First human case of rare mosquito-borne disease detected in NH

A resident of Hanover was found with JCV.

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CONCORD, NH – The New Hampshire Department of Health and Human Services (DHHS) has identified the first human case of Jamestown Canyon virus (JCV) of 2017. A New Hampshire resident from Hanover has tested positive for JCV, a virus transmitted by infected mosquitoes.

“Jamestown Canyon Virus is one of several viral infections that can be transmitted through the bite of an infected mosquito in New Hampshire,” said State Epidemiologist Dr. Benjamin Chan. “It is an uncommon infection to be found, but similar to WNV and EEE, it also has the potential to cause serious health complications, including central nervous system infection. Because of the risk for various infections from mosquitoes, we want to remind people to take steps to avoid mosquito bites and remove areas of standing water around their homes where mosquitoes might breed and reproduce.”


⇒ Click here for Jamestown Canyon Virus fact sheet


JCV is a mosquito-borne pathogen that circulates widely in North America, primarily between deer and a variety of mosquito species, but can also infect humans. Since 2000, more than 50 human cases of JCV have been identified nationally. Most infections caused by Jamestown Canyon Virus are either asymptomatic or result in a mild febrile illness, but more serious central nervous system complications, including meningitis and encephalitis, can also occur. There is no specific treatment for JCV, and care is supportive until symptoms resolve.

The best way to prevent infection from JCV and other mosquito-borne illnesses like West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE) is to prevent mosquito bites. Residents and visitors to New Hampshire should protect themselves and their family members by using an effective mosquito repellant that contains 30% DEET, wearing long sleeves and pants at dawn and dusk when mosquitoes are most active, and removing standing water from around your home so mosquitoes do not have a place to breed. Repellents with Picaridin, IR3535 and some oil of lemon eucalyptus and para-menthane-diol products also provide protection against mosquito bites.

Anyone with questions about WNV/EEE can call the New Hampshire Bureau if Infectious Disease Control at603-271-4496. More information is available on the DHHS website at www.dhhs.nh.gov/dphs/cdcs/documents/jamestown-canyon-virus.pdf and on the Centers for Disease Control and Prevention website atwww.cdc.gov.

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NH Department of Health and Human Services