WASHINGTON — The District of Columbia's swampy past no doubt played a role in the Washington area's No. 3 rank on a list of Top Mosquito Cities released earlier this week.
The 50-city list from pest-control company Orkin doesn't actually count the number of mosquitoes in each area, but in a way it factors in the blood-sucking insect's bites. It ranks metro areas by the number of Orkin mosquito customers served from April 1, 2018, to March 31 of this year, and Washington moved up one spot from 2018.
“Mosquitoes are more than annoying. They can be a major health threat,” said Mark Beavers, an Orkin entomologist.
Worldwide, nearly 1 million people die each year of malaria, the leading mosquito-borne disease, according to UNICEF.
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In the United States, West Nile virus was the most common mosquito-borne disease with more than 2,500 cases last year nationwide. The District of Columbia had 13 cases; Maryland, 45; Virginia, 47; and West Virginia, one, according to the federal Centers for Disease Control and Prevention.
Though most people who get mosquito bites and contract West Nile virus don't show symptoms, seven of those 47 Virginians who got the virus died, the CDC said.
Other diseases that U.S. mosquitoes transmit to humans include La Crosse encephalitis — Maryland has had three cases and Virginia eight from 2008 to 2019 — and St. Louis encephalitis, which averages seven cases annually across the country.
Animals also can get diseases from mosquito bites that can be fatal.
Instances of heartworm in pet dogs, cats and ferrets have been steadily increasing since 2001, according to the American Heartworm Society, which is sponsored by veterinary pharmaceutical companies.
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Eastern equine encephalitis can spread to both horses and humans. Both Maryland and Virginia each had a human case from 2008 to 2017, the CDC said.
On Orkin's Top 50 cities list, Atlanta earned the No. 1 spot for the sixth year in a row followed by New York City. Baltimore rose 27 spots to No. 15; Richmond, Va., rose 14 spots to No. 16; and Norfolk, Va., rose two spots to No. 21.
Now that the weather is warm, mosquitoes are stirring — and breeding. They are most active when temperatures rise above 80 degrees, Beavers said.
Mosquitoes can breed in as little as 1 inch of standing water, so be sure to clean out flower pots, gutters and bird baths so the females won't have a place to lay their eggs. Trimming shrubs also can lessen the places where adult mosquitoes like to rest.
