Chikungunya Virus: Questions and Answers
What to Know About the Mosquito-Borne Virus That Has Emerged In the Caribbean
By Kathleen Doheny
Reviewed by Brunilda Nazario, MD
June 17, 2014 -- A crippling mosquito-borne virus with a tongue-twisting name -- Chikungunya -- has spread to the Caribbean, and U.S. travelers have brought it home to at least 10 states.
Here is what you should know about this virus and how to lower your risk of infection, especially if you are traveling to the Caribbean. While the virus remains rare in the U.S., no vaccine is available.
What is Chikungunya virus?
Chikungunya virus is "predominately spread from person to person through mosquitoes," says Kristy Murray, DVM, PhD, an infectious disease specialist in Houston.
It's pronounced "chik-en-gun-ye."
''It's an African word, and it translates to 'that which bends up,'" Murray says, because people bend up with joint pain, one of the most common symptoms.
Where did it come from, and how does it spread?
Scientists believe the virus originated in 1952 in southern Tanzania. Chimpanzees or other animals were probably first infected, says Amesh Adalja, MD, an infectious disease specialist in Pittsburgh.
Mosquitoes who bit these animals became infected, then bit and infected people.
The virus can stay in a person's system for about a week, according to the World Health Organization.
When a mosquito feeds on an infected person, the mosquito can become infected and can bite and infect others.
The Aedes aegypti and Aedes albopictus mosquitoes transmit Chikungunya. They also transmit dengue fever, another disease caused by a virus.
Where has Chikungunya been found?
In the past decades, outbreaks have occurred in Africa, Asia, Europe, and the Indian and Pacific Oceans.
The virus was found for the first time in the Americas on Caribbean islands in late 2013. As of early June, 17 Caribbean countries have reported outbreaks, according to the CDC.
As of June 10, 39 travel-associated cases have been reported in 10 states and the U.S. Virgin Islands, according to the CDC, with an additional case that was locally transmitted in Puerto Rico. Since then, at least three other states -- North Carolina, Indiana, and Tennessee -- have confirmed cases in returning travelers. No transmission between people in the U.S. has been found.
What are the symptoms?
"Usually fever, rash, muscle aches, and joint pain," Adalja says.
Headache and joint swelling can also happen.
"When a person first becomes sick, they will think they have a flu-like illness," Murray says.
Symptoms first appear about 4 to 7 days after the bite, according to the World Health Organization.
A high percentage of those infected become sick, Murray says. She estimates that 90% of those bitten will develop symptoms.
What is the treatment?
How severe is it?
The disease is rarely fatal, according to the World Health Organization, although in older people, the disease can contribute to the cause of death.
As of June 13, 4,576 cases have been confirmed in the Caribbean, with 14 deaths, according to the Pan American Health Organization.
"Most people will get better in about a week," Adalja says, although some will need to be hospitalized. A small number people will have joint pain that lasts for months, he says.
How do you minimize risk?
Travelers to areas where the virus is circulating can take precautions against mosquito bites. The mosquitoes carrying the virus can bite day or night, indoors or out. The CDC advises:
SOURCES: World Health Organization: "Chikungunya." CDC: "Chikungunya in the Caribbean." CDC: "Chikungunya virus." Amesh Adalja, MD, infectious disease specialist, University of Pittsburgh; member, Infectious Diseases Society of America. Kristy Murray, DVM, PhD, infectious disease specialist, Baylor College of Medicine and Texas Children's Hospital. Houston. Indiana State Department of Health. Tennessee Department of Health. North Carolina Department of Health and Human Services.