MIAMI -- Five new Zika virus cases were confirmed in Florida on Monday, including three additional infections in Miami-Dade and one more in Broward, state health officials said.
The fifth new case is a pregnant woman, but the Florida Department of Health is not identifying the county where she lives for privacy reasons. Three other pregnant women in Florida also have contracted the virus.
Florida has a total of 42 confirmed Zika cases, the health department said, including 17 in Miami-Dade and six in Broward.
Diagnosis of Zika is complicated by the fact that four out of five people infected do not show symptoms, according to the federal Centers for Disease Control and Prevention. Symptoms typically include a fever, rash, joint pain and red eyes that can last from a few days to one week.
All of the Zika virus infections were acquired by people traveling outside of the country. Of the confirmed cases in Florida, only four people are still exhibiting symptoms, state health officials said.
Pregnant women are considered to be at greatest risk from the virus because of a strongly suspected link between an outbreak of Zika in Brazil and a concurrent spike in microcephaly, a condition in which a newborn's head is smaller than expected, which can lead to developmental issues.
Florida has more confirmed Zika cases than any other state, according to the federal Centers for Disease Control and Prevention, which has reported 107 cases in the continental United States as of Feb. 24.
The number of pregnant women returning to the United States with Zika infections acquired abroad has been rising, according to the CDC. As of Feb. 17, the CDC had received reports of nine pregnant travelers with laboratory-confirmed Zika virus. Ten additional reports of Zika virus among pregnant women are currently under investigation. No Zika virus -- related hospitalizations or deaths among pregnant women were reported.