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Friday, August 31, 2018

DEM gets three more positive test results for West Nile Virus

Weekly Mosquito Advisory

Image result for mosquitoesThe Rhode Island Department of Environmental Management (DEM) announces that test results from three mosquito pools, or samples, from traps set in Central Falls, Cranston, and Tiverton have been confirmed positive for West Nile Virus (WNV).

Since July 31, eight mosquito samples from six communities – the three mentioned above plus Pawtucket, Providence, and Warren – have tested positive for WNV. Four samples have tested positive for Eastern Equine Encephalitis (EEE) to date.

The three positive findings came from 34 mosquito traps set by DEM staff on August 20 and tested at the Rhode Island Department of Health (RIDOH) State Health Laboratories. The remaining 135 samples from the 34 traps set August 20 tested negative for WNV and EEE.

"These findings are not unexpected. Regional data suggest this is a higher-than-normal risk year for WNV," said Alan Gettman, state Mosquito Abatement Coordinator. "Last week Massachusetts raised the risk level from low to moderate statewide, and Connecticut officials also have recently advised residents of increased WNV activity. Late summer-early fall always is the peak season for human risk, so it's especially important now to take precautions if you go outside."

Personal protection is the first line of defense against mosquitoes that may carry WNV, EEE, or other diseases – and the most effective way to avoid infection. With WNV and EEE established throughout the state, DEM and RIDOH remind the public to eliminate mosquito breeding grounds and prevent being bitten, whenever possible. The following precautions are advised:

• Remove anything around your house and yard that collects water; just one cup of water can produce hundreds of mosquitoes.

• Clean gutters and downspouts to ensure proper drainage, and repair holes in window screens. 

• 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.

• Change the water in birdbaths at least two times a week, and rinse out birdbaths once a week.

• Use EPA-approved bug spray with one of the following active ingredients: DEET (at least 20% strength), picaridin, IR3535, and oil of lemon eucalyptus or para-menthane-diol.

• Minimize outdoor activity at dawn and at dusk when mosquitoes are most active.

• Put insect netting over strollers and playpens.

• Wear long sleeves and long pants whenever possible, particularly if you are outdoors during dawn and dusk.

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

• Remove or cover areas where standing water can collect.

• Avoid putting animals outside at dawn, dusk, or during the night when mosquitoes are most active.

• Insect-proof facilities where possible and use approved repellants frequently.

• 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.

Visit for additional mosquito prevention tips, videos, and local data. DEM and RIDOH also remind Rhode Islanders to take precautions to avoid mosquito bites when traveling to Zika-affected countries. Pregnant women and women who are considering becoming pregnant should not travel to countries with active transmission of Zika.

Mosquitoes are trapped weekly by DEM and tested at the RIDOH State Health Laboratories. DEM issues advisories on test results from late June through September, with additional reports as necessary. Typically, positive test results trigger additional trapping to assess risk.
For more information about DEM divisions and programs, visit Follow us on Facebook at or on Twitter (@RhodeIslandDEM) for timely updates.
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