The Virus, the Manatee, and the Biologist

Early on a summer morning in northern Florida, four of the world's most endangered mammals, looking a lot like gigantic gray Idaho potatoes, crowd together at the bottom of a concrete pool, gently bumping into one another as the green ocean water drains away beneath them. Two veterinarians and a physician peer down at white spots on the animals' skin. Then they descend concrete stairs into the eight-foot-deep pool and start to work, surrounded by a dozen assistants and chattering spectators. The 1,500-pound manatees lie still. Gregory Bossart, tanned, blond, and barefoot, rubs disinfectant on the manatees' lesions, sprays them with alcohol, and carefully slices them away with a scalpel. He is a vet, a wildlife pathologist, and the director of marine mammal research and conservation at the Harbor Branch Oceanographic Institution in Fort Pierce, on the other side of the state. Alfred Bennett Jenson, a white-haired M.D. from the Brown Cancer Center in Louisville, Kentucky, whisks tissue samples into an open bottle. Meanwhile, Mark Lowe, the consulting vet here at Homosassa Springs Wildlife State Park, bends over the pectoral fin of a manatee named Holly to take a blood sample. When he jabs her with a needle, she flips her flat, powerful tail, tossing a wet-suited keeper into the air. He lands back on top of her and grabs hold again. By the time the three doctors have finished their work, the sun is high and the pool is as hot as a sauna. Jenson, with sweat running down his face, packs up his box of tissue specimens. Lowe leans back and lights a pipe. He was the first to notice the lesions, back in 1997. He sent the samples to Bossart, who was quite surprised when they turned out to be Papillomavirus, which had never been detected in a manatee. The virus causes warts and benign tumors, which are communicable. More than 100 types of the virus have been found in people. In women the virus can transmute into cervical cancer, a disease very much on the mind of Partha Basu, who has come all the way from Calcutta to observe. He is head of gynecological oncology at the National Cancer Institute of India, where he sees four or five new cases of cervical cancer each day. Two years ago, when he saw what he had, Bossart called Jenson, an immunopathologist. Although Jenson had studied Papillomavirus in snow leopards, he had never heard of a manatee carrying the virus. When he examined the tissue samples Bossart sent him, he was stunned. "I thought I'd seen everything," he says, removing his red baseball cap and rubbing his hair. "This is important, really a harbinger of bad news. Something bad is going on." Jenson says that if he can learn how the virus works in manatees, that knowledge might lead to improved treatment for humans. Cervical cancer is the second leading cause of death from cancer among women. Three vaccines for human Papillomavirus have been developed, one by Jenson and Richard Schlegel of Georgetown University. But vaccines are helpful only to people who have never been exposed to the virus, and it will be 20 years before the vaccine has a significant impact on death rates. Many of those exposed to the virus remain carriers for life. "If we can determine why manatees can't clear the virus," Jenson says, "then that is probably the same reason why humans can't clear the virus."