PROVIDENCE, RI – The Department of Environmental Management (DEM) announced today that the latest round of mosquito testing by the Rhode Island Department of Health (RIDOH) State Health Laboratories confirmed the second detection of West Nile Virus (WNV) in the state. summer. As with the first WNV find announced by DEM on August 17, the second sample was collected in Westerly. The RIDOH test did not detect new positives for Eastern Equine Encephalitis (EEE). During the week of August 23, DEM collected 83 mosquito samples from 37 traps set statewide. The results of the mosquitoes collected during the week of August 29 are awaited.
Although WNV has now been detected twice from the same Westly trap site, state officials stress that the disease is more common than EEE at this stage of the mosquito season and is likely circulating in mosquitoes throughout the state. WNV is the leading cause of mosquito-borne disease in the continental United States. WNV cases occur during the mosquito season, which begins in the summer and continues into the fall. There are no vaccines or drugs to prevent WNV in humans. Fortunately, most people infected with WNV do not feel sick. About one in five people infected develop a fever and other symptoms. About 1 in 150 infected people develop serious, sometimes fatal, disease. You can reduce your risk of WNV by using insect repellent and wearing long-sleeved shirts and long pants to avoid mosquito bites. DEM and RIDOH advise Rhode Islanders to reduce their exposure to mosquitoes before the first hard frost. A hard frost is when the air and ground freeze below 32°F for three hours or below 28°F for two hours.
To date, 151 positive WNV samples have been reported in Connecticut, but there are no cases of WNV in humans or animals and no EEE in mosquitoes, humans, or animals. Massachusetts reports 64 positive WNV samples and one human case and no EEE in mosquitoes, humans, or animals.
Personal protection is the first line of defense against mosquitoes that may carry WNV, EEE or other diseases and is the most effective way to prevent infection. With WNV established in the state, residents are reminded to eliminate mosquito breeding areas and avoid biting whenever possible. The following precautions are recommended.
- Put screens on windows and doors. Fix blank or holey screens.
- Consider retiming outdoor activities between sunrise and sunset (when EEE-carrying mosquitoes are most active), evening, or early morning. If you must be outside, wear long-sleeved shirts and long pants and use bug spray.
- Use an EPA-approved bug spray with one of the following active ingredients: DEET (20-30% strength); picaridin, IR3535; and lemon eucalyptus or paramentan oil. Always read the label and follow all directions and precautions.
- Do not use bug spray with DEET on babies younger than two months. Children should be careful not to rub their eyes after applying bug spray to their skin. When children return home, wash their hands with soap and water to remove any bug spray.
- Place mosquito netting over playgrounds and strollers.
Remove areas where mosquitoes breed
- Remove anything that collects water around your home and yard. Just one glass of water can produce hundreds of mosquitoes; An unused tire with water in it can create thousands of mosquitoes.
- Clean your gutters and downspouts so they drain properly.
- Remove and cover any water from unused pools, wading pools, boats, planters, trash and recycling bins, tires, and anything that collects water.
- Remove or treat any shallow water that may collect on top of the pool cover. Larvicidal treatments such as Mosquito Dunks can be used to kill immature mosquitoes. This eco-friendly product is available at many hardware and garden stores and online.
- Clean and change the water in birdbaths at least 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 to:
- Remove or cover areas where water may collect.
- Avoid taking pets outside in the morning, evening or at night when mosquitoes are most active.
- Use insect repellents and often approved repellents if possible.
- Monitor animals for fever and/or neurologic signs (eg, limping, moodiness, loss of appetite) and report all suspected cases to the veterinarian immediately. If you are unsure whether your horse has been properly vaccinated, you should consult your veterinarian.
For more mosquito prevention tips, videos and local information, visit health.ri.gov/mosquito. Mosquitoes are captured weekly by DEM and tested at RIDOH State Health Laboratories. DEM issues recommendations on test results from June to September and issues additional reports as needed. Typically, positive test results trigger additional traps to assess risk.
For more information on DEM programs and initiatives, visit www.dem.ri.gov. Follow DEM on Facebook, Twitter (@RhodeIslandDEM) or Instagram (@rhodeisland.dem) for timely updates.