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The next mosquito-borne infection you might want to start worrying about

An Aedes aegypti mosquito (Agriculture Department via AP)

It's called chikungunya virus, and it's already here in the United States, with 28 cases brought into parts of the country by travelers from 17 countries, mainly in the Caribbean, where more than 103,000 people have been afflicted by the debilitating virus, the Centers for Disease Control and Prevention reported Thursday.

Similar in some ways to dengue fever, the virus, (pronounced chik-en-gun-ye) causes high fever and intense pain and swelling in joints, as well as muscle pain and headaches. It is transmitted by two kinds of mosquitoes found in parts of the United States. The disease is rarely fatal, but there is no treatment other than pain relief. And while the virus tends to run its course in a week or so, pain can linger for months and, in some cases, years.

So far, there have been no documented cases of transmission from one person to another via mosquito in the United States, the CDC reported, (all the cases have been imported by travelers), but one researcher believes it's only a matter of time. "There is a high risk that there will eventually be some transmission in Florida," said Scott Weaver, director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch in Galveston.

Weaver and others, including the National Institutes of Health, are working on vaccines for the disease, which originated in Africa and has erupted in parts of the globe for centuries. The latest version arrived in the Caribbean last fall and has spread rapidly, Weaver said.

The two mosquitoes that carry the virus, Aedes aegypti and Aedes albopictus, are aggressive and bite during the day, Weaver said, meaning that people must protect themselves differently than they would against night-biting mosquitoes that carry an infection such as West Nile. While that means staying vigilant against mosquitoes during the day as well as the evening, he said, residents of the United States also have two distinct advantages over people in the Caribbean and Latin America.

First, because use of air conditioning and window screens is widespread in this country, many fewer mosquitoes enter homes in the United States than in the Caribbean, where windows are generally left open and unscreened to cool houses. And except in South Florida and parts of the Gulf Coast, Weaver said, the mosquitoes that carry the virus probably do not survive in large enough numbers each winter to continue a transmission cycle.

But "if you're a traveler, especially to the Caribbean or Southeast Asia, what people need to understand is … that this is not the same kind of risk as something like West Nile," he said.