By Andy Rathbun

St. Paul Pioneer Press

Noticing more mosquitoes than usual? You’re not imagining things — numbers are up in the Twin Cities metro and across the state because of early summer’s heavy rains.

But there’s good news, too. The bug’s peak has come and gone, and the population is now on the decline.

“It kind of peaks after the Fourth of July and then starts to go down,” said Mike McLean, public information officer for the Metropolitan Mosquito Control District. “People are still getting bit by mosquitoes, but it’s not nearly as intense as it was two or three weeks ago.”

As the numbers begin to fall, the Metropolitan Mosquito Control District, which works to control the insect’s population, shifts its attention from the most annoying kinds of mosquitoes to species that can carry disease, such as the West Nile virus.

Although no one in Minnesota has reported catching the virus this summer, the agency has found the disease in mosquitoes and a bird, McLean said.

In Minnesota, the main species of mosquito that can carry West Nile is called Culex tarsalis, a prairie species that prefers a wet spring and early summer followed by dry conditions and hot days. The Twin Cities had the wet spring and early summer, and conditions in July have been dry. But temperatures have been restrained.

The average temperature for July at the Minneapolis-St. Paul International Airport was running 2.4 degrees below normal through Tuesday, and the month has had only two days with temperatures in the 90s.

“It’s not looking like we’re going to get the really warm weather that would make for a bad West Nile season if you look at the long-term forecast,” McLean said. “I don’t want to say that we’re out of the woods, but the last two years have been pretty intense when it came to West Nile virus. This year, maybe not so much.”

Since Culex tarsalis was first found in the state in 2002, Minnesota has seen cases of the virus every year. The numbers can vary greatly — from a low of two cases in 2011 to a high of 148 cases in 2003. The past two years have been on the higher end, with 70 cases in 2012 and 80 in 2013.

Most infected people will not have symptoms.

Some develop a fever, and a small percentage can develop meningitis or encephalitis. Of 615 West Nile cases reported in the state, 19 have been fatal, said Dave Neitzel, supervisor for the vector-borne disease unit at the state Health Department.

The season for West Nile typically peaks in August and extends into September, Neitzel said, adding that this is most important time of the year to take precautions against mosquitoes, especially at dusk and dawn.

Heavy rains in May and June resulted in a lot of standing water, which prompted the Metropolitan Mosquito Control District to intensify its metro campaign against mosquito larvae. McLean said those extra efforts resulted in the agency exhausting its annual budget for the treatments. He said the agency still has other funds to tap should more treatments be needed.