There have been no reports of the Zika virus being transmitted by mosquitoes in Florida, but the virus remains a concern for many residents.
The two mosquito species implicated in Zika outbreaks in other countries are established in Florida. They are the yellow fever mosquito, Aedes aegypti and its close relative the Asian tiger mosquito, Aedes albopictus.
It’s unclear whether Florida populations of these mosquitoes could transmit the virus, but the question will be addressed by researchers at the UF/IFAS Florida Medical Entomology Laboratory (FMEL) in Vero Beach.
Both species are invasive pests and aggressive daytime biters. Both are dark with white markings. Most significantly, both are container-inhabiting mosquitoes -- females lay eggs above the water line in water-holding containers. After a few days of drying out, the eggs are ready to hatch when the water level rises in the container. This habit makes it difficult for municipal mosquito-control programs to treat potential larval habitat sites, because they are small and numerous.
Floridians can help reduce the possibility of future problems with Zika by reducing populations of these two mosquitoes, by eliminating sources of standing water. Mosquito expert Roxanne Connelly, a professor with FMEL, offers these 10 tips and facts:
- This issue is about more than disease transmission. Day-biting mosquitoes are a huge nuisance that everyone can do without.
- This issue involves diseases besides Zika. Florida populations of the yellow fever and Asian tiger mosquito are known to vector the viruses that cause dengue and chikungunya, as well as the parasite responsible for dog heartworm.
- These mosquitoes are probably in your community. The yellow fever and Asian tiger mosquitoes are established statewide.
- Prevention pays off, and quickly. Yellow fever and Asian tiger mosquitoes are weak flyers and seldom disperse far from the site where they hatched. So, any day-biting mosquitoes you encounter on your property probably “grew up” there. Every breeding site you eliminate will reduce local populations in about a week – the time it takes for one generation to develop in warm weather.
- Scout your property once a week, preferably after a rain storm. Go out and look for standing water (we’ve supplied a list of places to check, below.) When you find standing water, the options are to Move, Maintain or Modify the container. If portable, Move to dry conditions or discard. If the item is designed to hold water, Maintain it by emptying and refilling once a week or by treating the water with a larvicide containing Bacillus thuringiensis israelensis or methoprene. It is helpful to scrub the sides of containers such as bird baths to remove any eggs that have adhered to the side. For items that can’t be moved, Modify by drilling or cutting drainage holes.
- Remember that not every “container” looks like one. A partially deflated basketball or dented piece of sheet metal can hold enough rainwater to attract container-inhabiting mosquitoes.
- Beat the bushes. When scouting your property, pay close attention to hedges, ornamental plantings, and any other thickly grown areas that might conceal trash, lost toys, etc. Bromeliad plants can hold enough water in their crowns to support mosquito larvae.
- Don’t forget the roof. Clogged gutters are a notorious mosquito breeding site.
- Protect yourself from mosquitoes while scouting. Wear protective clothing (hat, long-sleeved shirt, long pants and closed-toe shoes with socks) and a mosquito repellent containing DEET.
- Possible sources of standing water include:
LITTER – Discarded bottles and cans, plastic wrappers and bags, drinking cups, plastic or foam food boxes, broken toys, automotive debris, old tires, oyster and coconut shells;
HOUSEHOLD ITEMS – Garbage cans and recycling bins, buckets, pet food dishes, flower pots and bases, toys, garbage bags, galoshes, any watertight items stored on porches and in carports where windblown rain could reach them;
OUTDOOR ITEMS – Grills and portable fire pits, boats and other items covered by waterproof tarps, building materials, children’s play equipment, etc.;
OUTDOOR WATER CONTAINERS – Wading pools, birdbaths, rain gauges, rain barrels;
ABOVE-GROUND ITEMS – Clogged gutters, dents in the roofs of porches, carports or tool sheds.
For more information, UF/IFAS experts have prepared a free booklet, Florida Resident’s Guide to Mosquito Control.