WALL STREET JOURNAL — SALVADOR, Brazil—Ana Gabriela do Prado Paschoal sat at a desk in a small medical exam room and began a familiar, heartbreaking ritual. Your baby’s head is smaller than normal, Dr. Paschoal told the anxious mother, who had contracted the Zika virus while pregnant.
The 3-month-old girl, Maria Luiza, also had lesions on her brain. Her muscles were stiffer than normal, a sign of brain damage. Maria Luiza would take longer to walk and talk, Dr. Paschoal told the mother, a 24-year-old farmworker. More serious complications were likely, but the doctor decided that was enough news for one day.
The scale and severity of prenatal damage by the Zika virus are far worse than past birth defects associated with microcephaly, a condition characterized by a small head and brain abnormalities. Scans, imaging and autopsies show that Zika eats away at the fetal brain. It shrinks or destroys lobes that control thought, vision and other basic functions. It prevents parts of the brain not yet formed from developing.
“These aren’t just microcephaly, like a slightly small head. The brain structure is very abnormal,” said Jeanne Sheffield, director of maternal-fetal medicine at the Johns Hopkins School of Medicine, who has been counseling pregnant women about microcephaly for two decades.
Microcephaly, a rare birth defect that affects about 6 out of 10,000 babies in the U.S., is often associated with developmental delays and intellectual disabilities. But some children are only mildly affected. The Zika-related cases in Brazil nearly all involve significant brain damage.
The sickest Zika babies in Brazil have died before delivery or within hours of birth. No one knows yet how long the survivors will live or how much they can be helped in the years ahead.
Brazil is now bracing for a second stage of the 6-month-old crisis: Caring for infants with a wide range of disabilities. Experts have begun calling the constellation of maladies linked to the virus Congenital Zika Syndrome—to describe the babies born with disabilities more severe than in textbook microcephaly cases. Often, liquid fills the spaces where there is no brain tissue.
“There are areas of the brain that aren’t even formed,” said Janeusa Primo Chagas, head of neuropediatrics at the hospital operated by Sister Dulce, a philanthropic organization, where Dr. Paschoal also works.
Baby Maria Luiza was one of more than 1,000 newborns since October with birth defects that are suspected of links to the mosquito-borne Zika virus. Many of the 130 infants in the care of Drs. Chagas and Paschoal may never learn to talk or walk, Dr. Chagas said. Some will have trouble seeing. Many could develop epilepsy.
“It’s safe to say almost all of them will require long-term, continual care,” said Edwin Trevathan, professor of neuroscience at Baylor University and a former director of the U.S. Centers for Disease Control and Prevention’s national center on birth defects and developmental disabilities.
Breaking the news to new mothers makes the work difficult for doctors. Mothers sometimes arrive for appointments excited because their babies’ heads have grown. Dr. Chagas has the job of telling them the change isn’t a sign of improvement, but a buildup of fluid in the head that must be drained.
Dr. Paschoal, a neuropediatric resident, often tries to soften the news, as she did with Maria Luiza’s mother, Eliane Moreira de Carvalho, because it is impossible to know the severity of the birth defects now unfolding.
Ms. Carvalho was upbeat after the consultation. “Now, we have to move forward and take care of her,” she said.
The young mother said she won’t have more children so she can concentrate her attention on Maria Luiza. Her husband also works in agriculture, and the family gets financial aid from the government to help make ends meet.
Maria Luiza has several brain abnormalities: The corpus callosum, which connects the two hemispheres of the brain and communicates between them, didn’t form properly. Her right eye could be impaired, another sign of brain damage.
“We’re careful when we talk to them because no one wants to receive this kind of news,” Dr. Paschoal said.
After seeing the first few cases last fall, Dr. Paschoal said, she wanted to cry. The 29-year-old medical resident is afraid to have her own children, she said: “I want to have them, but you don’t think about a thing like this.”
Scientists are trying to understand how a virus that has appeared benign since first identified nearly 70 years ago could now pose such a grave risk.
One possibility, they say, is that serious complications went mostly unnoticed as the virus spread from Africa to Asia and the Pacific islands. Infections might have passed largely through poor countries without effective disease tracking, or the outbreaks could have been much smaller, making complications harder to spot.