Zika outbreak: Florida lifts infection zone in Miami Beach

Florida declared its crisis with local transmission of Zika over for the season Friday in a welcome announcement ahead of peak tourism months, but health authorities warned that travelers would continue bringing the disease into the state.

Starting in late July, state health officials had identified four zones in the Miami area where the virus was spreading through local mosquitoes the first such transmissions in the continental U.S. and launched aggressive efforts to control the insects. One by one, the zones were deemed clear of continuing infections, and Gov. Rick Scott announced Friday that the last one - a 1.5-square-mile area in touristy South Beach also was cleared.

• Pregnant in Florida: Would you like to do a Zika test?

The beginning of South Florida's cool winter season also helped suppress the disease-carrying mosquitoes, Florida's health secretary, Dr. Celeste Philip said. But while the mosquito threat has abated, Philip noted that travelers would continue to arrive from elsewhere with the virus, and that it could still be spread between people through sexual contact.

"Hopefully by next summer we'll have a federal government that has a vaccine," said Scott, a Republican who has repeatedly criticized federal officials for an impasse over Zika funding.

Miami-Dade County Mayor Carlos Gimenez said in a statement he met this week with the director of the U.S. Centers for Disease Control and Prevention to plan for potential Zika outbreaks next year. Local officials also said residents should continue to do their part to control mosquitoes year-round in South Florida.

About 250 people have contracted Zika in Florida, and 980 more Zika infections in the state have been linked to travel, according to state health officials. Zika causes mild flu-like symptoms for most people, but it can cause severe brain-related birth defects when pregnant women become infected.

The CDC lifted a warning for pregnant women to stay out of the South Beach zone altogether, but the agency still urges them to consider postponing nonessential travel to Miami-Dade County. Zika testing is recommended for all pregnant women and their partners if they've traveled to Miami-Dade County since Aug. 1.

There have been 185 pregnant women in Florida who tested positive for the Zika virus, including women infected elsewhere, according to state health officials. Ninety-five of those women have sought treatment through the University of Miami Health System and Jackson Memorial Hospital, according to Dr. Christine Curry, an obstetrician-gynecologist and the co-director of the university's Zika Response Team.

For her patients, clearing the South Beach zone "doesn't mean they get off the hook of wearing repellent and long clothing and being cautious overall," Curry said.

Researchers say some birth defects caused by Zika infections may not be apparent at birth but develop months later.

Florida's tourism industry initially panicked when mosquitoes began spreading the disease in Miami's arty Wynwood district in July, but the state nonetheless saw record number of visitors so far this year, including to last week's art fairs in South Beach and Wynwood.

Elsewhere on Friday, researchers in Colombia said cases of microcephalywere four times higher this year than last, an increase thatcoincides with a widespread outbreak of Zika virus in thecountry.

At its peak in July, microcephaly cases in Colombia werenine times higher than in the same month in 2015, according tothe CDC's weeklyreport on death and disease.

Overall, there were 9.6 cases of microcephaly per 10,000live births in Colombia, where the virus infected as many as
20,000 pregnant women since the start of the outbreak there inOctober 2015, according to the report by researchers at the CDCand the Colombian health department.

The numbers reflect a sharp increase in rates of the rarebirth defect, proving that microcephaly was not occurringprimarily in Brazil.

"This finding confirms that countries with Zika virusoutbreaks are likely to experience large increases inmicrocephaly and other Zika-related birth defects," the CDC saidin a statement. "The report also suggests that Zika virusinfection in the first months of pregnancy poses the greatestrisk of microcephaly."

According to the report, which covers the period from August2015 through November 2016, Colombia had 476 cases of microcephaly, including 432 live-born infants and 44 thatoccurred among fetuses that did not survive the pregnancy.

The number was far lower than those in Brazil, where Zikaarrived in May 2015. As of Dec. 3, Brazil has confirmed 2,228cases of microcephaly linked with Zika, and is stillinvestigating another 3,173 cases.

Differences in Colombia

The study's authors said the difference could have resultedfrom a number of factors, including the fact that women inColombia had early warning about the risk of microcephaly.

In February, the Colombian Ministry of Health advised womento consider delaying pregnancy for six months, which may haveplayed a role. During the study period, the number of livebirths fell by about 18,000 from 2015 to 2016.

Several experts also have suggested that women in Colombiatook advantage of more permissive abortion laws, an option thatwas not available to women in Brazil, where abortion is bannedin most instances.

There were other possible differences as well, including thefact that Colombia had a higher baseline number of microcephalycases than Brazil and that 50-75 per cent of Colombians live ataltitudes above 2,000 meters, where Zika-carrying mosquitoes are not active.