The World Health Organization declared on Monday that the Zika virus outbreak spreading across Central and South America should be considered a "public health emergency of international concern."

The announcement came after an emergency meeting of 18 experts established by the WHO convened in Geneva to discuss the "explosive nature of the virus." By declaring it a "public health emergency," world governments will be able to prioritize research to fight the illness, according to Mashable.

The virus has been seen as the probable cause of a sharp increase in birth defects, including a condition known as microcephaly - abnormally small brains - as well as an uptick in adult neurological disorders such as Guillain-Barré syndrome, which can cause paralysis.

WHO Directror-General Dr. Margaret Chan said that while there was no definitive proof that the Zika virus is responsible for the birth defects, she said the level of alarm is extraordinarily high, according to the Associated Press.

Following that logic, David L. Heymann, the chair of the emergency committee, said Zika alone wouldn't constitute a public health emergency, but its association with microcephaly and neurological disorders led to the declaration.

Further adding to the problem is the fact that the explosively spreading virus has mild symptoms, with a large number of them showing no symptoms at all.

"Eighty percent of the people infected by Zika do not develop significant symptoms. A large number of people have the virus with no symptoms, so the situation is more serious than we can imagine," said Health Minister Marcelo Castro, according to Reuters.

Even with world governments seeking to find a cure for the illness, its unlikely a vaccine will be available for a couple of years. In the meantime, some countries will need to take a hands-on approach with the source of the disease, the Aedes aegypti mosquito. Brazil, for example, is mobilizing all resources and people to destroy the mosquitoes' breeding grounds.

The last time a health emergency of this scale was announced was for the Ebola outbreak, which killed more than 11,000 and has only recently concluded. This new outbreak will test the reforms the WHO put in place in the wake of the Ebola outbreak.