Importantly, he said, it also describes the type of developmental damage that would be expected to give rise to the abnormalities seen in the Brazilian imaging – small brains, with expanded fluid-filled gaps, and areas of calcification indicating dead cells, as well as an unusually smooth cortex.
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She told the BBC News website: “The effect they see could well explain the surge in microcephaly and it opens the door for many further studies into how the virus is affecting stem cells and whether this affects their ability to generate neurons in the developing brain”. But they come as separate laboratory research released Friday strengthens the case that Zika causes a serious birth defect called microcephaly – babies born with abnormally small heads – by targeting embryonic brain cells.
Infected cortical neural progenitor cells were unable to divide normally and died more often, the researchers found. The number of viable cells decreased 72 hours after infection, compared with those not infected with the Zika virus.
San Francisco health officials said the transmission of the disease is not occurring in the US, but USA health officials are warning people, especially pregnant women, to consider delaying travel plans to countries where transmission is occurring.
The World Health Organization has sent a team to Colombia to investigate the link between Zika and microcephaly in roughly 5,000 pregnant women, according to the New York Times.
He said: “Since the public health emergency of worldwide concern was declared back in February, the evidence that there may be a causal relationship has continued to accumulate”. They injected 200 Culex mosquitoes with rabbit blood infected with the virus, but the researchers don’t know if infected Culex mosquitoes already exist.
The new work provides experimental evidence that once the virus reaches the developing brain, it can infect and harm cells that are key for further brain development, said Hengli Tang of Florida State University, a lead author of the work.
They also discovered that those infected cells replicate the Zika virus, posing potential treatment problems, and that the virus is directly interfering with cell growth and function.
For the study, two labs at Hopkins produced the specialized stem cells that could grow into brain tissue.
Researchers did not take the brain cells from embryos; they created them from stem cells obtained from other sources.
Researchers also found that infected cells pump out more virus.
The research was carried out by scientists at Johns Hopkins University School of Medicine, Florida State University and Emory University.
Google said in a blog post that it is in a good position to assist since its mission is to help people find information, and it has experience analyzing large sets of data.
The findings are the first concrete evidence of a link between the mosquito-borne virus and microcephaly, which until now had been circumstantial, said Guo-li Ming, a professor of neurology at Johns Hopkins’ Institute for Cell Engineering, and a co-leader of the research.
Some of the abnormalities noted have not been reported in connection with the virus.
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Those travelling to areas where the virus has been recorded are advised to wear long-sleeves and long clothes to prevent mosquito bites, use topical mosquito repellents, and stay in cool, air-conditioned areas indoors.
