The mosquito-born Zika virus may infect up to four million people, the World Health Organization said, as the agency convened to decide if the outbreak should be declared an international health emergency. Dr Margaret Chan, WHO director-general, said in a statement on Thursday that the level of alarm was “extremely high”.
“Last year, the virus was detected in the Americas, where it is now spreading explosively. As of today, cases have been reported in 23 countries and territories in the region,” Dr Chan said. “Arrival of the virus in some places has been associated with a steep increase in the birth of babies with abnormally small heads and in cases of Guillain-Barre syndrome.” The syndrome can cause temporary paralysis.
Meanwhile, Marcos Espinal, an infectious disease expert at the WHO’s Americas regional office, said: “We can expect three to four million cases of Zika virus disease.” He gave no time frame, the Reuters news agency reported. Dr Chan said a causal relationship between Zika virus infection and birth malformations and neurological syndromes was not yet established, but was “strongly suspected”.
She said the emergency committee would advise her on Monday in Geneva on the appropriate level of international concern and on recommended measures that should be undertaken in affected countries and elsewhere. Dr Chan will also ask the committee to prioritise areas where research is most urgently needed.