Three people have died in Colombia after contracting the Zika virus and developing a rare nerve disorder.
It is the first time authorities have linked the disease to causing deaths.
Scientists have said they have detected the virus in saliva for the first time - raising fears it could be spread through kissing.
Dr. Tom Frieden from the Centers for Disease Control in the US has said often Zika has no symptoms: 80% of the people that get it, don’t even know they have it.
“One out of five will have mild symptoms, rash, joint pain, fever, sometimes red eye or conjunctivitis, but usually it resolves within a few days or a week at most.”