Up to four million Zika cases predicted

Three to four million people could be infected with Zika virus in the Americas this year, the World Health Organization (WHO) predicts.

Most will not develop symptoms, but the virus, spread by mosquitoes, has been linked to brain defects in babies.

Meanwhile, the US says it hopes to begin human vaccine trials by the end of 2016.

Read more at: http://www.bbc.com/news/health-35427493