Rare type of encephalitis reported in Hillsborough
For the first time in three years, a Hillsborough County resident has been infected with a rare and serious mosquito-borne illness, health officials said Monday.
When Eastern equine encephalitis was last locally reported in humans in 2010, a 2-month-old baby and an adult woman died. This time, doctors and epidemiologists expect the person to see a full recovery from the illness, which kills a third of those infected.
Health officials declined to identify the gender or age of the individual, but said the person was infected in early March in northwest Hillsborough, a less-populated area where mosquitoes are more likely to congregate.
The person remains under a doctor's care, but may not suffer any long-term damage from the infection, which can cause swelling of the brain.
“There's absolutely no impairment we can see,” said Amanda Pullman, an epidemiologist with the Florida Department of Health, Hillsborough County.
Five to 10 human cases of Eastern equine encephalitis are discovered each year in the United States, according to the Centers for Disease Control and Prevention. Most cases happen in Southern Gulf Coast region states, during the hot, wet summer season.
Pullman said the odd, winter timing of this new case led to additional lab tests, which confirmed Eastern equine encephalitis over the weekend. Local health officials are urging doctors to test patients displaying symptoms such as fever, headache, irritability, restlessness, drowsiness, anorexia, vomiting, diarrhea, cyanosis, convulsions and coma.
Also, Hillsborough mosquito control workers are taking steps to prevent additional infections. Within 24 hours of the case being reported, the neighborhood where the infection happened was sprayed. Extra mosquito traps were put in place and additional testing will be continued by the health department and mosquito control through the summer, Pullman said.
“Because the response was so quick, we hope to not see additional cases,” she said.
Mosquitoes are the lone source of infection of Eastern equine encephalitis to humans and horses. They transmit the disease after biting birds that carry the virus, and symptoms can start to appear four to 10 days after infection.
Florida is by far the state with the most reported cases of Eastern equine encephalitis. Between 1964 and 2010, officials reported 70 human cases in the Sunshine State. Georgia came in second, with just 28 cases during the same time period, the CDC says.
In 2012, just one Floridian – in Holmes County -- reported being infected with the disease, CDC tracking data show. But that same year, health officials identified 85 cases in sentinel chickens, including four in Hillsborough County.
Pullman said the state's mild winter should be a reminder that mosquitoes can appear – and bite -- anytime. Preventative steps, such as wearing long-sleeve shirts and long pants, and using insect repellant with DEET are a good idea all year long.
“People need to understand it's not just midsummer when you need to protect yourself,” she said. “… It's Florida. We get too complacent.”