And the findings strongly support the idea that Zika, a once-obscure virus believed to cause little more than a headache and a rash, can be a killer. The department is providing area doctors, including obstetricians, up-to-date information about the virus, including questions to ask patients who may be exposed to Zika and common symptoms, microcephaly-1115772-2/?utm_source=Futurity+Today&utm_campaign=50660fb00f-March_4_20163_4_2016&utm_medium=email&utm_term=0_e34e8ee443-50660fb00f-206349089" target="_blank">said spokeswoman Lisa de Hernandez. Two were born extremely small, which means they could experience complications of low birth weight.
"Much like West Nile (virus), we'll see a classic epidemic curve, with lots of cases before it plateaus, and then cases will fall", he said.
Scientists in Brazil have shown Culex quinquefasciatus - one of 15 mosquito species found in New Zealand - is able to be infected with the virus in the lab.
However, researchers still need to figure out other aspects of how the virus works in the body, for example, "how the virus crosses the placenta and gets into the fetal brain", he told Live Science.
The USA needs to "act now as if there were a very clear causal link" between Zika and birth defects, rather than wait for iron-clad proof, said Lawrence Gostin, director of the O'Neill Institute for National and Global Health Law at Georgetown University.
And, although it might be logical to conclude from the study that the Zika virus attacks, damages and kills important cells that build the brain, Ming said they now have to "determine whether the Zika virus infection can lead to microcephaly in a different cultural model system, a three-dimensional model".
The papers, published by the New England Journal of Medicineand Cell Stem Cell, were both published online Friday, hours after the World Health Organization announced an emergency committee meeting next week to review "accumulating evidence" linking Zika with serious neurological disorders.
In this photo taken on Monday, Feb. 29, 2016, provided by Florida State University, Professor Hengli Tang confers with his graduate student and co-author Sarah Ogden about the next steps in their Zika virus research in Tang¿s lab at FSU, in Tallahassee, Fla.
In the Cell Stem Cell paper, US researchers used lab-grown human stem cells to show that Zika can infect cells that form the brain's cortex. There were two miscarriages early in the pregnancies, and two stillbirths just a few weeks before the babies were due, Nielsen-Saines says.
The Zika virus originated in Africa and residents of the Americas have no immunity against it. Brazil and French Polynesia have seen the worst increases in microcephaly. For example, it is not clear why the symptoms of a Zika infection are so mild in adults, compared to in fetuses, or how the virus enters the nervous system of the developing fetus, they said.