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State's Aerial Spraying Operation To Control Mosquitoes Carrying EEE Is On Time And On Schedule

Favorable weather may allow for the completion of pesticide treatment in two of the four areas that state officials have assessed to be at critical risk for the EEE virus and possibly one more zone. Originating at Quonset State Airport, the first flight took off shortly after 7 PM. The operation to spray parts of Westerly, Hopkinton, and Charlestown is scheduled for Monday night, weather permitting.

PROVIDENCE The Department of Environmental Management (DEM) and the Rhode Island Department of Health (RIDOH) tonight announced that the operation to disperse aerial mosquito treatments in four areas that state officials have assessed to be at critical risk for the Eastern Equine Encephalitis (EEE) virus started on time and is on schedule.

As of 10:30 PM, the state can confirm that the crew piloting a fixed-wing, King Air Beechcraft plane has treated an area including all West Warwick and parts of Coventry, Cranston, Warwick, East Greenwich, and West Greenwich. At this time, it also is looking increasingly likely that calm, mild weather will allow the crew to complete treatment in a highly populated zone including all Central Falls, Pawtucket, and North Providence and parts of Providence, East Providence, Smithfield, Lincoln, and Cumberland.

Provided that the temperature stays above 58 degrees, the operation will continue into the overnight hours tonight with the crew also trying to complete spraying an area in northern Rhode Island including parts of Burrillville, North Smithfield, and Woonsocket. If spraying cannot be completed in this northern tier early tomorrow morning, the crew will finish spraying in these communities tomorrow night. Also tomorrow night, the aerial spraying operation will resume for a zone in southern Rhode Island including parts of Westerly, Hopkinton, and Charlestown.

The determination of critical risk was made based on results of mosquito samples in Rhode Island, Massachusetts, and Connecticut; and cases of EEE in mammals in Rhode Island. There has been one human case of EEE in Rhode Island this year and one horse has tested positive. EEE is a rare but serious and potentially fatal disease that can affect people of all ages. RIDOH confirmed the state's first human case of EEE in a person over the age of 50 from West Warwick on August 30. Two mosquito detections of EEE have occurred in Central Falls and two have occurred in Westerly. The state's transmission in a horse, announced August 29 by DEM, also originated in Westerly.

The pesticide that is being applied, Anvil 10+10, is being used at very low concentrations. Spraying is only being done during calm periods, with winds less than 10 MPH. This helps prevent the pesticide from drifting beyond targeted areas. Spraying will not occur over fish hatcheries, certified organic farms, surface drinking water supplies, and other open water bodies and coastal areas. Massachusetts officials used the same product in recent aerial spraying in Bristol, Plymouth, Worcester, and other counties. Anvil is registered by the US Environmental Protection Agency (EPA) and in Rhode Island and Massachusetts for this use. The purpose of this application of pesticide is to kill adult mosquitoes as they are flying around in the air. Because mosquitoes are cold-blooded and cannot regulate their internal temperatures, anything colder than 58 degrees will cause adult mosquitoes to hunker down, limiting the effectiveness of the spraying.

While spraying is occurring, it is best to err on the side of caution and limit time outdoors and keep your windows closed. The product being sprayed is being used at very low concentrations. No adverse health risks are expected with its use for mosquito control. However, it is generally good for people to limit their exposure to pesticides.

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  • Department or agency: Department of Environmental Management
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  • Release date: 09-08-2019

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