A group of scientists has discovered that the Zika virus infects cells that form the cerebral cortex and interferes with its growth, an important indication but not yet scientific proof of its possible link with microcephaly, according to a study published in the learned journal Cell Stem Cell.

The research found that Zika infects laboratory-cultivated cortical neural progenitor cells equivalent to those that form the cortex during the development of the human brain, though that does not provide answers about what happens in the developing fetus or if it really causes a microcephalic baby to be born with that abnormally small head.

These discoveries are perhaps related only to the disruption of cerebral development, though it now seems more likely that proof of a direct link between Zika and microcephaly will emerge in further clinical studies, the authors say.

Cortical neural progenitor cells used in the lab research were seen to be infected just three days after being exposed to Zika and quickly began turning out new copies of the virus, which could indicate that any treatment applied will come up against some tough resistance.

The virus directly disrupted cell growth and function, while some cells died after being infected.

"We're literally the first people in the world to know this, to know that this virus can infect these very important cells and interfere with their function," Hengli Tang, one of the chief authors of the study and a biological science professor at Florida State University, said in a statement.

The time it took to make the study, just one month, shows the scientific community's sense of urgency in finding an answer to the pressing question about Zika: What is its possible link to microcephaly (babies born with abnormally small heads) and the Guillain-Barre syndrome, a neurological disorder?

The study was also directed by Guo-Li Ming and Hongjun Song, both from Johns Hopkins University.

Only Brazil and French Polynesia have reported cases of microcephaly presumably related to Zika.

Cases of Guillain-Barre syndrome with suspected links to the virus have been detected in Brazil, French Polynesia, El Salvador, Colombia, Venezuela and Suriname.