Earlier this month, the Mississippi State Department of Health (MSDH) reported the first-ever confirmed case of the mosquito-borne virus chikungunya (chik-en-gun-ye) in the state of Mississippi.
Chikungunya produces similar symptoms to the mosquito-borne West Nile virus, and like West Nile can be fatal. So, is Mississippi facing another West Nile-like epidemic threat?
MSDH says “no” — at least not yet.
“To the best of our knowledge, there are no mosquitoes in Mississippi carrying the chikungunya virus,” said Dr. Paul Byers, deputy state epidemiologist with MSDH.
The infected Mississippian is believed to have contracted the disease while on a trip to Haiti. Historically found only in Africa and Asia, just last December health authorities identified for the first time in the Americas the transmission of chikungunya in the Caribbean. Cases have also been identified in other Southeastern states (Florida and Georgia), and according to the Centers for Disease Control (CDC) the illness’ numbers are on the rise across the nation (80 cases as of June 17).
However, MSDH is quick to emphasize that Mississippi is not home to the variety of mosquitoes that carry the chikungunya virus. The only way the disease could spread in Mississippi is if an infected individual were to be bitten by a non-chikungunya-infected mosquito that could, in turn, transmit it to other people.
The key to checking chikungunya’s advance in Mississippi is quarantining patients.
“Chikungunya virus is spread from person to person through the bite of the Aedes mosquito,” said State Epidemiologist Dr. Thomas Dobbs. Dobbs said people who think they might be infected with the virus should see their health care provider and stay indoors while sick.
“Mississippi residents who are sick with chikungunya should stay indoors for at least 10 days and avoid mosquito bites, as native Mississippi mosquitoes could pick up the virus and spread it to other people,” he added.
Health officials believe the infected Mississippian was identified in time, and the patient’s quarantine should have checked any chance of the disease spreading here, at least for now.
Byers said MSDH is not surprised by Mississippi’s first case of chikungunya. He said the agency was expecting some cases to arise from people vacationing this summer in the Caribbean after monitoring CDC reports on the outbreak there.
The main concern is that Mississippians travelling to the Caribbean this summer will be unaware of the disease, not protect themselves from it and spread it to others back home, Byers said.
Chikungunya has historically been a health concern for lands far from Mississippi. Outbreaks have occurred in Africa and Asia as well as Europe and the Indian and Pacific oceans.
However, it is spreading, and the late 2013 discovery of chikungunya virus in the Caribbean has ramped up concerns here. The CDC reports the chikungunya virus is not currently found anywhere in the United States, but, again, there is a risk that the virus will be imported to new areas by infected travelers.
There is no vaccine to prevent or medicine to treat chikungunya virus infection. Symptoms usually begin three to seven days after being bitten by an infected mosquito. The most common symptoms are fever and joint pain. Other symptoms are headache, muscle pain, joint swelling and/or rash. Most patients feel better within a week; however, in some people the joint pain may persist for months. People at risk for more severe disease include newborns infected around the time of birth, older adults (65 years and older) and people with medical conditions such as high blood pressure, diabetes or heart disease.
Many of these symptoms are similar to West Nile, but Byers said there are some important differences. Whereas only about 20 percent of West Nile patients exhibit symptoms of the disease, approximately 80 percent of those infected become sick from chikungunya.
The good news is chikungunya is far less likely to result in death. The CDC reports that the case-mortality rate of West Nile patients in 2012 and 2013 was approximately five out of 100. Conversely, the mortality rate among chikungunya patients is roughly one in 1,000.
The CDC and MSDH recommend similar protections from chikungunya as it does for West Nile. They are: Use a recommended mosquito repellent that contains DEET while outdoors; remove all sources of standing water around homes and yards to prevent mosquito breeding; wear loose, light-colored, long clothing to cover the arms and legs when outdoors; and avoid areas where mosquitoes are prevalent (mosquitoes that carry chikungunya virus are especially active during the day.
Travelers to the Caribbean are encouraged to visit www.HealthyMS.com/chik for more information.