“The rise of the dormant mosquitoes” isn’t the name of a new science-fiction thriller; it’s what’s happening across the region this summer.
State officials and insect experts say this year is one of the buggiest in recent memory. Previously dormant mosquito larvae are hatching, likely because of the wet weather conditions, creating an influx of the bloodsucking pests, they say.
“Some (mosquito) species lay eggs directly on water, or where water will inundate the eggs,” said Piera Siegert, the N.H. state entomologist. “But they can survive in that egg stage for many, many years if they’re not inundated.”
In fact, “the eggs can be 30 feet up a river bed, so if it only floods 15 feet, they won’t hatch,” said Kimberly A. Foss, director of biology and surveillance for Municipal Pest Management Services in Portsmouth, which serves clients throughout the state, including the city of Keene.
This year, the hot and humid conditions, coupled with lots of rain, mean long-dormant mosquito eggs are hatching left and right, Foss said.
“You can have a higher population if those areas get flooded, and that’s what happens with freshwater rain events, like this year,” she said.
Keene, in particular, is susceptible to mosquito storms because of its geography and proximity to a number of water bodies, Foss said.
“Keene is kind of primed for this activity, with two large rivers, and the flood plains associated with those rivers, which are large, flat areas, and the water will flood right into that area, stay there, and then the larvae hatch,” she said.
Siegert said state health officials are preparing to run tests next month on the state’s mosquito populations to see if any test positive for Eastern Equine Encephalitis (EEE), West Nile virus, or any other diseases that can be contracted by humans through mosquito bites. But preliminary tests have not shown any signs of local mosquitoes carrying those diseases, she said.
It’s been a while since mosquito infestations were this intense, Foss said.
“The other year I can probably compare this to ... 2009, when we had three months of rain for the summer,” she said. “It’s not quite as bad as that ... but roadside ditches, lawns, any places that can hold water for a long time, that’s where we’re having the problem.”
Buckets that collect rain water, kids’ toys left outdoors, including kiddie pools, and any item capable of holding water over a period of time are all easy marks for egg-laying mosquitoes, Foss said. Those spots, she said, are more prone to mosquito species that carry EEE and West Nile virus.
But while it’s good to take precautions, Siegert doesn’t believe those mosquito-borne diseases are likely to reach epidemic proportions.
“I think people should always be taking precautions against mosquito bites, because any time you have an organism that’s intimate with your blood supply, you should be careful,” she said. “But the risk is low ... when you get more and more bites, your risk goes up, but I wouldn’t want people not going outside because of it.”
Kyle Jarvis can be reached at kjarvis@keenesentinel.