Duval issues health alert for West Nile virus

Public health authorities issued a mosquito-borne illness alert Monday for Duval County after confirming the 11th human case of West Nile virus in Jacksonville this year.

The county has recorded 58 percent of the state's 19 cases reported so far this year.

West Nile virus is a potentially deadly infection that can be transmitted to humans via mosquitoes.

No West Nile virus human infections were reported last year in Duval County, according to Florida Department of Health, Division of Public Health Statistics and Performance Management data.

Multiple factors likely are responsible for Duval's human infections this year, public health officials said. 

"Mosquito-borne disease activity is driven by many factors, including the presence of types of mosquitoes that can transmit a particular virus, as well as presence of the animal reservoir that can infect biting mosquitoes," said Nick Van Der Linden, interim communications director for the Florida Department of Health.

Several types of birds can act as natural reservoirs for West Nile virus. Environmental factors such as rainfall and temperature are also important, he said.

"When these and other factors align, you can see increased disease activity in a particular area," said Van Der Linden, noting they're also seeing West Nile cases in other counties.

Alison A. Hewitt, a spokeswoman for the Florida Department of Health-Duval County, said another factor is that it's a seasonal occurrence, which can vary. The county's large size also is a factor, she said.

City Mosquito Control and Duval County health department are continuing surveillance and prevention efforts. Health department officials advise people not to focus on the specific location of the confirmed cases because mosquitos that can spread West Nile virus are capable of traveling at least five miles. Birds infected with the disease can go even farther.

As of Nov. 13, a total of 2,323 cases of West Nile virus infections in people nationwide have been reported this year to the Centers for Disease Control and Prevention.

Those cases included 1,428 or 61 percent that were classified as neuroinvasive disease such as meningitis or encephalitis. A total 895 or 39 percent were classified as non-neuroinvasive disease. according to CDC data.

That data show the 2018 Florida cases of West Nile human infection totaled 19 statewide including one death as of Nov. 13.  Florida Department of Health data showed 19 cases as of Nov. 17.

Van Der Linden said an upcoming report with updated numbers will indicate Duval has 39 percent of the West Nile Virus illnesses acquired in Florida as opposed to 58 percent.

In 2017, the state's West Nile virus cases totaled five and no deaths were reported, CDC data shows.

The Florida Department of Health also continues to conduct statewide surveillance for mosquito-borne illnesses including West Nile virus infections, Eastern equine encephalitis, St. Louis encephalitis, malaria, chikungunya, and dengue.

The department urges residents to report dead birds via the Florida Fish and Wildlife Conservation Commission’s website http://legacy.myfwc.com/bird/default.asp.

For more information http://www.floridahealth.gov/diseases-and-conditions/mosquito-borne-diseases/index.html or call the local county health department.

Teresa Stepzinski: (904) 359-4075