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Seven months after she left the hospital, a news article caught her attention. A Dutch woman who had also traveled to Uganda had died from Marburg hemorrhagic fever, a viral disease. She was thought to have contracted it from exposure to bats and their droppings in the Python Cave, in the Queen Elizabeth National Park in Uganda. (The cave has since been closed.) Ms. Barnes had visited the same cave. Although she had already been tested for Marburg, she asked Dr. Fujita to test her again. This time, more sensitive tests were used, and they came back positive.
It was a sobering result. The Marburg virus had never before reached North America, as far as experts know. It is a close relative of Ebola, and the diseases these viruses cause are among the world’s most dreaded, because they can have horrific symptoms and high death rates and are easily transmitted by bodily fluids. There is no vaccine, cure or even specific treatment.
Infectious disease experts had warned for years that someday an infected person might board a plane and carry one of these deadly viruses halfway around the world, potentially exposing countless others along the way. Now it had happened. But Ms. Barnes survived, and no one else became infected, even though epidemiologists calculated that 260 people — hospital and lab workers, friends and family — had potentially been exposed.
The first detailed report on her puzzling case was published in the Dec. 18 Morbidity and Mortality Weekly Report, by the Centers for Disease Control and Prevention. Ms. Barnes and her husband had entered the bat cave with a group, and yet only she became sick. The reason is unknown, but she thought she might have touched guano-soiled rocks and then covered her nose and mouth with her hands because the cave smelled so bad.
It is also unclear why she survived, but Dr. Eileen Farnon, an epidemiologist at the disease centers, said Ms. Barnes was healthy and fit, received excellent care and might have taken in a small dose of the virus. Even though Ms. Barnes took more than a year to recover fully, she had a fairly mild case, as Marburg goes.
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http://www.nytimes.com/2009/12/22/health/22virus.html?_r=1