Press Releases


Mosquito Spraying Planned For Final Area Of Critical Risk For EEE

With data from the latest round of trapping and testing, State confirms 5th positive finding of EEE and 2nd West Nile Virus detection. Both detections originated at Chapman Swamp in Westerly, which will be sprayed tonight along with parts of Hopkinton and Charlestown. Fog postponed the spraying that was planned in that area last night.

PROVIDENCE The Department of Environmental Management (DEM) and the Rhode Island Department of Health (RIDOH) today announced that, weather permitting, a third application of aerial mosquito treatments will be conducted tonight in parts of Westerly, Hopkinton, and Charlestown. These towns were scheduled to be sprayed late last night but thick ground fog moved into the area, forcing a postponement of this leg of the operation. Earlier last night, however, weather conditions were ideal to complete the dispersal of pesticide in parts of Woonsocket, North Smithfield, and Burrillville. On Sunday night and early Monday morning, spraying was done in all West Warwick and parts of Coventry, Scituate, Cranston, Warwick, East Greenwich, and West Greenwich; as well as all Central Falls, Pawtucket, and North Providence and parts of Providence, East Providence, Smithfield, Lincoln, and Cumberland. (See updated spray map, attached.)

Aerial spraying depends on calm conditions and temperatures above 58 degrees. DEM will provide more details both before and after the flight departs Quonset State Airport at around 7 PM.

As Rhode Island nears completion of aerial spraying to kill adult mosquitoes in four areas that state officials have assessed to be at critical risk for the EEE virus, the Commonwealth of Massachusetts today announced additional aerial spraying in the 78 communities that it has assessed to be at critical and high risk for the disease.

EEE is a rare but serious illness that spreads when people are bitten by infected mosquitoes. Yesterday, RIDOH announced that the individual who had contracted the state's first human case of EEE this year passed away on September 8. This was Rhode Island's first fatal human EEE case since 2007.

In the latest round of trapping, DEM collected 116 pools, or samples, from 28 traps on September 3. The mosquitoes testing positive for both EEE and West Nile Virus (WNV) came from the same pool trapped in Chapman Swamp in Westerly. Statewide to date, EEE has been detected in five mosquito pools two in Central Falls and three in Westerly and WNV has been detected in Tiverton and Westerly. On August 29, DEM also confirmed EEE in a horse in Westerly. Mosquitoes carrying the EEE virus have previously been found in Chapman Swamp in 1996, 2003, 2013, and 2016.

In addition, a deer in Coventry has tested positive for EEE. With deer season opening September 15, DEM will be conducting outreach to hunters to advise on personal precautions when field dressing animals. EEE is not considered to be a threat to the state's deer populations. Deer, like horses, cannot transmit EEE to humans. The transmission of EEE to deer reinforces that 2019 is a higher-than-average risk year for mosquito-borne disease.

In addition, several EEE cases and positive mosquitoes have been detected in Connecticut and Massachusetts, some in areas that border Rhode Island. Generally, spraying in Rhode Island is occurring in four-mile radiuses around positive samples and cases. Results from additional pools collected September 3 and September 5 are pending. RIDOH's State Health Laboratories is continuing to expedite mosquito testing. The Rhode Island Emergency Management Agency continues to coordinate communications between state government and the state's 39 cities and towns.

"Smart scheduling" for communities

Previous mosquito prevention recommendations from RIDOH still are in effect. On Monday of last week, RIDOH recommended to schools and municipal leaders that games, practices, and other outdoor activities scheduled to occur during early morning or dusk hours be rescheduled to earlier in the afternoon or relocated to an indoor venue. The "smart scheduling" of events is intended to help minimize the risk of mosquito bites for players, coaches, and spectators. RIDOH recommends that smart scheduling stay in effect for the remainder of the mosquito season, which typically ends in mid-October (after the first hard frost).

In addition to following this smart scheduling recommendation, there are other measures that Rhode Islanders should take to protect themselves from mosquito bites, and to help minimize mosquito breeding.

Protect yourself

o Put screens on windows and doors. Fix screens that are loose or have holes. o At sunrise and sundown (when mosquitoes that carry EEE and WNV are most active), consider rescheduling outdoor activities that occur during evening or early morning. If you must be outside, wear long-sleeved shirts and long pants and use bug spray. o Use EPA-approved bug spray with one of the following active ingredients: DEET (20-30% strength); picaridin, IR3535; and oil of lemon eucalyptus or paramenthane. Always read the label and follow all directions and precautions. o If you plan to hike in the woods in daylight, it is advisable to wear repellent to prevent being bitten by daytime mosquitoes. o Do not use bug spray with DEET on infants under two months of age. Children should be careful not to rub their eyes after bug spray has been applied on their skin. Wash children's hands with soap and water to remove any bug spray when they return indoors. o Put mosquito netting over playpens and baby carriages.

Get rid of mosquito breeding grounds

o Get rid of anything around your house and yard that collects water. Just one cup of water can produce hundreds of mosquitoes; an unused tire containing water can produce thousands of mosquitoes. o Clean your gutters and downspouts so that they can drain properly. o Remove any water from unused swimming pools, wading pools, boats, planters, trash and recycling bins, tires, and anything else that collects water, and cover them. o Remove or treat any shallow water that can accumulate on top of a pool cover. Larvicide treatments, such as Mosquito Dunks can be applied to kill immature mosquitoes. This environmentally-friendly product is available at many hardware and garden stores and on-line. o Change the water in birdbaths at least two times a week and rinse out birdbaths once a week.

Best practices for horse owners

Horses are particularly susceptible to WNV and EEE. Horse owners are advised to vaccinate their animals early in the season and practice the following:

o Remove or cover areas where standing water can collect. o Avoid putting animals outside at dawn, dusk, or during the night when mosquitoes are most active. o Insect-proof facilities where possible and use approved repellents frequently. o Monitor animals for symptoms of fever and/or neurological signs (such as stumbling, moodiness, loss of appetite) and report all suspicious cases to a veterinarian immediately. If you are unsure if your horse is properly vaccinated, you should consult with your veterinarian.

State deer season opens September 15 precautions for hunters

o Do not consume any harvested deer that appears unhealthy. Any harvested animal that is believed to be unhealthy should be reported to DEM's Division of Law Enforcement at 222-3070. o DEM recommends that hunters wear appropriate personal protective equipment when field dressing all game. At a minimum, this includes rubber or nitrile gloves and clothing that covers any part of the body that could be exposed to blood or other fluids.

For more information about DEM divisions and programs, visit Follow us on Facebook at or on Twitter (@RhodeIslandDEM) for timely updates.

Visit for additional mosquito prevention tips, videos, and local data.

Related links

  • Department or agency: Department of Environmental Management
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  • Release date: 09-10-2019

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