“It seems like it can act on multiple fronts”.
Also on Friday, researchers in Colombia reported the country’s first cases of Zika-linked birth defects, according to the Nature science group’s news service. For instance, why are the symptoms in adults so mild?
The team studied 88 pregnant women who went to a clinic at the Oswaldo Cruz Foundation in Rio de Janeiro with the intention of being tested for the virus. Forty-two of the infected women, and all of the presumably non-infected ones, agreed to fetal ultrasound exams.
Of the 42 infected women who had ultrasounds, major fetal abnormalities were found in 12 of them – almost a third. This could lead to death of the fetus, or to the underdevelopment of the brain. “We also saw problems in the last trimester, which was surprising to us”, Nielsen reportedly said.
Six live births have occurred so far. One of the small babies and the infant with microcephaly had lesions in their eyes indicating blindness. Two other babies had normal ultrasounds and indeed, appear healthy. Another had to be delivered via C-section, because the mother’s uterus had no amniotic fluid.
But the recent study answers important questions, researchers said.
“Unfortunately, we still have many unanswered questions”, said Dr. Christopher M. Zahn of the American College of Obstetricians and Gynecologists.
The investigation testing the link between Zika virus and microcephaly was first taken up past year after Brazilian doctors noticed an increase in newborns with significantly smaller heads.
Because there is no vaccine for Zika virus, the CDC encourages people traveling to Zika-affected areas to wear EPA-registered insect repellant and practice safe sex with their partners.
In the study, the researchers derived the stem cells, called cortical neural precursors, from human induced pluripotent stem cells and found that the Zika virus easily infected these cells.
The findings, published Friday in Cell Stem Cell, detailed exposure of cells that ultimately contribute to the formation of the brain.
Besides Brazil, C. quinquefasciatus also exists in more temperate climes, including the southern US, where it is known to carry the West Nile virus and can survive winters.
These lab-grown cells might be used to screen for drugs that protect the cells, Cell Stem Cell said.
Although this is an early study, it shows the mechanism by which the virus works in certain cells, he said.
At Johns Hopkins’ Institute for Cell Engineering, part of Johns Hopkins Medicine, neuroscientists Hongjun Song and Guo-li Ming collaborated with virologist Hengli Tang at Florida State University and colleagues in a laboratory study to see if they could make the connection between the virus and the birth defect.