The Who, What, Where, When and Why of Mosquitoes and West Nile Virus
West Nile Virus is at the forefront of people’s minds lately, so the experts at
Orkin, a wholly owned subsidiary of Rollins Inc. (NYSE: ROL), have developed answers
to five frequently asked questions.
Q: I have surveyed my yard, and I do not see any places for standing water. Are
there places I am not thinking about or seeing that could have standing water?
A: Yes, there are probably several unexpected mosquito breeding
areas around your property. Besides emptying the obvious flower pots, bird baths
and old tires of water, make sure to clean gutters and downspouts regularly or cover
with mesh to prevent leaves and debris from collecting and holding water. Children’s
toys, swings, slides and playgrounds can have small crevices where water can collect.
A few other odd places you may not have considered: your car, landscape statues,
rain gauge, garden hoses and even large plant leaves. If a full plastic garbage
bag sits in the rain, it can develop a small pocket where water can collect. Remember,
it only takes about a cup of water for mosquitoes to breed. And just because your
yard may be free of standing water, does not mean your neighbor’s yard is too.
Q: Why are there so many cases of West Nile Virus this year? Are there more mosquitoes?
A: Many experts point to last year’s mild winter and the scorching
temperatures this summer, helping the mosquitoes thrive. Several areas of the country
are facing water-use restrictions because of the drought, but even a little bit
of water from a thunderstorm, washing your car or watering your lawn can be enough.
It is also important to note, especially since we are in hurricane season, that wind
can displace mosquitoes, including those that carry West Nile Virus. The virus is
carried in and transmitted by birds, and wind can also move birds to different areas.
Q: I thought this was the end of mosquito season, so how much longer do we need
to worry about this?
A: This is the peak mosquito breeding season, not peak West Nile
Virus season. It often takes two to 15 days for the virus to show any symptoms,
so it could be a few more weeks until we are in the clear. Temperatures need to
be around freezing before mosquitoes will start to die off. In some places, mosquitoes
can be seen until October or even later.
Q: Is it true that mosquitoes do not need water to breed, and can just lay their
eggs in wet dirt?
A: Most mosquito species prefer to lay eggs at the edge of water
bodies against mulch, grass, foliage or refuse that will hold the eggs at the surface
of the water. If the water evaporates—or you pour it out—before the eggs develop,
which usually takes about 7 to 10 days, the eggs will not develop completely into
adults, and they will die. If water is not present, those eggs can sit for months
until there is enough water to float the eggs to develop and feed the larvae. That
is why, even though much of the country is in a drought, mosquitoes are still active.
Q: Can my pool encourage mosquito breeding?
A: Typically, mosquitoes do not breed in pools because they prefer
nonmoving water. But if the pool has been neglected, mosquitoes can certainly use
that water to breed. Also, chlorine and other pool chemicals inhibit breeding.
It is important to check unexpected places for standing water, and homeowners can
do a lot to decrease their chances of getting bitten by mosquitoes. Orkin experts
recommend people take the following precautions to protect themselves:
- Protect yourself: wear EPA-approved insect repellent along with long-sleeved shirts
and long pants.
- Stay indoors during dusk and dawn and an hour before and after dusk and dawn. Those
are the times of day when mosquitoes are most active.
- Protect your yard: call a professional pest control company for a customized mosquito
inspection and treatment program.
- Replace outdoor light bulbs with yellow bulbs that are less attractive to mosquitoes.