Mosquitoes in two traps on Selden Island tested positive for malaria. Selden Island is a privately owned island that, while part of Montgomery County, is separated further from the Maryland shore of the Potomac River than the Virginia side.
Montgomery County began testing mosquitoes for malaria on the weekend of Sept. 28 in the northwest part of the county. Mosquito trapping and testing continues in an area that has expanded slightly.
“We’re actually coming down a bit around the McKee-Beshers Wildlife Management Area,” said Dr. Carol Garvey, chief medical officer of Montgomery County. “There actually have not been a lot of mosquitoes breeding in the Poolesville area. … They want to [test] where the mosquitoes are breeding, in the wetland areas.”
McKee-Beshers Wildlife Management Area is on River Road just north of Riley’s Lock.
ALL MOSQUITOES trapped on the Maryland shore of the Potomac tested negative for malaria, according to a county press release on Tuesday, Oct. 8. As area temperatures fall, the traps are not catching a high number of mosquitoes, said Garvey.
Testing began in Montgomery County after two mosquitoes captured in Loudoun County, Va. tested positive for the vivax strain of malaria, the least severe of the four strains of the disease. Two teenagers in Loudoun were diagnosed with malaria during the summer; neither had traveled overseas.
The incident marks the first time in over 10 years that malaria was found in a mosquito trap in conjunction with a human case.
MALARIA CASES are not uncommon to the Washington, D.C. area, but almost always involve people who have traveled abroad to countries where malaria is common. It is transmitted by infected female Anopheles mosquitoes, which feed at dusk and early in the evening.
The vivax strain of malaria can be asymptomatic, and those inflicted with it may be a source for infection. Symptoms that may occur include fever, nausea and vomiting, headache, tiredness, shaking chills, flu-like illness, diarrhea and muscle aches.
For information about malaria, call the Center for Disease Control Malaria Hotline at 404-332-4555. Or see www.mda.state.md.us/mosquito/disease.htm or www.cdc.gov/travel/other/notice_malaria.htm.