Announcing the U.S. Arrival of Chikungunya Virus

By Mary-Louise Scully, MD

Dr. Mary-Louise Scully is an Infectious Disease Specialist and is the Director of the Sansum Clinic Travel and Tropical Medicine Center.

Summer is here and it’s time for travel. Although many of us won’t be traveling to distant, exotic locations there are still some important travel tips for the United States. A hot topic right now is the arrival of Chikungunya virus (pronounced chik-en-gun-ye). Chikungunya virus derives its name from an east African dialect that roughly translates as “that which contorts or bends up” to represent the achy muscles and joints associated with the fever and flu-like syndrome. And although you usually don’t die – you just feel like you might for several days – some patients can experience debilitating joint pains that can persist for months.

The Aedes mosquito, which is a daytime biter, transmits Chikungunya virus, and this mosquito also is present throughout the United States raising concern about the possible further local spread of the disease. In December 2013, the first cases in the western hemisphere occurred in Saint Martin and now over 189,000 suspected and confirmed cases have been reported in 19 other Caribbean countries. As of June 24, 2014 the CDC has reported 72 cases in U.S. citizens associated with Caribbean travel. The predominant countries where travelers acquired the disease were Haiti, Dominican Republic, Martinique, and Saint Martin. Like Dengue fever virus, which is an increasing global threat, we have no vaccine or pill to prevent Chikungunya virus. In addition, there is no specific anti-viral treatment – only supportive measures such as rest, hydration, and use of Tylenol or anti-inflammatory medications such as ibuprofen, for relief of symptoms.

Personal protection measures and proper use of repellent is therefore the key to prevention. Covering exposed skin and use of clothing treated with permethrin can help. For repellent, the CDC recommends either a DEET- based product, 25-35% (no need for 100%, might melt your cellphone!), or products with 20% Picaridin or IR3535. Beware many products labeled as “natural” are actually not. Repellents containing a synthesized version of oil of lemon eucalyptus (not the “pure” oil of lemon eucalyptus), do seem to have activity against the Culex mosquito, the vector of West Nile virus (WNV). WNV is still a problem, though not getting much media attention these days. However, in 2013 there were 2,469 U.S. cases of WNV reported and the largest number of those cases were from California (237). Evening mosquito protection is needed for WNV, as opposed to daytime insect precautions for Dengue and Chikungunya.

So what to do? I have a saying “If you don’t get bit – you don’t get sick,” easier said than done sometimes. But maybe make some room in your carry-on for a bit of bug repellent. And also remember, accidents and cardiovascular disease still account for the majority of illness and death associated with travel. SoSo, remember— -don’t drink and drive, buckle up that seat belt, and wear a helmet if using a bicycle or motor scooter.

Bon voyage!

Read more about Dr. Scully:
"From West Pueblo to Southern Chad" - Dr. Scully's work for the Chad Relief Foundation
Travel Physician