Disease still mystery for U.S. researchers

NEW YORK — A century ago, B.E. Dahlgren created a monster for the American Museum of Natural History.

It was based on a real-life killer that claims more human lives each year than any other creature in the animal kingdom: the mosquito.

On Thursday, nearly 100 years later, it was pulled out of storage, dusted off and put on display. The mosquito — the Aedes aegypti — is again causing trouble.

This particular mosquito is the main carrier of the Zika virus. It has spread the disease throughout South America and into the Caribbean. The virus is likely to reach Florida and the Gulf States this summer.

Museum officials gathered a panel of experts on Thursday night to try to answer some of the most frightening and difficult questions about the risks Zika poses and what can be done to mitigate the danger. The panel included Dr. Jay Varma, deputy commissioner for disease control at the New York City Department of Health; Dr. Catherine Spong, acting director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development; and Dr. W. Ian Lipkin, the director of the Center for Infection and Immunity at the Columbia University Mailman School of Public Health.

If ever a group could answer questions about a complicated public health threat, this would be it. However, there was a common refrain over the course of the evening: We don’t really know yet.

What they do know: “If you are a woman who is pregnant, you really shouldn’t be going south,” Varma said, bluntly.

While Zika generally causes no symptoms in most healthy adults, it can do great harm to a developing fetus, sometimes causing microcephaly, a condition in which babies have unusually small heads and damage to the brain.

Most people whohave no symptoms and have shown a negative on all the tests can be relatively sure they are in the clear. False positives, however, are possible because Zika is a flavivirus; a positive test result can be triggered by one of the related viruses.

All this makes Spong’s job incredibly difficult. In addition to her research role, she also treats patients. She said she often is unable to provide precise advice to pregnant women about the risks they face. There is no treatment for pregnant women who have tested positive for Zika.

Perhaps just as troubling, she said, was that some of the women were infected as late as their third trimester, when the fetus had already developed to a large degree.

“I don’t have a lot of information about how to quantify these risks,” she said.