Website to help in war against mosquitoes

May 29, 2009

A website has been launched to help in the seasonal battle against mosquitoes in the US, which carry serious diseases which affect horses and humans.

Worldwide, mosquito-borne diseases kill over one million people each year and sicken more than 700 million people annually.

In the US, Western Equine Encephalitis, Eastern Equine Encephalitis and West Nile Virus are among the most serious concerns.

"This is a critical time because of all the rain that we've had recently," said Mike Merchant, an urban entomologist with the Texas AgriLife Extension Service in Dallas.

"We are beginning to see our first big influx of floodwater mosquitoes in the area," he said. "Over the next few days we should start seeing more mosquitoes coming out from creek bottoms and river bottoms, which are areas where they tend to breed."

Those that have bred in water-filled containers will also be on the increase over the next few weeks, invading backyards and other prime breeding areas as they grow in numbers, he said.

To help Americans prepare for the mosquito onslaught, Merchant and others have developed Mosquito Safari (http://mosquitosafari.tamu.edu) to teach people about mosquitoes and how to control them.

Merchant said there isn't much people can do to keep floodwater mosquitoes from being a problem when venturing outdoors other than wearing a good insect repellent with the active ingredient DEET. That's because floodwater mosquitoes move easily from their breeding sites, he said. These mosquitoes breed in standing water near creeks and rivers after flooding in residential areas.

"Floodwater mosquitoes are really strong fliers, so you can live far from a creek and still be affected by them," Merchant said "They're there all the time and they're going to come out after any big rain. They can fly up to five to 10 miles from their breeding sites and affect people who don't even live close to water. This affects everyone in the metroplex in any community."

The good news, however, is that floodwater mosquitoes don't tend to carry diseases that affect people, Merchant said.

Container-breeding mosquitoes, on the other hand, can carry important diseases such as West Nile virus, he said. But people can do a lot to control them.

"To find these pests, you really do need to go out on safari in your backyard, which is the origin of the website's name," Merchant said. "The goal of a mosquito safari is to search out and eliminate places where disease-carrying mosquitoes breed."

Container-breeding mosquitoes breed in anything that can catch and hold water along with leaf or lawn debris, he said, including soft drink cans, open grills, watering cans, clogged gutters, wheel barrows and puddles. Generally, breeding can be prevented by dumping water and clearing debris.

Morgan Kohut, an entomologist with the Dallas County Department of Health and Human Services, said that people can easily "D-fend" themselves against mosquito bites and West Nile by remembering the "three D's: drain, dress and DEET".

"It is important to get rid of all standing water," Kohut said. "Change the water in pet dishes and birdbaths several times a week and prevent possible breeding sites by emptying, removing, covering or turning containers upside down."

Hiring a pest control professional or using sprays and other do-it-your-self methods may be necessary to protect yourself and home, Merchant said. Detailed information can be found on Mosquito Safari.

In addition to showing the most common places for mosquitoes to breed, the site discusses mosquito biology and control methods, including repellents for people and sprays for foliage. It describes what homeowners can do to prevent the insects from breeding in yards and alleys.

The site was designed for a national audience, including both the general public and pest control professionals, Merchant said.

Merchant said he hopes public health agencies link to Mosquito Safari from their websites.

The American Mosquito Control Association, City of Dallas Health Department and Dallas County Health Department already have set up links.

Mosquito Safari is sponsored by the Texas AgriLife Extension Service, Dallas County Health Department and the US Environmental Protection Agency - Region 6 Pesticides Division.