Laos reports local transmission of Zika virus


The findings, published today in the journal Cell Stem Cell, are significant because they are among the first to strongly suggest a link between Zika and microcephaly, a rare condition in which babies are born with underdeveloped brains and unusually small heads.

In the second study, published in the journal Cell Stem Cell, researchers at Johns Hopkins and elsewhere cultured several types of cells present in early fetal development, including so-called cortical neural progenitor cells, which form the cortex, the outer brain layer responsible for many higher functions.
A new study has all but proven that the Zika virus is the cause of the rash outbreak of devastating birth defects seen in Brazil and beyond.
The Centers for Disease Control issued a warning to pregnant women-stay away from areas where mosquitoes carrying the Zika virus breed. Numerous infected cells died, and others showed disruption that could limit their ability to divide and flourish.
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.
The evidence gets stronger every day that the Zika virus causes microcephaly.
But this week news reports indicated that Colombian scientists have confirmed their first cases of birth defects associated with Zika. In the last four months, authorities have recorded close to 4,000 cases in Brazil in which the mosquito-borne Zika virus may have led to microcephaly in infants.
The researchers, then, applied the Zika virus to the lab-grown brain cells and found that the virus infected and spread through a plate of these cells within a span of three days.
The abnormal results included not just microcephaly but also “intrauterine growth restrictions” and brain malformations. The researchers found when a pregnant women is infected and becomes symptomatic, there is a good chance the virus could do serious damage to her unborn baby.
Dr. Guo-li Ming of Johns Hopkins University, another lead study author, said researchers can now explore questions like how Zika infects the cells.
She cautions, however, that the study is still small and needs to be confirmed by following many more women for longer periods of time.
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.
“We’re starting to build the case epidemiologically that maternal infection with this virus is linked to poor fetal outcomes”, added Dr. Sallie Permar, a specialist in maternal-fetal infections at the Duke Human Vaccine Institute.