Pinterest says it will try to combat misinformation about vaccines by showing only information from health organisations when people search.
Social media sites have been trying to combat the spread of misinformation about vaccines. Pinterest previously tried blocking all searches for vaccines with mixed results.
Now it says searches for "measles," ''vaccine safety" and related terms will bring up results from such groups as the World Health Organization, the Centre for Disease Control and Prevention, the American Academy of Pediatrics and the WHO-established Vaccine Safety Net.
Pinterest won't show ads or other users' posts, as they may contain misinformation.
Measles outbreaks have spiked in the US this year to its highest number in more than 25 years. Health officials worry that misinformation on social media is contributing to the spike.