This summer, the lowly mosquito has become downright worrisome for pool firms and health departments alike, especially in Texas, thanks to an epidemic of West Nile virus.

“The attention level to mosquitoes right now is double what it usually is,” said John Versfelt, president/owner of Southernwind Pools in McKinney, Texas. “This is definitely a big concern.”

More than 2,600 cases of West Nile virus, including 118 deaths, have been reported so far this year, according to the Centers for Disease Control and Prevention. That makes it the most “serious outbreak” in the country since it first appeared in the United States in 1999, according to Dr. Lyle Petersen, director of the CDC’s division of vector-borne diseases. Symptoms of West Nile virus include fever, headaches, aches and nausea.

West Nile Outbreak

The disease is typically spread by mosquitoes, which bite infected birds and then transmit the virus from person to person. Because mosquitoes breed in water, health departments have been urging people to eliminate any sources of standing water at their homes.

At Southernwind Pools, crews have been taking extra precautions at any projects that are under construction. “We’re going out and keeping the pools pumped out and clean so there is no standing water,” Versfelt said.

Southernwind’s 225 pool service customers have been getting additional care as well, with technicians checking for drainage problems or standing water in and around pool areas during their weekly maintenance checks.

But it’s not the average homeowner’s pool that’s causing problems. “Properly maintained pools do not produce mosquitoes,” said Candice Hoffmann, a spokeswoman for the CDC. “Pools that are not properly maintained and become stagnant can produce West Nile virus vector mosquitoes and should be reported to the local health department or mosquito control agency for application of appropriate mosquito control measures.”

Some have suggested that the bumper crop of mosquitoes and corresponding outbreak of West Nile may be related to the problem of stagnant water in unmaintained swimming pools at foreclosed homes, but that may simply be coincidence. “It makes perfect sense, but I think it’s a bit of an urban legend,” Versfelt said.

He could be right. Texas has been the center of the West Nile epidemic, with 1,057 reported cases (40 percent of total infections nationwide) and 46 deaths, as of mid-September.  But it has not been an epicenter for foreclosures, with just 47,000 properties (or 0.47 percent of the Lone Star State’s housing stock) in some degree of foreclosure in 2012, according to RealtyTrac. Neither has South Dakota, which has just 504 properties in foreclosure as of mid-2012, but also has the third-highest number of reported West Nile infections (144) in the nation.

Regardless of the reason for this year’s outbreak, which experts suggest could be partially due to unusually warm weather, pool professionals are taking steps to protect themselves from mosquito bites. “Everyone’s saying put on bug spray or cream and cover up,” said Eustaquio Portillo, owner of Portillo Pool Service in Garland, Texas.

West Nile virus experts believe the epidemic, which tends to be seasonal, has likely peaked. However, due to the lag time involved in getting data on infections from local health departments, CDC staff members said they expect the numbers of West Nile cases to continue to rise through the fall.