The New Hampshire Department of Health and Human Services (DHHS) is announcing the first human case of Eastern Equine Encephalitis (EEE) this season in an adult from Conway. The most recent previous human case of EEE in New Hampshire was confirmed in 2009.


Eastern equine encephalitis virus (EEEV) cycle/CDC

Also four additional mosquito batches were found to be positive in New Hampshire today; two in Derry and two in Candia. Three of these batches were bird biting mosquitoes indicating an increase in EEE activity in the bird population. One of the batches was a mammal biting species which increases the risk of additional human or veterinary cases of EEE.  This brings the total of EEE mosquito batches identified this season to five. There have been no West Nile Virus positives yet this year. 

In 2013, there were 27 positives for EEE, including 24 mosquito batches and 3 animals. EEE and WNV are transmitted by the bite of infected mosquitos. This human finding will change the arboviral risk map for Conway to high and the surrounding municipalities of Chatham, Bartlett, Hales Location, Albany, Madison, and Eaton to moderate. The risk level in Derry will remain at moderate. The risk level for Candia will increase to moderate.

“This positive is at about the same time as the previous EEE patient identified in 2009,” said NH Public Health Director Dr. José Montero. “There is no way to know where exactly this individual was infected, but we do know that both of these diseases are present in New Hampshire so it is important that everyone remember to take steps to prevent mosquito bites to themselves and their loved ones.”

Symptoms of EEE disease often appear 4 to 10 days after being bitten. If you or someone you know is experiencing flu-like symptoms, including fever and headache, contact your local medical provider. EEE is a more serious disease than WNV and carries a high mortality rate for those who contract the serious encephalitis form of the illness. Symptoms may include high fever, severe headache, stiff neck, and sore throat. There is no specific treatment for the disease, which can lead to seizures and coma.

You can protect yourself and your family from WNV and EEE with a few simple steps, such as using effective mosquito repellent, wearing long sleeves and pants at dawn and dusk when mosquitoes are most active, removing standing water from around your house so mosquitoes do not have a place to breed, and by checking doors and windows to ensure screens are in place and in good condition to prevent mosquitoes from entering your home.