MIAMI _ South Florida men should not donate sperm because they are at greater risk of spreading Zika, federal health officials said this week _ advice that already had been in place for Miami-Dade, the only county in Florida with a sustained outbreak of the virus last year.
The Centers for Disease Control and Prevention expanded its guidance on Monday to include Broward and Palm Beach counties after completing an analysis with the Florida health department of locally acquired cases, including an examination of resident travel patterns in South Florida. The advice applies to men who lived or traveled in those three counties since June 15.
Federal health officials said they expanded the area for the guidance because Zika infections were reported in people in South Florida who said they had not been to Miami-Dade.
The CDC said that resident travel between the three counties and the difficulty of pinpointing where a person may have contracted Zika from a mosquito make it very likely that the virus spread well beyond the limited zones in Miami-Dade identified by Florida health officials last year.
This increased risk is especially relevant for men because there's evidence Zika can persist in semen longer than in other body fluids.
Of the 279 locally acquired Zika cases recorded in Florida for 2016, at least 259 were in Miami-Dade _ more than any other county. Miami-Dade also was the only county identified as having four zones with active spread of the virus in 2016, including in Miami Beach and Miami's Wynwood and Little River neighborhoods.
In 2017, state health officials have reported one locally acquired case of Zika, in Miami-Dade. There are also 21 travel-related infections statewide, including four in Miami-Dade, and two categorized as "undetermined" after state health officials were unable to identify where those cases originated.
Zika is spread primarily by the bite of an infected Aedes aegypti mosquito, but the virus also can be sexually transmitted and remains in semen for months, the CDC said. Most people infected with Zika do not feel symptoms, which can include fever, joint pain, red eyes and a rash.
But infection during pregnancy can lead to birth defects, including microcephaly and other neurological disorders.
