Early onset to mosquito season after historic SC rains


Six months after historic rains and floods left the ground saturated in many areas and with a wet spring in the forecast, South Carolina is preparing for an early onset of mosquito season.

After spraying for the bloodthirsty insects late into the fall, crews in some counties hard hit by the rains are out earlier than usual this spring to combat the swarms of mosquitoes expected to arrive when the weather warms for good.

“We’re probably about six weeks earlier than we normally would start,” said Richard Hall, the planning director in Orangeburg County, one of the areas inundated by the rains.

Crews have been out applying chemicals to kill mosquito larvae in ditches and other areas with standing water. Aerial spraying is expected to begin in the county in a week or two to kill adult mosquitoes.

The early October storm, described as one that occurs only once every 1,000 years, dumped 2 feet of rain in some areas and destroyed or damaged more than 38,000 homes.

The rain saturated fields and yards that do not usually flood and left standing water in roadside culverts. Because the rains came in autumn’s cooler weather, there was less evaporation, and trees were dormant, so they didn’t absorb the additional water through their roots. Then there was more rain over the winter.

“We still have a lot of standing water, although that water is starting to dry up in some places,” Hall said.

“We know there are more breeding areas out there so we have sort of prepared for the worst and are hoping for the best,” said Frank Carson, mosquito control manager for Charleston County. “A dry spell would be a big help.”

But the three-month outlook from the National Weather Service Climate Prediction Center predicts about a 40 percent chance of above-normal rainfall for the state.

In Horry County, on the state’s north coast, complaints about mosquitoes are already coming in and spraying is expected to begin earlier than usual, said county spokeswoman Lisa Bourcier. Crews will be treating 8,500 catch basins in the county with tablets to kill mosquito larvae, 2,500 more than last year.

It’s too early to say if soggy ground now is a prelude to a severe mosquito problem through the entire summer.

“It’s always hard to make an absolute direct connection but a lot of water remaining from last year’s rains and floods doesn’t help,” said Eric Benson, an entomologist and professor at Clemson University.

While extended periods of warm dry weather would dry things out and mean a less-severe season, that doesn’t appear likely in the short term.

Mosquitoes in South Carolina can carry a number of diseases such as West Nile virus, the Eastern Equine Encephalitis and heartworm that affects pets.

The kind of mosquito that spreads the Zika virus is found in South Carolina and other southern states as well. According to the Centers for Disease Control there have been no cases of Zika in the United States contracted from mosquitoes and no cases in South Carolina contracted by people traveling to affected areas.

The state Department of Health and Environmental Control says there are more than 60 species of mosquitoes in South Carolina. And after last fall’s storms, the agency asking communities to create, review or update local ordinances to help deter mosquito breeding. Such ordinances can require residents to clear standing water on their property where mosquitoes can breed.

Despite spraying and ordinances, the battle against mosquitoes will never really be won.

“Mosquitoes have been in South Carolina since recorded time – before you and I were here, before the Cherokee Indians were here,” Benson said. “They have pretty much been living through the seasons and their life cycles forever.”