the BSL-3 suites, and then soon the BSL-4s. She began working with live Ebola virus.
Much of her effort went into the VLP research, though she also helped on other projects within her boss’s lab. One involved testing a form of laboratory-created antibodies that might serve as a treatment against Ebola virus disease. These antibodies, developed by a private company in collaboration with USAMRIID, were designed to thwart the virus by tangling with a cellular protein involved in viral replication, not with the virus itself. It was a clever idea. Warfield again used mice as her test animals; she now had years of experience at handling and injecting them. For the experiment she infected fifty or sixty mice with Ebola virus and then, during the following days, gave them the experimental antibody treatment. Would they live, would they die? The mice were kept in clear plastic cages, like tall-sided pans, ten mice to a pan. Methodical procedures and constant attention are crucial to BSL-4 work, as Warfield well knew. Her methodical procedures for this experiment included filling a syringe full of antibody solution, enough for ten doses, and then injecting the ten mice from each pan with the same syringe, the same needle. It wasn’t as though cross-infection was a concern, since they had already been dosed with the same batch of Ebola. Dosing multiple mice with a single syringe saved time, and time in a BSL-4 lab adds up toward stress and increased risk, because the physical circumstances are so difficult.
Picture those circumstances for Kelly Warfield. Customarily she worked in the BSL-4 suite known as AA-5, off a cinderblock corridor in the most secure wing of USAMRIID, behind three pressure-sealed doors and a Plexiglas window. She wore a blue vinyl protective suit (she and her colleagues simply called them “blue suits,” not spacesuits or hazmats) with a fully enclosed hood, a clear face shield, and a ventilation hookup. Attached to her hookup was a yellow hose, coiling down from the ceiling to bring filtered air. She wore rubber boots and two pairs of gloves—latex gloves beneath heavier canners gloves, sealed to her suit at the wrists with electrical tape. Even with canners gloves over latex, her hands were the most vulnerable part of her body; they couldn’t be protected with vinyl because they had to be delicately dexterous. Her workbench was a stainless steel cart, like a hospital cart, easy to clean, easy to move. If you didn’t love the work, you wouldn’t put yourself in this place.
She was alone in AA-5, under exactly those circumstances, at five thirty on the evening of February 11, 2004. She had come late to the day’s tasks for the Ebola experiment because earlier hours had been filled with other demands. One pan of mice sat on her cart, along with a plastic beaker, a clipboard, and not much else in the way of materials and tools. It was the last pan of mice for the day. She filled a syringe and carefully injected nine mice, one after another—gripping each animal by the skin behind its neck, turning it belly up, inserting the needle into its abdomen deftly, quickly, adding no more discomfort than necessary to the life of each doomed and Ebola-ridden mouse. After each injection, she placed that mouse in the beaker, to keep the finished group apart from the others. One mouse to go. Maybe she was a little tired. Accidents happen. It was this very last mouse that caused the trouble. Just after being injected, it suddenly kicked away the needle, deflecting the point into the base of Kelly Warfield’s left thumb.
The wound, if there was a wound, seemed to be only a very light graze. “At first, I didn’t think that the needle went through the gloves,” she told me. “It didn’t hurt. Nothing hurt.” Remaining calm by an act of discipline, she set the mouse back in his pan, put the syringe away, and then squeezed her hand. She could see blood emerging under the layers of glove. “So I knew I had stuck myself.”
We were seated at her dinette table, on a mild September afternoon, as she talked me through the events of that February day. The house, which she shared with her Army-physician husband and her young son, was light and cheery with a lived-in feel; there were pieces of kid art on the refrigerator, a few toys lying around, a large green backyard, two half-poodle dogs, and a sign on the kitchen wall commanding: DO