Mosquito-borne virus chikungunya worries CDC

Brian King6/13/14

By Val Willingham, CNN


CNN) -- A debilitating, mosquito-borne virus called chikungunya has made its way to North Carolina, health officials say. It's the state's first reported case of the virus.

The patient was likely infected in the Caribbean, according to theForsyth County Department of Public Health. Chikungunya is primarily found in Africa, East Asia and the Caribbean islands, but the Centers for Disease Control and Prevention has been watching the virus,+ for fear that it could take hold in the United States -- much like West Nile did more than a decade ago.

The virus, which can cause joint pain and arthritis-like symptoms, has been on the U.S. public health radar for some time. About 25 to 28 infected travelers bring it to the United States each year, said Roger Nasci, chief of the CDC's Arboviral Disease Branch in the Division of Vector-Borne Diseases.

"We haven't had any locally transmitted cases in the U.S. thus far," Nasci said.

But a major outbreak in the Caribbean this year -- with more than 100,000 cases reported -- has health officials concerned. Experts say American tourists are bringing chikungunya back home, and it's just a matter of time before it starts to spread within the United States.

After all, the Caribbean is a popular one with American tourists, and summer is fast approaching.

"So far this year we've recorded eight travel-associated cases, and seven of them have come from countries in the Caribbean where we know the virus is being transmitted," Nasci said.

Other states have also reported cases of chikungunya. The Tennessee Department of Health said the state has had multiple cases of the virus in people who have traveled to the Caribbean.

The virus is not deadly, but it can be painful, with symptoms lasting for weeks. Those with weak immune systems, such as the elderly, are more likely to suffer from the virus' side effects than those who are healthier.

The good news, said Dr. William Shaffner, an infectious disease expert with Vanderbilt University in Nashville, is that the United States is more sophisticated when it comes to controlling mosquitoes than many other nations.

"We live in a largely air-conditioned environment, and we have a lot of screening (window screens, porch screens)," Shaffner said. "So we can separate the humans from the mosquito population, but we cannot be completely be isolated."

Chikungunya was originally identified in East Africa in the 1950s. The ecological makeup of the United States supports the spread of an illness such as this, especially in the tropical areas of Florida and other Southern states, according to the CDC.

The other concern is the type of mosquito that carries the illness. Unlike most mosquitoes that breed and prosper outside from dusk to dawn, the chikungunya virus is most often spread to people by Aedes aegypti and Aedes albopictus mosquitoes.

These are the same mosquitoes that transmit the virus that causes dengue fever. They bite mostly during the daytime. The disease is transmitted from mosquito to human, human to mosquito and so forth. A female mosquito of this type lives three to four weeks and can bite someone every three to four days.

Shaffner and other health experts recommend people remember the mosquito-control basics:

• Use bug spray if you are going out, especially in tropical, or wooded areas near water.

• Get rid of standing water, empty plastic pools, flower pots and pet dishes, so mosquitoes don't breed.

• Dress appropriately, with long sleeves and pants.