Rare Mosquito-Borne Jamestown Canyon Virus Detected in New Hampshire

Aug 18, 2017

A person in Hanover has tested positive for a rare mosquito-borne illness called the Jamestown Canyon Virus, but health officials are stressing this is a sign to take precautions against arboviral illnesses of all kinds.

It’s only the third human case of the virus in recent years, according to the state: Others were confirmed in 2013 and 2015. But the disease does show up elsewhere, according to New Hampshire health officials, with more than 50 cases identified across the country since 2000. 

State Epidemiologist Dr. Benjamin Chan says symptoms similar to other mosquito-borne illnesses like West Nile Virus. Many people do not develop any symptoms, he said, but those who do can see anything from mild flu-like illness to a more severe central nervous system infection, like meningitis or brain swelling.

“Jamestown Canyon Virus is one of several different mosquito-borne diseases that people can get in New Hampshire,” Chan sais. “So while it is more uncommon than some of the other steps we’ve talked about, the steps to prevent are the same.”

Those steps, Chan said, include wearing protective clothing, especially around dawn and dusk, and getting rid of any standing water where mosquitoes are likely to breed.

To date this year, only one other person has tested positive for an arboviral illness — someone in Dover reportedly contracted "Powassan Virus" earlier this summer, according to the state's Bureau of Infectious Disease Control. That virus is spread primarily by infected ticks, according to the Centers for Disease Control and Prevention

More information on mosquito-borne illnesses and how to prevent them can be found here