A deadly mosquito-borne virus that causes brain swelling in humans has been detected in Florida
Michelle Lou, July 28, 2019
CNN – Florida health officials are warning of an uptick in a mosquito-borne virus known as Eastern equine encephalitis (EEE).
Several sentinel chickens tested positive for EEE, which can spread to humans via infected mosquitoes and cause brain infection and swelling, the Florida Department of Health in Orange County said in a Thursday statement.
Sentinel chickens are fowl that are tested regularly for the West Nile virus and EEE. Their blood can show the presence of the diseases, but they don’t suffer from the effects of the viruses.
Following the positive tests for the sentinel chickens in Orange County, the health department said “the risk of transmission to humans has increased.”
Only about seven cases of the EEE virus in humans are reported in the US each year … Read more.
Eastern equine encephalitis virus (EEEV) is transmitted to humans through the bite of an infected mosquito.
Human EEEV cases occur relatively infrequently, largely because the primary transmission cycle takes place in and around swampy areas where human populations tend to be limited.
All residents of and visitors to areas where EEEV activity has been identified are at risk of infection.
People who engage in outdoor work and recreational activities in endemic areas are at increased risk of infection.
Persons over age 50 and under age 15 seem to be at greatest risk for developing severe disease when infected with EEEV.
Overall, only about 4-5% of human EEEV infections result in EEE. EEEV infection is thought to confer life-long immunity against re-infection. It does not confer significant cross-immunity against other alphaviruses (e.g., western equine encephalitis virus), and it confers no cross-immunity against flaviviruses (e.g., West Nile virus) or bunyaviruses (e.g., La Crosse virus).
In the United States, an average of 7 human cases of EEE are reported annually. To ensure standardization of reporting across the country, CDC recommends that the national surveillance case definition be consistently applied by all state health departments.
Most cases of EEE have been reported from Florida, Massachusetts, New York, and North Carolina. EEEV transmission is most common in and around freshwater hardwood swamps in the Atlantic and Gulf Coast states and the Great Lakes region.