Africa's Deadly Visitor
By May 17, the same hideous illness had killed 77 people in Kikwit—nearly two-thirds of them hospital staff. Alerted by concerned Zairean health officials, the World Health Organization in Geneva dispatched a team of tropical-disease experts to Kikwit, a city of 500,000 that lies 370 miles east of Zaire's capital, Kinshasa. On May 11, the Centers for Disease Control and Prevention in Atlanta, having tested blood samples sent from Zaire, identified the cause of the outbreak as the Ebola virus. Scrambling to contain the deadly pathogen, Zairean authorities set up roadblocks outside Kikwit, stopping all travel in and out of the city.
The news jarred a public already nervously alert to viral risk, thanks to two recent nonfiction best-sellers (The Hot Zone, by Richard Preston, which details a 1989 Ebola outbreak among monkeys in Reston, Va., and The Coming Plague, by Laurie Garrett, about emerging diseases), as well as two alarmist movies (Outbreak and NBC's Virus). Though public awareness of Ebola has come only recently, the disease was first identified in 1976, when an outbreak killed more than 400 people in northern Zaire and neighboring Sudan. The virus erupted again in Sudan in 1979, and earlier this year an isolated case occurred in the Ivory Coast.
Among the epidemiologists most familiar with Ebola is Dr. Peter Piot, 45, executive director of the Joint United Nations Program on AIDS in Geneva. Piot, a Belgian, was a 27-year-old research scientist at the Institute for Tropical Medicine in Antwerp when he and colleagues codiscovered the virus in 1976. Now overseeing programs against AIDS for developing countries, Piot lives in Geneva with his wife, Greet, a psychologist, and their two children, Bram, 18, and Sara, 14. He spoke with correspondent Ellen Wallace.
How did you discover the Ebola virus?
I was training in microbiology in Antwerp in 1976, when we received samples of liver and blood from a nun who had died in Zaire. The diagnosis was yellow fever, but when we grew a culture we saw it was very different from the yellow fever virus. The Centers for Disease Control in Atlanta confirmed that the virus was unlike anything that had ever been documented. The next day I caught a plane to Zaire to join an international team that was investigating the outbreak. We had no clue to what had caused it.
What did you find when you arrived in Zaire?
I joined the team in Kinshasa, and we traveled to Yambuku in the epidemic area near the Ebola River in northern Zaire. It was exactly the same picture as we've seen in Kikwit: outbreaks around the mission hospital involving a lot of health-care workers.
How is Ebola transmitted?
We know that it is transmitted through contact with blood or other body fluids and by injections with needles contaminated with the virus. I suspect there may be sexual transmission as well. Both the current outbreak and the one in 1976 occurred at hospitals where basic sanitary precautions—sterile needles, gloves, masks—aren't available. In 1976 the hospital where Ebola broke out had three syringes for 120 beds. When you use the same needles over and over, the risks increase significantly.
How is Ebola contained?
The hospital where the virus was reported in Kikwit was immediately closed to everyone except patients with Ebola. A team of doctors—from the CDC, the World Health Organization in Geneva and the Institut Pasteur in Paris—gathered in Zaire days after the outbreak and is now helping isolate known cases of Ebola infection, going into communities to search out victims before they infect other people living in their homes.
What can be done for Ebola victims?
Not very much, other than keeping the patient as comfortable as possible. They usually become ill within a week after infection; 90 percent are dead a week later.
What are the origins of the virus?
Where Ebola comes from is a very big question mark. The virus first appeared in Central Africa, close to tropical rain forests—areas where there may be more interaction between people and animals. With increasing deforestation, people may be coming into contact for the first time with animals that carry the virus.
Might humans be such carriers?
No. The ideal host for a virus lives a long time, as is the case of humans with HIV, for example. A host who dies after two weeks is not a good host, because the virus dies with the host.
Should we be worried about Ebola spreading outside Zaire?
Viruses like Ebola may be spectacular because the mortality is so high, but they're also usually isolated. The number of people affected is normally in the hundreds, compared to an epidemic like AIDS, which affects 20 million. You might get a few cases of Ebola in Europe or North America, but because the disease progresses so swiftly, its victims soon become too ill to be effective transmitters of the virus. I don't think you could have major, major disasters. It's not like in the movies.