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Two years ago when babies first started being born with microcephaly because of the Zika virus, there was a huge amount of fear. Women who were infected had no idea how likely it was their babies would also be harmed. Researchers have since learned that about 94 percent of babies born to women who had Zika appear to be normal at birth. Now doctors in Washington, D.C., are trying to find out how well they really are. From member station WAMU, Selena Simmons-Duffin reports.
SELENA SIMMONS-DUFFIN, BYLINE: Yariel has just turned 1. He's a curious little guy - calm and smiley with a head full of curls. You'd have no idea that his mother had Zika when she was pregnant with him.
YARITZA MARTINEZ: (Speaking Spanish). Up, up, up.
SIMMONS-DUFFIN: At this moment, he's gazing up at his mom, Yaritza Martinez, in an exam room chair, pondering a move to stand.
MARTINEZ: Up - good job. Bravo.
SARAH MULKEY: He stood up on his own.
SIMMONS-DUFFIN: This is the highlight of a half-hour motor exam with neurologist Sarah Mulkey at Children's National Health System in Washington, D.C. He sits, crawls around, rolls over.
MULKEY: I think everything as far as his development looks normal today. His exam looks great.
SIMMONS-DUFFIN: Last spring, Yaritza Martinez had no idea that this is how her story would turn out. When she was 12-weeks pregnant, she went to the Dominican Republic to take her mom to an immigration appointment. Zika has been a big risk there. And when she got back, she felt sick.
MARTINEZ: I feel, like, a fever. And the next day, I saw the rash on all my body. And they do all the blood work. And they say, you are positive. I was scared. I really, really was scared.
SIMMONS-DUFFIN: She had good reason to be scared. When Zika infections happen early in pregnancy, the risks of significant birth defects like microcephaly, seizures, hearing problems are greatest. Martinez was referred here to the Congenital Zika Program at Children's National. They're a regional hub for Zika treatment, and they put Martinez into a study that monitored her baby's brain as it developed using MRIs of her pregnant belly.
MARTINEZ: I don't like - it was my first time with MRI. And my husband - he took my hands and, you know, tried to distract me.
SIMMONS-DUFFIN: The current recommendation for Zika is to use monthly ultrasounds to monitor the fetal brain. But researchers at Children's have found MRIs give more clarity and sometimes find problems that ultrasounds miss.
MARTINEZ: Every time, they check his brain. And they say, you see, everything comes normal - everything, everything.
SIMMONS-DUFFIN: That was encouraging, but there was still reason to be nervous. With some infections, like cytomegalovirus, babies' hearing could be normal at birth and at a year, but deafness could develop by the time they get to school. Here's Dr. Roberta DeBiasi, the director of the Zika program at Children's.
ROBERTA DEBIASI: There have been reports of babies that have a normal head size at birth. But then as they're followed for a year, they develop microcephaly.
SIMMONS-DUFFIN: If a baby makes it through their first year without microcephaly, DeBiasi says it's unlikely that any serious brain issues will show up. But there's a lot scientists have yet to learn about how Zika affects babies later in life.
DEBIASI: Will they have more subtle things? Like, is there autism? Is there learning disabilities, subtle hearing things? That we have to wait and find out.
SIMMONS-DUFFIN: The study that Yariel is part of now with Dr. Sarah Mulkey is following a group of babies - some in the U.S. and some in Colombia where Zika is much more prevalent - through their first year. Mulkey would like to take it further.
MULKEY: My goal for this would be to follow them to age 7 or 8 to really know if they're doing OK.
SIMMONS-DUFFIN: Next for Yariel...
(SOUNDBITE OF BABY COOING)
MULKEY: All right.
SIMMONS-DUFFIN: ...A birthday party, a small cake, some family...
MULKEY: So congratulations on your first birthday...
MARTINEZ: Say thank you.
MULKEY: ...And a good exam today.
MARTINEZ: Say thank you.
SIMMONS-DUFFIN: Mulkey hopes she can follow Yariel for many birthdays to come, at least until he goes to school and she can be sure he's really OK. For NPR News, I'm Selena Simmons-Duffin in Washington.
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