Global health experts agreed Wednesday to prioritise developing vaccines against the Zika virus suspected of causing birth defects, but a Brazilian specialist warned that doing so would take at least three years.
"Perhaps in three years we will have a vaccine," Jorge Kalil, head of the Butantan Institute in Sao Paulo, told reporters in Geneva, acknowledging that even that estimate was "optimistic."
Zika was previously only known to cause moderate cold and flu-like symptoms, but increasing evidence indicates the virus may be connected to multiple neurological disorders, as well as microcephaly, a severe birth defect in which babies are born with smaller heads and brains.
Experts meeting for a three-day meeting have agreed that efforts should focus on developing vaccines particularly for women of child-bearing age, as well as on creating accurate diagnostic tests and innovative vector control tools to reduce mosquito populations.
WHO's deputy director for health systems and innovation Marie-Paule Kieny told reporters that vaccine development is still at an early stage.
"It is therefore possible that vaccines may come [too] late for the current Latin American outbreak," she said, stressing though that "the development of a vaccine remains an imperative."
According to WHO, 18 companies and research institutions were already working on Zika vaccines. No vaccine has yet been tested on humans.
Over 30 labs are working on diagnostic tests, the global health body said, with a profile on the needed diagnostic tools expected to be ready by mid-April.
Zika has been linked to Guillain-Barre syndrome, another neurological disorder, but neither link has been yet proven.
Kieny also told reporters that widespread spraying to eliminate mosquitoes has failed to significantly stop the spread of dengue fever and it may be the same case for the Zika virus linked to neurological disorders.
"This is important because we must be sure that we invest in interventions that work," she said.