(Editor’s note: Updated July 27 with two additional non-travel-related Zika cases from the Florida Department of Health.)
By Valarie Basheda
WebMD Health News
Health officials in Florida are investigating four Zika infections that may be the first in the U.S. from a mosquito found here.
Florida Department of Health officials announced in a brief statement July 19 they were investigating a potential case of local transmission in Miami-Dade County. On July 22, the department said it was investigating a second Zika infection in neighboring Broward County.
On Wednesday, the department said it was investigating two more Zika cases not associated with travel — an additional case in both Miami-Dade and Broward counties.
The CDC is helping with the investigation, health officials said. The department said earlier it has asked the CDC to send a medical epidemiologist to assist. Few other details were given.
If the virus was passed through a mosquito bite, the cases would be the first local transmission documented in the U.S.
All previous Zika cases have been travel-related, meaning someone got the virus in a country where Zika is spreading. Others have become infected through sexual transmission from someone who got the infection from traveling abroad.
One person in Utah, who was a caregiver to an elderly man with Zika who died, also contracted the virus, but officials don’t know how. The mosquitoes that transmit Zika are usually not found in Utah. The CDC is also investigating that case.
On Friday, The Florida Department of Health said its investigators are going door-to-door through the neighborhoods where the Zika patients live. So far, disease detectives have interviewed and tested 200 people as part of investigations into the two cases. The department said it is also waiting on additional lab results.
The department is distributing Zika prevention kits to the affected communities, and is urging residents to comply with requests for blood and urine samples so officials can determine the number of people who may be affected.
An estimated 80% of people infected with Zika don’t show symptoms. The others may have a fever, joint pain, and red eyes (known as conjunctivitis). But Zika can wreak havoc on the unborn, causing devastating birth defects including microcephaly, in which babies have unusually small heads and brain damage.
The CDC has reported more than 1,400 travel-associated cases of Zika in the continental United States and Hawaii. As of July 14, 12 babies with birth defects linked to Zika have been reported in the U.S. Six other pregnancy losses with birth defects were linked to the virus.
Aedes aegypti and Aedes albopictus mosquitoes are believed to be the carriers in the Zika outbreak spreading through the Americas.
A recent WebMD survey of 2,700 people found they are more concerned about mosquitoes this year than the past few years, mainly driven by the Zika virus. Many said they plan to take additional steps to prevent mosquito bites.
WebMD’s Brenda Goodman contributed to this report.