Aerial spraying expanded to 21 southeastern Massachusetts communities to combat EEE

By Kay Lazar, Globe Staff

One day after public health officials announced they will spray a wide swath of southeastern Massachusetts with pesticides to combat disease-carrying mosquitoes, more infected insects have been found, prompting a decision to substantially widen the targeted area to nearly two dozen communities.

Aerial spraying is slated to begin Friday evening and continue Saturday night to prevent the spread of eastern equine encephalitis to people in 21 cities and towns.

Mosquitoes infected with EEE were found in Rehoboth, prompting officials to urge residents there to avoid nighttime activities, when the insects are most active. The state Department of Public Health said the EEE threat level has been raised to “high” in Rehoboth and to “moderate” in neighboring Attleboro, Seekonk, and Swansea.

Here is the announcement from state health officials:

The Massachusetts Department of Public Health (DPH) today announced that an additional ten communities in southeastern Massachusetts will receive aerial spraying of pesticides against mosquitoes, bringing the total number of communities in the spraying zone to 21. Spraying is scheduled to begin on the evening of Friday, July 20 after dark, and will continue on the evening of Saturday, July 21, weather permitting.

The list of communities that will be sprayed include: Acushnet, Berkley, Bridgewater, Carver, Dighton, East Bridgewater, Easton, Freetown, Halifax, Hanson, Kingston, Lakeville, Middleborough, Norton, Pembroke, Plympton, Raynham, Rehoboth, Rochester, Taunton, and West Bridgewater. Residents are encouraged to check the DPH website at www.mass.gov/dph for updates.

In addition, DPH officials today announced the detection of two EEE-positive mammal-biting mosquito pools in the town of Rehoboth. As a result, the EEE threat level has been raised to “high” in Rehoboth and to “moderate” in the neighboring towns of Attleboro, Seekonk, and Swansea. In recognition of its high risk designation, residents in Rehoboth are urged to curtail nighttime activities to avoid mosquitoes when they’re at their most active.

“As we continue planning for aerial spraying in these cities and towns, we strongly encourage residents to remember that personal protective measures are the first line of defense against mosquitoes,” said DPH Commissioner John Auerbach. “Use insect repellant with DEET, cover exposed skin when outdoors, and take steps to prevent mosquitoes in and around your home.”

Health officials will continue to conduct enhanced mosquito sampling in the coming days and have already increased ground spraying activities. Residents are encouraged to continue checking local media and the DPH website at www.mass.gov/dph for further details and updates.

There have been no human cases of West Nile virus (WNV) or EEE so far this year. There were two cases of EEE in August of last year acquired in Massachusetts; a fatal case in a Bristol County man and an infection in a tourist from out of state. EEE activity in both 2010 and 2011 raised public concern and prompted DPH to work with a panel of experts to evaluate and enhance the state’s surveillance and response program. EEE is spread to humans through the bite of an infected mosquito. EEE is a serious disease in all ages and can even cause death.

People have an important role to play in protecting themselves and their loved ones from illnesses caused by mosquitoes.

Avoid Mosquito Bites

Apply Insect Repellent when Outdoors. Use a repellent with DEET (N, N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023), oil of lemon eucalyptus [p-methane 3, 8-diol (PMD)] or IR3535 according to the instructions on the product label. DEET products should not be used on infants under two months of age and should be used in concentrations of 30% or less on older children. Oil of lemon eucalyptus should not be used on children under three years of age.

Be Aware of Peak Mosquito Hours. The hours from dusk to dawn are peak biting times for many mosquitoes. Consider rescheduling outdoor activities that occur during evening or early morning.

Clothing Can Help Reduce Mosquito Bites. Wearing long-sleeves, long pants and socks when outdoors will help keep mosquitoes away from your skin.

Mosquito-Proof Your Home

Drain Standing Water. Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to breed by either draining or discarding items that hold water. Check rain gutters and drains. Empty any unused flowerpots and wading pools, and change water in birdbaths frequently.

Install or Repair Screens. Keep mosquitoes outside by having tightly-fitting screens on all of your windows and doors.

Protect Your Animals

Animal owners should reduce potential mosquito breeding sites on their property by eliminating standing water from containers such as buckets, tires, and wading pools – especially after heavy rains. Water troughs provide excellent mosquito breeding habitats and should be flushed out at least once a week during the summer months to reduce mosquitoes near paddock areas. Horse owners should keep horses in indoor stalls at night to reduce their risk of exposure to mosquitoes. If an animal is diagnosed with WNV or EEE, owners are required to report to DAR, Division of Animal Health by calling 617-626-1795 and to the Department of Public Health (DPH) by calling 617-983-6800.

More information, including all WNV and EEE positive results from 2012, can be found on the Arbovirus Surveillance Information web page at www.mass.gov/dph/wnv or by calling the DPH Epidemiology Program at 617-983-6800. The findings of the DPH Eastern Equine Encephalitis Expert Panel can be found here.