The World Health Organization (WHO) should take lessons from the Ebola outbreak in Africa and “urgently” convene a meeting to tackle the Zika virus, U.S. researchers wrote in a study published in a medical journal Wednesday. There are growing concerns that the mosquito-borne infection might be associated with rare birth defects in thousands of babies in Brazil.

Lawrence O. Gostin and Daniel R. Lucey, professors at Georgetown University, feared that the spread of the Zika virus may turn into a pandemic. Their study, published in the Journal of American Medical Association, called for a meeting of the International Health Regulations' Emergency Committee over the spread of Zika virus.

The first outbreak of the virus, spread by mosquitoes of the Aedes genus, was recorded in Uganda in 1947. Until recently, it was limited to a handful of countries in equatorial Africa and Asia and first appeared in Brazil last May. Since then, an estimated 1.5 million people are believed to have been infected worldwide.

"The critical lesson learned from the WHO's handling of the Ebola crises was the need for early and decisive action," Gostin, co-author of the study, said in a statement. "Yet WHO, and even advanced countries like the United States, were caught off guard. It would be unconscionable if a lack of preparedness resulted in hundreds of unnecessary cases of Zika and potential congenital abnormalities in newborns," Gostin added.

Lucey and Gostin noted that convening the committee would draw international attention, funding and research. "While Brazil, the Pan American Health Organization, and the Centers for Disease Control and Prevention have acted rapidly, WHO headquarters has thus far not been sufficiently proactive given potentially serious ramifications," the two academics said.

The Georgetown University professors also suggested to WHO that the mosquitoes should be controlled, and said that the use of insecticides and removing mosquitoes' breeding grounds would reduce the number of Zika cases. Furthermore, WHO should step up efforts to find a vaccine for the virus, they recommended.

Meanwhile, researchers at the University of Texas are attempting to create a vaccine for Zika, according to BBC. The researchers, who visited Brazil for their study, collected samples and are analyzing them in high-security laboratories in Galveston, Texas amid tight security provided by the FBI, the report added.

The Aedes genus of mosquitoes is the same carrier that is responsible for dengue fever, and is found across most continents, including South America, Africa, Asia and Oceania. Although Zika infections usually cause mild symptoms such as fever, rash, joint pain and conjunctivitis, or no symptoms at all, health officials in Brazil are concerned because the latest outbreak has corresponded with a sudden increase in the rate of microcephaly, a birth defect in which babies are born with small heads and undeveloped brains.

While an exact correlation between Zika infections and microcephaly is still not known, Brazilian officials believe that pregnant women bitten by infected mosquitoes may be transmitting the virus to their fetuses. The officials said they were investigating over 3,500 cases of microcephaly in newborns, reported since October 2015.