NEW SHOREHAM, R.I. (WPRI) — The R.I. Department of Environmental Management (DEM) announced Tuesday that mosquito samples collected last week have tested positive for eastern equine encephalitis (EEE) and West Nile virus.

The DEM said a mosquito sample collected at Boy Scout Camp Sandsland on Block Island tested positive for EEE, while West Nile virus was detected in a sample from Westerly.

This is the first time EEE has been detected outside of Glocester this season. The DEM opted to close its recreational sites in Glocester after five mosquito samples tested positive for the disease.

No human cases of EEE have been reported in the state this year, but a donkey in Glocester did contract the virus.

The Boy Scouts of America has closed its camps located in Glocester and on Block Island for the remainder of the season as a result of the latest finding, according to the DEM.

The state has also seen an increase in the presence of West Nile virus. The DEM said 12 mosquito samples have tested positive so far this season, including six in Westerly, two in Barrington, and one each in Cranston, Johnston, Richmond and Tiverton.

Locations are not exact and are meant to illustrate findings by community. Source: RI DEM/RI DOH

Both EEE and West Nile virus can only be contracted through a bite from an infected mosquito. Though extremely rare in humans, EEE is considered one of the most serious mosquito-borne illnesses that can cause neurological issues without supportive treatment.

West Nile virus, on the other hand, is much more prevalent than EEE and is considered the leading cause of mosquito-borne disease nationwide. The vast majority of those who contract West Nile virus don’t experience symptoms, and those who do typically recover within a week’s time.

The DEM said the risk for mosquito-borne illnesses typically lasts until the first hard frost, which is meteorologically defined as three straight hours with temperatures below 32 degrees.

In the meantime, Rhode Islanders should take the following steps to prevent mosquito bites:

Protect yourself

  • Put screens on windows and doors. Fix screens that are loose or have holes.
  • At sunrise and sundown (when mosquitoes that carry EEE 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.
  • 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.
  • Do not use bug spray with DEET on infants under two months of age. Check the product label to find the concentration of DEET in a product. The American Academy of Pediatrics recommends that repellents should contain no more than 30% DEET when used on children. 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.
  • Put mosquito netting over playpens and baby carriages.

Remove mosquito breeding grounds

  • Remove items around your house and yard that collect water. Just one cup of water can produce hundreds of mosquitoes; an unused tire containing water can produce thousands of mosquitoes.
  • Clean your gutters and downspouts so that they can drain properly.
  • 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.
  • 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 online.
  • Clean and change water in birdbaths at least once a week.

Best practices for horse owners

Horses are particularly susceptible to West Nile virus 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 repellents 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.