WASHINGTON, D.C.- Researchers are looking for people willing to be infected with the Zika virus.
It's part of the search for a vaccine. The study is planned for this winter, at a time when mosquitoes aren't biting.
The quest for a vaccine began less than a year ago. That's when Brazil's massive outbreak revealed that Zika can harm the brain of a fetus if a woman is infected during pregnancy.
Now, researchers in the United States have begun safety testing of two vaccine candidates. And more experimental shots are poised to undergo preliminary testing soon.
Any that seem promising will have to be tested in thousands of people in parts of Latin America and the Caribbean that are hard-hit by the mosquito-borne virus. It's the only way to prove if an experimental vaccine really protects.
Even if all goes well, a vaccine wouldn't be available for general use any time soon.