Valentina Vitoria was born in December.

She has microcephaly, the birth defect that causes an abnormally small head and can cause brain damage as well.

The baby's mother is 32-year-old Fabiane Lopes. She's caring for her daughter in a tiny, windowless one-room apartment in Rio de Janeiro. A whirring fan is the only relief they have from the heat.

In Brazil, doctors are getting closer to untangling the possible connection of Zika to microcephaly. The country has seen thousands of babies born with this birth defect since the virus arrived last year.

Lopes suspects she contracted Zika in the third month of her pregnancy, though she wasn't tested for the disease. At about 26 weeks, during an ultrasound, she was told that Valentina Vitoria was not developing normally.

"When I told my boyfriend that the baby had problems, he said he didn't want to know anything about it," she says. She remembers him saying, "You know very well what I think about that child."

She said to him, "You want her to die." And he answered yes.

Though abortion is mostly illegal in Brazil, her partner asked her to terminate the pregnancy. She refused. He walked out.

"I don't need him," she says.

Specialists say this is often how the cycle starts — some men in Brazil see a child with special needs as a woman's problem and promptly leave their partner. These mothers could then become overwhelmed and find themselves unable to cope, which is often how the children end up in state care.

Raising a child with severe disabilities is hard. Your whole life stops; you can't work, says Vera Lucia Giacometti. She is a psychologist who for 16 years has been working at a state facility for children and young adults with severe disabilities.

The parents bear a huge burden, she says. There is almost no government support.

The 38 residents in this facility, almost half of whom have microcephaly, were in most cases abandoned by their parents.

Like Carlos Felipe Alves. He's 11 years old. He was born with microcephaly. His legs are twisted beneath him, so he's unable to walk. Limb deformities often occur with microcephaly.

To be clear, there were cases of microcephaly in Brazil before the Zika virus arrived. The condition has many causes. It's unclear what was responsible for Carlos Felipe's microcephaly.

Giacometti tells me that the boy was abandoned when he was 6 and has been at the facility ever since.

I ask her what she thinks will happen with the surge in cases — thousands of children born with microcephaly since the fall compared to some 150 in a typical year.

She says simply that she believes some of these children will be abandoned and put into state care.

"I can guarantee it," she says. "I have 17 years of experience. And Brazil doesn't have the capacity to deal with what's coming."

Since the Zika outbreak, states in Brazil have reported that several microcephalic infants have been abandoned by their parents. The courts in Rio have dealt with three cases at least. There are several more in the north of the country.

But that is only a fraction of the children being born with the condition. The babies being born now with brain damage are not being abandoned en masse. Giacometti says in her experience, the children tend to be left after they are 1 or 2 years old, when it becomes harder to care for a growing child with special needs. So she expects the numbers to go up markedly in the months and years to come.

Lopes, however, is determined to care for her child.

"My daughter has a beautiful light inside her," she says. She has started a Facebook page to get donations of diapers and clothes. She has three other children who also live with her in this one room, so it's a struggle to get by. She spends most of her days going to doctors, making appointments. Valentina Vitoria has regular convulsions. Caring for the newborn leaves very little time for anything else.

For Lopes, it's the latest chapter in a life of struggle. She first got pregnant at 15 and has had seven children in all. Two live with their father and another with her mother.

Fabiane Lopes says fiercely she will never, ever give up her baby. No matter how hard the road ahead.

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