Fourth Zika Case Confirmed in Dallas County

A 55-year-old "non-pregnant" patient from DeSoto who traveled recently to El Salvador is the fourth person to test positively for infection with the Zika virus in Dallas County, the county's Health and Human Services Department said Tuesday.

Of the four Dallas cases so far confirmed by the Centers for Disease Control and Prevention, two others also have involved patients who traveled to areas where the mosquito-borne virus has spread rapidly over the past year — Honduras and Venezuela. The fourth was transmitted via sexual contact, the county health agency said.

The patient's symptoms in the case reported Tuesday have resolved. In adults, the Zika virus often produces no symptoms or a relatively mild rash, fever or joint pain, but it is suspected of contributing to a reported increase in the number of cases in Brazil of microcephaly, a birth defect that results in incomplete brain and head development for infants. Researchers also have uncovered evidence that a Zika infection might trigger Guillain-Barré syndrome, a form of temporary paralysis that has spiked in South and Central American countries where the virus has gained a foothold.

The Pan American Health Organization issued an alert regarding the first confirmed Zika virus infections in Brazil in 2015, the CDC says, and while cases of local transmission by mosquitoes have been reported in Puerto Rico, the Virgin Islands and Samoa, Zika has not found its way into the mosquito population in the states, though the growing number of imported cases could allow for the virus to spread locally in some areas in the United States.

Zika is transmitted by mosquitoes of the Aedes genus, a common pest in Dallas. This year's mild winter promises a bumper crop of mosquitoes, and Trey McCord, owner of  Mosquito Squad Of Dallas, expects the combination of more mosquitoes and worries about Zika to boost interest in his company's services.

"This is probably going to shape up to be a pretty bad year," McCord says. Mosquitoes live even in cold climates, but for Dallas, the early arrival of spring means the mosquito season is going to be that much longer. He charges customers with a 1/2-acre or less $69 per visit for a package covering a season's worth of mosquito treatments, usually about 16 between April and October. The mosquitoes never really went away this winter, though, and he said it looks like the season is already here.