CHIK-V now in 47 US States

Physicians treating patients with fever, aching joints, and other viral symptoms might want to ask about patients’ travel history. If they have been to the Caribbean, they could have Chikungunya virus, known also as CHIK-V.

CHIK-V infection has now been reported in every state in the US except Wyoming, Montana, and North Dakota, a national 12-month total of 2,333 cases as of January, 2015 according to the US Centers for Disease Control and Prevention (CDC). That represents a sharp spike over prior years when about 68 US cases were reported annually. The mosquito-borne virus has been endemic in the Caribbean and other regions with year-round hot climates for many years, and has taken root in Florida. There have been 11 locally transmitted cases reported there in the past year.

The rest of the US cases have been travel-related, but the CDC warns that “imported cases could result in local spread of the virus in the continental US.”

Disease symptoms are much like those of Dengue fever. The illness can be fatal and can cause long-term debilitating joint pain. But unlike Dengue, CHIK-V infection confers immunity on those who have had it.

CHIK-V is not a nationally notifiable disease, but the cases have been reported voluntarily to ArboNET, the national surveillance system for arthropod-borne diseases. Since reporting is not mandatory, and cases are also likely to go undiagnosed in the US, the actual numbers are likely higher.

The highest number of cases (688) is in NY, likely because New York City has a large population of people who travel regularly to the Caribbean. There were 4,168 cases of CHIK-V in Puerto Rico last year. The island’s public health officials launched a door-to-door campaign urging residents to use insect repellants and to try to keep mosquitos out of their homes.

CHIK-V made tabloid news in January when actress Lindsay Lohan tweeted that she had come down with a case while on vacation.