This digitally-colorized image shows particles of Zika virus, which is a member of the family Flaviviridae.
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Besides Brazil, C. quinquefasciatus also exists in more temperate climes, including the southern USA, where it is known to carry the West Nile virus and can survive winters. And knowing the mechanism of the virus could eventually allow researchers to design strategies to prevent the Zika virus from infecting different types of cells in the brain, Stern added.
Suspicions that the Zika virus is behind the apparent surge in microcephaly have been growing ever since a year ago, when maternity wards in Brazil began reporting an unusual number of cases of the disorder. Contra Costa County has reported two cases, with San Francisco and Napa counties reporting one each. But it has been linked to babies in hard-hit Brazil being born with abnormally small heads.
The deputy chief of the World Health Organization, Bruce Aylward, said the study from the medical journal Lancet which focused on a small sample of people in French Polynesia provided compelling evidence that Zika triggers the syndrome.
There were fresh signs on Friday of Zika-linked microcephaly cases outside Brazil.
The Zika virus has reached epidemic proportions in many parts of South America, prompting USA officials to issue travel advisories.
Researchers used a stem cell model to determine the Zika virus’ effect on developing fetuses and found that the infection does indeed affect cells critical for brain development, either killing them or interrupting normal function. Those ultrasounds found abnormalities in 12 of the infected women, or 29 percent. Two babies were stillborn, at 36 and 38 weeks.
Zika, which is spreading rapidly in the Americas, is usually no more harmful than a bad cold or mild flu, but global anxiety about the mosquito-borne virus has been driven by its probable link to microcephaly and GBS.
“We would like to see whether we can find ways to block the Zika entry or the action of the Zika virus on the cells”, Ming said.
While the researchers said their work does not prove conclusively that Zika causes microcephaly, they said it is an important step toward that goal.
Zhexing Wen, one of the researchers at Johns Hopkins, said the virus has an affinity for attacking neural progenitor cells as opposed to other cells.
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Tang said he is collaborating with other labs to look for substances that will block Zika infection of cells, in hopes of eventually creating a treatment for pregnant women that reduces the risk of passing the infection to their babies.
