The Committee is scheduled to meet on Monday, February 1, when it will decide whether proliferation of Zika virus constitutes a public health emergency of international concern.

Zika virus has spread rapidly through the Americas. The first case of locally transmitted Zika in the region was reported in May 2015 in Brazil; by the end of the year, local health authorities had estimated that around a million suspected cases had occurred in the country.

While Zika virus itself only typically causes mild illness, the Brazilian health authorities have also reported a significant increase in numbers of cases of microcephaly, a serious neurological condition among newborn infants that is usually rare.

After identifying Zika virus infection in some of the mothers of infants with microcephaly, experts have begun to suspect there could be a causal relationship between Zika virus and birth defects and neurological disorders.

The World Health Organization (WHO) define a public health emergency of international concern as "an extraordinary event which is determined to constitute a public health risk to other States through the international spread of disease and to potentially require a coordinated international response."

Since May 2015, Zika virus has been reported to 22 other countries and territories. This rapid spread, coupled with concerns about the neonatal malformations, has raised concerns worldwide. At present, however, many health officials are unable to confirm how serious the situation is.

Research into risks of Zika virus during pregnancy is in progress

The lack of confirmation is due to the fact that concise information about the virus and its potential effects is scarce. In a press briefing on Thursday, members of the Centers for Disease Control and Prevention (CDC) explained the extent of what they know at present about Zika virus.

Dr. Anne Schuchat, the principal deputy director of the CDC, stated that laboratory tests at the organization had strongly suggested a link between Zika infection and poor pregnancy outcomes.

"We don't yet know what other outcomes might be associated with Zika infection during pregnancy, and there may be other factors in addition to Zika infection that might have increased risk to the fetus," Dr. Schuchat added. "More lab testing and other studies are in progress to learn more about the [...] risks of Zika virus infections during pregnancy."

Dr. Schuchat stressed that it is important for people to remember that the situation is rapidly changing, and that as new information concerning the virus comes to light, health organizations may need to update their advice:

"At this stage in a relatively new health threat, information evolves quickly, and we expect that the situation will continue to change as we learn more."

For now, the main advice concerns the circumstances of pregnant women. The CDC advise pregnant women to postpone travel to regions affected by the virus - these regions are detailed on their website.

While investigations into Zika virus continue, the National Institutes of Health (NIH) are looking to accelerate research into the virus, including diagnostics, therapeutics and potential vaccines.

At the CDC press briefing, Dr. Tony Fauci, director of the National Institutes for Allergy and Infectious Diseases, explained that they are interested in directing funding toward efforts that are specific to the current threat.

"In addition to accelerated research towards diagnostics, treatments, and vaccines [...] we're calling for basic research to understand Zika virus infection; its replications, its pathogens and transmission, and we are developing animal models," he stated. "We're doing study on evolution and emergence of the virus including the identification of factors that affect host range and variance."

Any developments will be shared in order to inform the global health response. It is hoped that further direction on a global level will be provided by the WHO early next week.

The decisions and recommendations of the Emergency Committee and the WHO director-general are due to be made public on the WHO's website.

Learn more about Zika virus, including what symptoms it causes and steps that can be taken to prevent transmission.