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We recently reported about the introduction of the Chikungunya (CHIK) virus in the Caribbean. Within two months, confirmed cases have climbed from 98 to well over 8,000 and is threatening to spread to Central and South America. The numbers are continuing to climb and could begin to creep into the Gulf Coast states in the U.S.
The virus is spread via mosquito bite and is often confused with dengue fever. The symptoms include, fatigue, nausea, vomiting, muscle pain, rash and joint pain. Some patients report joint pain lingering for weeks to months feeling similar to arthritis pain.
In early January the list of reported cases was under 100 and included the islands of St. Maarten, St. Barts, Guadalupe and Guyane. However, the infectious disease trackers suspected under-reporting due to confusion with dengue fever, lack of testing and concern over disruption of the tourist season.
James Wilson, M.D. the director of the National Infectious Disease Forecast Center writes that as of February 27th, the virus has spread rapidly into several islands, South American and Central America and infected over 8,000 individuals and there have been three confirmed fatalities.
Dr. Wilson writes,
“True case counts are likely much higher than 8,000 due to under-reporting, lack of test kits, willingness to report, and diagnostic confusion with dengue, among other factors. We consider it impossible that CHIK is not currently in circulation in South America, as indicated above. It is also our strong belief the virus is also in circulation in Central America or southern Mexico, where reporting is confused with dengue. Mention of increased case counts is expected as seasonal ambient temperatures are increasing north of the equator. Spring Break will soon pose a time frame of concern for returning US travelers from the region.
The French Institute for Public Health has reported the following affected areas. The areas affected are Saint Martin, Martinique, Saint Barthélemy, Guadeloupe, Virgin Islands (UK), Sint Maarten, Anguilla, Dominica, Aruba, Saint Kitts and Nevis and French Guiana in mainland South America. In French Guiana, a cluster of autochthonous cases was detected in Kourou bringing the number of cases there to 17.
Will Chikungunya Come to the United States?
Dr. Wilson spoke with us about the possible movement of the virus into the US. He writes, “The threat of introduction of exotic Chikungunya virus to the United States began with a large epidemic that spread from Reunion to southern and southeast Asia. The issue was a higher than usual volume of Chikungunya introduction by air traffic from these areas of the world to the US. These were usually reported as one or two cases at a time in returning travelers.”
“The threat has expanded now, where an introduction to the Caribbean that has spread dramatically, as we anticipated. And now includes indigenous transmission in South America. It is our expectation that transmission is also occurring in Central America and possibly southern Mexico as well, but unrecognized or unreported. We expect such transmission will likely expand northward and represent a much larger risk of introduction and possible establishment in the US Gulf States due to the sheer volume of human trans-border traffic.”
Finally he added, “It is our expectation CHIK will spread northward through Mexico and the Gulf region to affect US Gulf states – if not over the summer then by next summer.”
We want to let physicians and health care practitioners know that this is something to look out for, especially in the Southern states along the Gulf Coast. If you are an M.D. or D.O. we will be discussing this in further detail inside Sermo, please join us.
Note: The map above is approximate and doesn’t include French Guiana on mainland South America.