Update on EEE In MA (8/28/19)

It has been an active summer for Eastern Equine Encephalitis (EEE) in mosquitoes in Massachusetts. DPH and the Massachusetts Department of Agricultural Resources (MDAR), in close consultation with local boards of health, completed a second round of aerial mosquito spraying in parts of Bristol and Plymouth counties and are conducting aerial spraying in parts of Worcester and Middlesex counties this week..

EEE is a rare but serious and potentially fatal disease that can affect people of all ages. The first two human cases of EEE in Massachusetts since 2013 were announced on August 10 and August 16, and, with the recent announcements of the third and fourth human cases, are an indication of the current significant risk of EEE in the Commonwealth.  

We continue to urge all residents, in the spray zone or not, to protect themselves from mosquito bites by staying indoors during peak mosquito hours, applying insect repellent when outdoors, draining standing water where mosquitoes breed, and repairing screens in doors and windows. 

Several resources are available

Updated risk maps may be found here http://www.mosquitoresults.com 

Preventing Mosquito Bites

Why is it important to prevent mosquito bites?

Mosquitoes can spread diseases that make you sick. In Massachusetts, mosquitoes can give you eastern equine encephalitis (EEE) virus and West Nile virus (WNV).

Eastern equine encephalitis (EEE) is a rare but serious disease. Symptoms include high fever, stiff neck, headache, and lack of energy. Swelling of the brain, called encephalitis, is the most dangerous complication, and can cause coma and death. Most cases in Massachusetts occur in the southeastern part of the state.

West Nile virus infections are more common than EEE, but most do not cause any symptoms. Mild WNV infections can cause fever, headache and body aches, often with a skin rash and swollen lymph glands. A small number of people (less than 1 out of 100) who get infected with West Nile virus develop more serious illness; this is more common in people over the age of 50. Symptoms of serious illness include headache, high fever, stiff neck, confusion, muscle weakness, tremors (shaking), convulsions, coma, paralysis swelling of the brain, and sometimes death.

Only a small number of mosquitoes are infected at any given time, so being bitten by a mosquito does not mean you will get sick. However, the best way to avoid both of these illnesses is to prevent mosquito bites.

See your doctor if you develop these symptoms.

What is the best way to prevent mosquito bites?

Use mosquito repellent any time you are outdoors. Even being out a short time can be long enough to get a mosquito bite. Make sure to follow directions on the label.-

Be aware of mosquitoes around you. If mosquitoes are biting you, reapply repellent, or think about going inside.-

Be aware of peak mosquito hours. The hours from dusk to dawn are peak biting times for many species of mosquitoes. Take extra care to use repellent and protective clothing during evening and early morning -- or consider avoiding outdoor activities during these times.

Use mosquito netting on baby carriages or playpens when your baby is outdoors.

When weather permits, wear long-sleeves, long pants and socks when outdoors.

Make sure screens are repaired and are tightly attached to doors and windows.

Remove standing water from places like ditches, gutters, old tires, wheel barrows, and wading pools. Mosquitoes can begin to grow in any puddle or standing water that lasts for more than four days, so don’t let water collect around your home.

Avoid camping overnight near freshwater swamps to reduce your risk of exposure to mosquitoes that carry the EEE virus. If you do go camping, use a tent with mosquito netting and use appropriate repellents.

What kind of mosquito repellent should I use?

Different repellents work against different bugs. It is important to look at the active ingredient on the product label. Repellents that contain DEET, permethrin, picaridin or IR3535 provide protection against mosquitoes. In addition, oil of lemon eucalyptus has been found to provide as much protection as low concentrations of DEET.

DEET products should not be used on infants under 2 months of age. Children older than two months should use products with DEET concentrations of 30% or less. In general, the higher the percentage of DEET, the longer it lasts. Products with DEET concentrations higher than 30% do not provide better protection, but they do last longer. Be sure to read the label to see what the concentration of DEET is, and how often it should be reapplied.

Permethrin products are intended to be used on items such as clothing, shoes, bed nets and camping gear and should not be applied to skin. Apply the permethrin to your clothes before you put them on and follow the instructions on the label.

Additional resources and information

For risk levels, mosquito results, and maps, visit www.mass.gov/dph/mosquito

For updates on aerial spraying, visit www.mass.gov/guides/aerial-mosquito-control-summer-2019.

Mass.gov Mosquito-borne disease information: https://www.mass.gov/lists/mosquito-borne-disease-information-for-the-general-public