SC Health Department Gets “Imminent Threat to Public Health” Designation for Encephalitis-Carrying Mosquito

The Suffolk County Health Department received approval on Aug. 25 for the county’s request for a declaration of an “Imminent Threat to Public Health” from the New York State Commissioner of Health, after a mosquito in Manorville tested positive for Eastern Equine Encephalitis, a highly deadly illness that can pass from mosquitos through other vectors to humans.

“The Imminent Threat to Public Health designation will allow the county to address the mosquito issue in areas that would not be accessible without the designation. It will also allow the county to be reimbursed at a greater percentage for its efforts to control mosquitoes that cause disease,” according to the Suffolk County Health Department.

The health department reports that it is “in the process of finalizing plans to address this issue next week” and further information will be forthcoming.

“The reason EEE is less common in humans is that the primary mosquito vector, Culiseta melanura, does not typically feed on humans,” said Suffolk County Health Commissioner Dr. James Tomarken. “However, the virus may be transmitted to humans and horses by bridge vectors, which are other kinds of mosquitoes that have contracted the virus by feeding on infected birds.”

While a vaccine against the virus is recommended for horses, eastern equine encephalitis is a rare but deadly illness for humans. Approximately 5 to 10 human cases of EEE are reported annually in the U.S. New York State has reported just 12 cases of EEE since 1952. To date, there have been no human cases in Suffolk County.  The last reported positive mosquito for EEE in Suffolk County was in 2008.

In severe cases of EEE, a person may experience encephalitis, or swelling of the brain, which may result in death. According to the Suffolk County Health Department, the mortality rate for humans with EEE is about 33 percent, the highest among human insect-borne viruses. There is currently no human vaccine for EEE and patients are treated with supportive care.

The mortality rate for horses that contract the disease ranges from 75 to 90 percent. In 2016, the USDA reported 118 cases of EEE in horses from 15 states, including two from upstate New York. Suffolk County reported three cases of EEE in horses in 2003. 

According to the health department, “owners of equines have an essential role in preventing EEE from spreading. Horse owners are encouraged to vaccinate their animals and put safeguards in place that prevent animals’ exposure to mosquitoes as well as report any suspicious signs of EEE in animals to a veterinarian.”

The county health department also reported Aug. 24 that 16 more mosquitoes collected on Aug. 15 and 16 tested positive for West Nile Virus, including one in Aquebogue, one in East Hampton and two in Southold.

To date this year, Suffolk County has reported 92 mosquito samples and nine birds confirmed positive for West Nile virus.  No humans or horses have tested positive for West Nile virus in Suffolk County this year.

West Nile Virus symptoms may include fever, headache, vomiting, muscle aches, joint pain, and fatigue. There is no specific treatment for West Nile virus. Patients are treated with supportive therapy as needed.

The Suffolk County Department of Health Services is asking residents to help control the mosquito population by eliminating standing water on their property, and is asking the public, especially those who live in or visit the Manorville area, to be even more vigilant.

The health department is urging people over age 50 or with compromised immune systems to take extra precautions, and is recommending the general public follow the following guidelines:

• Minimize outdoor activities between dusk and dawn.
• Wear shoes and socks, long pants and long-sleeved shirts when mosquitoes are active.
• Use mosquito repellent, following label directions carefully.
• Make sure all windows and doors have screens, and that all screens are in good repair.
• Keep mosquitoes from laying eggs inside and outside of your home. Once a week, empty and scrub, turn over, cover, or throw out containers that hold water, such as vases, pet water bowls, flowerpot saucers, discarded tires, buckets, pool covers, birdbaths, trash cans and rain barrels.
• Download a copy of Suffolk County’s informational brochure “Get the Buzz on Mosquito Protection,” available in English and Spanish, and share it with your community.

Dead birds may also indicate the presence of West Nile virus. To report dead birds, call the Public Health Information Line in Suffolk County at 631.787.2200 from 9 a.m. to 4:30 p.m., Monday through Friday.  Residents are encouraged to take a photograph of any bird in question.

To report mosquito problems or stagnant pools of water, call the Department of Public Works’ Vector Control Division at 631.852.4270.

For more information on mosquito borne illnesses, visit the Department of Health Services’ website here.