Human cases of West Nile virus confirmed in Duval, Nassau counties

Health officials say transmission concerns increase with human cases

JACKSONVILLE, Fla. – Two human cases of West Nile virus infection have been confirmed in Duval and Nassau counties, according to health officials.

Earlier this month, officials with the Department of Health in Duval County issued warnings about the potential spread of mosquito-borne diseases after West Nile was found in several sentinel chicken flocks.

The Department of Health in Nassau County issued similar warnings in June after Eastern equine encephalitis virus was found in horses in the county. 

Duval County West Nile cases

Source: News4Jax records; Note: 1 case in 2012 was deadly

Since the beginning of 2018, four cases of EEEV infection in horses in Nassau County, and one outbreak of EEEV in emus, were reported.

Ten sentinel chickens have tested positive for EEEV in 2018, one tested positive for Highlands J Virus (HJV), and 21 tested positive for WNV, Nassau County health officials said.

West Nile Virus is a potentially deadly infection that can be transmitted to humans, according to the health department.

The human cases now confirmed increase the concern for transmission, officials said.

With several more weeks of hot weather and rain expected, authorities again reminded residents and visitors Thursday to take steps to avoid mosquito bites and limit their exposure to West Nile and other mosquito-borne illnesses.

MORE: Consumer Reports tests 25 bug repellents | 5 repellents you're wasting your money on

Below is a list of some of the things you can do to protect yourself and your loved ones:

  • Drain standing water from garbage cans and any other items around the house that can become breeding grounds for mosquitoes.
  • Check to see if the screens on your doors and windows are in good shape. If they're not, repair any broken screens as needed to keep the pests out of your house.
  • Keep your swimming pool clean and make sure it has the right level of chlorine. If you've got a plastic swimming pool, empty it when it's not in use.
  • Cover up your exposed skin with long pants and long sleeves. This is important, particularly for people who work outdoors or where mosquitoes are found.
  • Be sure to apply mosquito repellent to bare skin. Products containing DEET, picaridin, oil of lemon, eucalyptus, para-menthane-diol and IR3535 are effective.

Dr. Mobeen Rathore, chief of infectious diseases for UF Health and Wolfson, said avoiding mosquitoes is really your only protection from WNV.

"Dawn and dusk are the two times when the mosquitoes are most active, so avoid those times, but I think anything you can do to prevent mosquito bites would greatly decrease your chance of getting West Nile," Rathore said.

By and large, most people infected with West Nile do not experience any symptoms, according to the Centers for Disease Control and Prevention. But about one in five may develop a fever resulting in symptoms ranging from headaches to vomiting and diarrhea.

"That’s the thing about West Nile," Rathore said. "Maybe about 20 percent will have fever, flu-like -- that’s all they will have.They’ll feel sick, body aches and such a very small percentage will have more serious things, which include neurological problems."

In rare cases, the CDC states, those infected with West Nile may come down with a serious illness affecting the central nervous system, such as encephalitis or meningitis. Symptoms include high fever, vision loss, paralysis, tremors and coma.

Currently, there is no vaccine available to treat West Nile virus. But, according to the CDC, over-the-counter pain medication can help treat fever and other minor symptoms. Those with severe illnesses are encouraged to seek medical attention.


About the Authors:

A Jacksonville native and proud University of North Florida alum, Francine Frazier has been with News4Jax since 2014 after spending nine years at The Florida Times-Union.