primrose path at the expense of having real viruses with which to work.
The paper was a collaborative effort but that sentence sounds like Charlie Calisher. What it means is: Hello, people? We’ve gotta grow these bugs the old-fashioned way, we’ve gotta look at them in the flesh, if we’re gonna understand how they operate. And if we don’t, the paper added, “we are simply waiting for the next disastrous zoonotic virus outbreak to occur.”
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Charlie Calisher and his coauthors, besides touching on broad principles, discussed a handful of bat-related viruses in detail: Nipah, Hendra, rabies and its close relatives (the lyssaviruses), SARS-CoV, and a couple of others. They mentioned Ebola and Marburg, though carefully omitting those two from the list of viruses for which bats had been proven to serve as reservoirs. “The natural reservoir hosts of these viruses have not yet been identified,” they said about Marburg and Ebola—accurately, as of the time of publication. Their paper appeared in 2006. Fragments of Ebola RNA had been detected by then in some bats; antibodies against Ebola virus had been found in other bats. But that wasn’t quite proof enough. Nobody had yet isolated any live filovirus from a bat, and the unsuccessful efforts to do so left Ebola and Marburg well hidden.
Then, in 2007, Marburg virus reappeared, this time among miners in Uganda. It was a small outbreak, affecting only four men, of whom one died, but it served as an opportunity to gain new insight into the virus, thanks in part to a quickly responsive multinational team. The four victims all worked at a site called Kitaka Cave, not far from Queen Elizabeth National Park, in the southwestern corner of Uganda. They dug galena, which is lead ore, plus a little bit of gold. The word “mine” caught the attention of some scientists within the CDC’s Special Pathogens Branch, in Atlanta, because they already had reason to suspect that Marburg’s reservoir, whatever it was, might be associated with cavelike environments. Several of the previous Marburg outbreaks included patients whose case histories involved visits to, or work in, caves or mines. So when the response team arrived at Kitaka Cave, in August 2007, they were ready to go underground.
This group included scientists from the CDC, the National Institute for Communicable Diseases in South Africa, and WHO in Geneva. The CDC sent Pierre Rollin and Jonathan Towner, whom we’ve met before, as well as Brian Amman and Serena Carroll. Bob Swanepoel and Alan Kemp of the NICD flew up from Johannesburg; Pierre Formenty arrived from WHO. All of them possessed extensive experience with Ebola and Marburg, gained variously through outbreak responses, lab research, and field studies. Amman was a mammalogist with a special affinity for bats. During a conversation at the CDC, he described to me what it was like to go to Kitaka Cave.
The cave served as roosting site for about a hundred thousand individuals of the Egyptian fruit bat (Rousettus aegyptiacus), a prime suspect as reservoir for Marburg. The team members, wearing Tyvek suits, rubber boots, goggles, respirators, gloves, and helmets, were shown to the shaft by miners, who as usual were clad only in shorts, T-shirts, and sandals. Guano covered the ground. The miners clapped their hands to scatter low-hanging bats as they went. The bats, panicked, came streaming out. These were sizable animals, each with a two-foot wingspan, not quite so large and hefty as the flying foxes of Asia but still daunting, especially with thousands swooshing at you in a narrow tunnel. Before he knew it, Amman had been conked in the face by a bat and suffered a cut over one eyebrow. Towner got hit too, Amman said. Fruit bats have long, sharp thumbnails. Later, because of the cut, Amman would get a postexposure shot against rabies, though Marburg was a more immediate concern. “Yeah,” he thought, “this could be a really good place for transmission.”
The cave had several shafts, Amman explained. The main shaft was about eight feet high. Because of all the mining activity along there, many of the bats had shifted their roosting preference “and went over to what we called the cobra shaft.” That was a smaller shaft, branching off, which—
I interrupted him. “ ‘Cobra’ because there were cobras?”
“Yeah, there was a black forest cobra in there,” he said.
Or maybe a couple. It was good dark habitat for snakes, with water and plenty of bats to eat. Anyway, the miners showed Amman and Towner into the cave, past another narrow shaft that