There are two diseases that are carried by mosquitoes which are of concern for Alachua County residents and
visitors. These diseases, called arboviruses, are Eastern Equine Encephalitis (EEE), and West Nile
Virus (WNV). While both can be fatal, EEE has the higher death rate, and covers a wider age group for serious
symptoms. While WNV can certainly affect all groups, it is predominately a serious disease for those over 55 years
old. Symptoms however, in both age groups can range from mild or unapparent, to the onset of fever and general
malaise. The most serious cases have this as well as full encephalitic symptoms, such as delirium, coma, and death.
As stated, the death rate in EEE is higher, but also this disease carries a higher rate of ongoing problems for
those that survive it.
Arboviruses are predominately diseases of birds, which serve as reservoirs and
amplifiers of the infection in a community. It is only when an infected bird is bitten by mosquitoes that feed on
birds and other hosts that infection occurs. While different mammals can get infected, the predominate species
infected are horses, and to a much lower extent, humans. A vaccine is available for horses for both EEE and WNV,
and horse owners should contact their veterinarian for the proper schedule for vaccination against both diseases.
Fatality rates for EEE in horses are as much as 95% and 35% for WNV. There is no human vaccine available for either
Prevention of these diseases in humans begins with the individual taking their basic precautions. We commonly refer
to these as the "Five D's" of prevention.
- The mosquitoes that we are most concerned about feed primarily at Dawn and Dusk. Avoiding activity
at these times reduce risk.
- Dress appropriately. If you are out at these times, the use of barrier clothing, such as long sleeves and
pants, reduce skin exposure.
- The use of chemical repellants containing DEET are recommended. Use these repellants in accordance with
package instructions, and for appropriate age groups as listed on the product.
- Finally, assure that your Drains are free of standing water. This includes gutters, flower pots, wading
pools, and virtually anything that will hold even small amounts of standing water.