Chikungunya coming to the US? What you need to know about the virus

Numerous Chikungunya virus particles, which are composed of a central dense core that is surrounded by a viral envelope. (CDC.gov)

The chikungunya virus, a mosquito-borne illness that causes high fevers and sometimes intense pain, is spreading rapidly throughout the Caribbean.

Now, numerous cases of the disease have appeared in the United States – including 25 in Florida – from travelers who contracted the disease while out of the country, according to the Centers for Disease Control and Prevention (CDC). And experts say it's only a matter of time before it begins spreading among local mosquitos within the U.S.

First identified in Tanzania in 1952, chikungunya has mostly remained within Sub-Saharan Africa, the Arabian Peninsula and Southeast Asia for the past few decades – despite occasional cases appearing in the United States from a returning traveler.

But it all changed in 2013, when health experts found that sustained transmission of the chikungunya virus had occurred in the Caribbean, meaning people on the islands were starting to become infected by local mosquitos.  Now the virus is widespread, with up to 17 different countries in the Caribbean reporting cases of the disease.

Given the amount of U.S. travelers who vacation on these tropical islands each year, health experts believe chikungunya will soon spread beyond the Caribbean Sea, setting up shop in its neighboring continents.

“The mosquitos that transmit this infection are pretty widespread around the world, and that’s why the infection has been able to spread across the tropical Pacific and now into the Caribbean,” Dr. Jorge Parada, medical director of the infection prevention program at Loyola University, Chicago, and medical spokesperson for the National Pest Management Association, told FoxNews.com.  “And there’s absolutely no reason why this infection can’t spread to more of South America and the southern United States.”

Parada noted that chikungunya’s spread likely reflects the increased mobility of people today, as well as the changing climate, which has caused many plants, animals and insects to adjust the ranges of their habitats to accommodate the warmer weather.

Given chikungunya’s inevitable crossover to America, here’s what you need to know about the virus – and how you can protect yourself from infection.

What is chikungunya?

Chikungunya is a viral infection transmitted to humans by infected mosquitos – mainly by the Aedes aegypti and Aedes albopictus species.  According to Parada, these types of mosquitos are widespread across the Americas and tend to bite during the daytime rather than at night.  Unlike other mosquitos that spread disease, such as the ones responsible for malaria, these mosquitos are found in urban areas and can thrive in big cities.

Infection of the chikungunya virus occurs when a person gets bitten by a mosquito that has previously fed on another infected individual.

“[If you] have the virus circulating in your bloodstream, the mosquito sucks your blood, acquires the virus, and if it feeds again, there’s always some level of regurgitation of the prior meal,” Parada said. “Then they inoculate us with the virus, so we can then get infected.”

Once a person becomes infected, there’s an incubation period of three to seven days before symptoms present.  The most common signs of the virus are fever and joint pain, typically in multiple different joints.  Like any viral syndrome, chikungunya can also cause muscle aches, headaches, rash and joint swelling.

Although rarely lethal, there is no cure for chikungunya, and its effects can be quite debilitating – especially for the elderly population.  While some patients will only suffer a minor fever and mild joint pain that dissipates within a week, others can suffer very high fevers and sustained joint pain for several weeks or even months.

In fact, in the Makonde language, the term “chikungunya” means to be bent out of shape, in reference to the virus’s ability to cause people to contort in pain.

“The key thing is it tends to give you a lot of joint pain,” Parada said.  “There’s a saying that, ‘It won’t kill you, but you may wish you're dead.’”

How to stop infection

Since there aren’t any current therapies for treating chikungunya, Parada said the best course of action is prevention – mainly by avoiding mosquito bites.  Fortunately, the United States has much better mosquito control than many other nations, as most Americans live in air conditioned homes with screens and filters.

But on an individual level, people can reduce their exposure to mosquitos by wearing protective clothing, utilizing insect repellents and staying indoors on hot days.  Additionally, people should avoid or eliminate any standing water near their home, as it can serve as a mosquito breeding site.  Parada said homeowners should also make sure leaves don’t pile up in their gutters, as this can cause water to pool.

If someone does become infected with chikungunya, he or she should go to a doctor and try to wait out the symptoms.  Over-the-counter pain medications can help to mitigate the severity of the aches, but there’s no treatment for eliminating the virus.  Furthermore, infected patients can help to stop the spread of the disease by taking extra precautions to avoid mosquitos.

“That person should really make an effort not to get mosquito bites,” Parada said. “You don’t want that person acting as a source of infection for more people.  I can imagine people thinking the opposite: ‘I already got it. What does it matter?’ But they really don’t want to get bitten by mosquitos and pass it along.”

So far, there have only been a few isolated cases of chikungunya in the United States, and there have been no reports of sustained transmission, so people don’t need to worry just yet. And even when the virus does travel over to the United States, Parada said there’s no reason to panic.

“The bad news is: It is a not fun infection. But the good news is you’re not going to die from it,” Parada said.  “Many people would say this is more uncomfortable than catching the flu, but unlike the flu, this won’t kill you.  So you have to take it in that context.”

For more information on the spread of chikungunya in the Caribbean, visit the CDC's website.