The Zika virus can inflict serious damage to several areas of a fetus’ developing brain beyond microcephaly, indicates a new study of brain scans and ultrasound pictures of 45 Brazilian babies whose mothers were infected with Zika during pregnancy .
The images also show that damage was seen in areas of the brain that continue to develop after birth, which suggests that babies born without any signs of birth defect may suffer problems as they age.
The study, published in the journal Radiology, primarily involved babies who were born with microcephaly, a medical condition in which the brain does not develop properly resulting in a smaller head. The condition can present at birth or develop during the first years of life. It is often associated with a neurological disability.
The infants in the Zika study who were born with microcephaly also had other impairments, almost all of which occur before microcephaly, since a smaller head size occurs when the brain fails to develop fully.
“The abnormalities that we see in the brain suggest a very early disruption of the brain development process,” Dr. Deborah Levine, an author of the study, told The New York Times.
The images could help doctors diagnose Zika at an even earlier stage, such as the second trimester when a woman may still have the option to terminate the pregnancy, said Dr. Adre du Plessis, director of the Fetal Medicine Institute of Children’s National Health System. Dr. du Plessis was not involved in the study.
“If there’s any uncertainty on ultrasound, we’re concerned that couples that are not risk-takers and don’t want to gamble might be terminating perfectly normal babies, which is of course a concern to us,” he said. “So there is a lot riding on being able to image accurately.”
When a fetus’ brain is infected by a virus, it often leaves deposits of calcium. These clumps of calcium in Zika-infected babies appear to be in an unusual place in the brain. If this proves to be a pattern with Zika-infected babies, it suggests that Zika targets vascular areas, which could explain why the infection is so devastating to developing fetuses.
The images suggest that Zika can cause damage to the brain in three ways – preventing the brain from forming normally, obstructing areas of the brain, and destroying areas of the brain after they form.
“It’s key to realize that Zika is more than microcephaly, that there’s a number of other abnormalities as they’ve shown in this paper, and its effects are going to be even more broad,” said Dr. Catherine Y. Spong, acting director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, who was not involved in the study.
Source: NY Times