspects of the environment on which residents depend for their survival.
The program dramatically increased the percentage of people who believed that bats could make them sick or that bats could be environmentally beneficial. But only about 55 percent of those who hunted, butchered, or sold bats said the program was likely to change their behavior. As with cigarette smoking, unsafe sex, and a long list of other behaviors, “people can readily perceive risk and even intellectually acknowledge desire to reduce that risk,” the researchers reported, and yet not do anything about it.
While some laws limit bat hunting, the researchers also found that “essentially no one knew of the existing hunting laws in Ghana” and that “laws and fines alone are unlikely to induce change.” In the end, the study found, “there may not be a simple way to minimize the risks of zoonotic spillover from bats.”
Even if it is complex and expensive, the current epidemic makes it clear that stopping emerging diseases at the source remains the only way to prevent a pandemic here at home. What to do? When people depend on a food like bat meat for survival, said Epstein, “it’s not realistic to just take it away and not present an alternative.” A better way to minimize disease risk might be to extend the effort to instruct people in the vital importance of wearing protective gear while hunting, and of washing their hands thoroughly after preparing bats for the table.
One certain way not to protect ourselves is to cut funding to the very agencies that perform that kind of difficult training and monitoring around the world. That’s what happened as a result of the recent Republican sequester, with its indiscriminate across-the-board budget cuts. The National Center for Emerging and Zoonotic Infectious Diseases, which has led the United States’ intervention in West Africa, lost $13 million from its 2013 budget as a direct result. Now it’s estimated that it will cost at least $600 million—and thousands more lives—before we can stop this epidemic.
With Ebola present in Dallas and New York, this is one of those times when investing in good government can make a life-or-death difference for us all. Keep that in mind a few weeks from now, when you cast your vote on Election Day.