Flores became infected early in her pregnancy, and frequent ultrasounds and bloodwork are the only comfort doctors can offer in what so far looks like an issue-free pregnancy despite Zika, which can cause shrunken heads and other problems.

Flores and her husband have gotten used to hearing their doctors respond to questions about their baby`s future with a simple sentence: "I don`t know."

"It is really hard to hear something like that. It is scary at times," Flores said Monday at Jackson Memorial Hospital in Miami, where she is being treated by the University of Miami`s Zika Response Team.

"There`s great joy, but it was very hard to bring this child into the world with this type of news," Flores said in Spanish, speaking through an interpreter. "It`s a mix of emotions."

Flores` unborn daughter — named Daniela — seems to be developing normally. That`s a relief, because Zika can cause severe brain-related birth defects when pregnant women become infected.

However, the family still faces years of uncertainty after the baby is born in February. There are no tests to determine whether Flores` child will suffer from hearing, vision or developmental problems as she grows into a toddler.

Flores` experience illustrates the gaps in doctors` understanding of how Zika affects pregnancy, said Dr. Christine Curry, Flores` obstetrician-gynecologist and the co-director of the Zika Response Team. For example, doctors don`t currently know why the virus — which is mainly spread by city-dwelling mosquitoes but also can be sexually transmitted — remains detectable in a pregnant woman`s bloodstream far longer than in the bloodstream of a man or a woman who is not pregnant.

"It`s hard to continue to say, `I don`t know,` but it`s not unexpected with a disease that`s really made its mark only in the last few years," Curry said.

Flores had not shown any Zika symptoms, but testing performed when she was 16 weeks pregnant in late August confirmed that she had been infected. Her husband also was tested for Zika, but his results were negative.

It`s not clear where Flores contracted the virus. She lives and works in Miami`s Wynwood neighborhood, the first area in the continental U.S. to have mosquitoes spread the virus, but she traveled to Honduras earlier in the summer at the beginning of her pregnancy.

Until this summer, the only cases of Zika on the U.S. mainland stemmed from travel to areas with Zika epidemics — mostly the Caribbean and Latin America. Of the more than 4,000 U.S. cases to date, nearly 900 were pregnant women.

The Miami area comprises the bulk of Florida`s Zika caseload, and U.S. health officials now recommend Zika testing for all pregnant women who have spent time anywhere in Miami-Dade County.

Over 110 women in Florida have been diagnosed with Zika, and Curry said about a third of them have been cared for by University of Miami Health System doctors at Jackson Memorial Hospital.

Like Flores, many expressed shock and sadness at their Zika diagnosis before resolving to learn more about how they could help their babies, Curry said.

Flores had some advice for other pregnant women with Zika: "First of all, have faith. Then make sure you go see your doctor, and just know that everything is going to be OK if you keep up with the recommendations from the doctors."

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