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Sunday, July 1, 2018

First tests of mosquitos shows signs of EEE

Later tests can’t confirm
DEM Weekly Mosquito Advisory

mosquito GIFThe Rhode Island Department of Environmental Management (DEM) announced that 53 mosquito samples from 13 traps set on Monday, June 11; 106 samples from 33 traps set on Monday, June 18; and 15 samples from three traps set on Wednesday, June 20 have tested negative for both West Nile Virus (WNV) and Eastern Equine Encephalitis (EEE).

In addition, EEE was detected in mosquito samples from three traps set on June 11; however, this highly unusual and uncommon finding was not substantiated by traps set at the suspect sites on both June 18 and June 20. 

To date, in Rhode Island, there have been no findings of WNV in mosquito samples. On June 26, Connecticut and Massachusetts reported this year's first findings of WNV in mosquito samples.

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 health.ri.gov/mosquito 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.

Last year, the RIDOH State Health Laboratories changed their testing methodology to use a more sensitive testing method which may account for an increase in positive results going forward. DEM issues advisories on test results from late June through September, with additional reports as necessary.

Test results are pending for traps set on June 25 and will be included in future announcements. Typically, positive test results trigger additional trapping to assess risk.

For more information about DEM divisions and programs, visit www.dem.ri.gov. Follow us on Facebook at www.facebook.com/RhodeIslandDEM or on Twitter (@RhodeIslandDEM) for timely updates.

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