EEE: Know the Facts

Eastern equine encephalitis (EEE) is a virus spread through mosquito bites. Signs of EEE include flu-like symptoms, such as fever, muscle aches and headaches. This virus infection can progress to cause inflammation of the brain and result in severe neurologic damage and, sometimes, death. Children and adolescents under age 15 are at particular risk.

Infectious disease experts from Massachusetts General Hospital say while EEE is rarely transmitted to people, the risk for human infection usually peaks during the months of August and September.

“We’re really not in the clear until those first hard frosts settle in over New England,” says Edward Ryan, MD, director of Mass General Global Infectious Diseases. “EEE is a virus that is usually transmitted among mosquitoes and non-human animals such as birds. But when a person is infected, it can be severe.”

Along with aerial spraying for mosquitoes, Ryan offers the following tips:

• Avoid outdoor activity from dusk until dawn
• Wear long sleeves to cover exposed skin whenever possible. Products containing permethrin can be used on items such as clothing, shoes, bed nets and camping gear to ward off insects but should not be applied directly to skin
• Wear insect repellents that contain the chemical DEET and are approved by the Centers for Disease Control and Environmental Protection Agency. Repellents can be used on children but should not be used on infants under 2 months of age
• Repellents containing picaridin, R3535 or oil of lemon eucalyptus can be used, but the label instructions should be closely followed. The oil extract should not be used on children under 3 years of age
• Remove standing water from places where mosquitos may breed, such as in children’s water toys, bird baths and pool covers and other open outdoor containers such as buckets, rimless tires and other open containers

The Massachusetts Health Department website also posts the latest information about confirmed EEE cases and mosquito spraying, and offers prevention tips. Ryan recommends staying up to date on potential EEE activity in your community.

“There is no vaccine for EEE and no treatment,” says Ryan. “So it’s vital to minimize the likelihood of getting bitten by a mosquito.”