City of Jacksonville


Mosquito-Borne Encephalitis

Jacksonville's Mosquito Control Division works closely with the Duval County Health Department to monitor for mosquito-borne encephalitis such as Eastern Equine Encephalitis (EEE), St. Louis Encephalitis (SLE) and West Nile Virus (WN). The primary form of surveillance for these viruses are sentinel chickens. Flocks are placed around the county from mid-May to late November or December to track the presence of the viruses in Jacksonville.

As of 2012, the Mosquito Control Division has increased surveillance for the mosquitoes that can transmit Dengue (DEN), Chikungunya (CHIK) and also Zika  (ZIK) viruses. Unlike WN virus, we cannot use chickens as an early detection system for these specific viruses. We routinely coordinate with the local health department and respond quickly with mosquito surveillance and appropriate treatments when necessary. The mosquitoes, Aedes albopictus and Aedes aegypti have a specific activity period from end of April through end of September. Click on the mosquito name for more information on where these mosquitoes breed and how to easily reduce their breeding sites.

If surveillance has shown the presence of a mosquito-borne virus in an area, technicians look for a potential mosquito breeding sources. Once found, they are either eliminated or treated. Increased treatments for the presence of adult mosquitoes are also performed in conjunction with the inspections. Mosquito Control's goal is to minimize the potential for virus transmission by decreasing the adult, flying mosquito population.

The Florida Department of Health recommends that the public practice "Drain and Cover" for personal mosquito protection. 

Drain standing water to stop mosquitoes from multiplying.

  • DISCARD: Old tires, drums, bottles, cans, pots and pans, broken appliances and other items that aren't being used.

  • EMPTY and CLEAN: Birdbaths and pet's water bowls at least once or twice a week.

  • PROTECT: Boats and vehicles from rain with tarps that don't accumulate water.

  • MAINTAIN: The water balance (pool chemistry) of swimming pools. Empty plastic swimming pools when not in use.

Cover your skin with clothing and use mosquito repellant.

  • CLOTHING: If you must be outside when mosquitoes are active, cover up. Wear shoes, socks, long pants, and long sleeves.

  • REPELLENT: Apply mosquito repellent to bare skin and clothing. Always use repellents according to the label. Repellents with DEET, picaridin, oil of lemon eucalyptus, and IR3535 are effective. Use mosquito netting to protect children younger than 2 months.

Cover doors and windows with screens to keep mosquitoes out

(Refer to the following web page Avoiding Mosquitoes  for more tips on how to avoid, repel, and eliminate mosquitoes around your home) or check the Florida Department of Health's prevention website.

For more information on mosquito-borne viruses, refer to the Center for Disease Control (CDC) or the Florida Department of Health.