LONDON (AP) — Facebook is adding informational labels to posts about vaccines as it expands efforts to counter COVID-19-related misinformation flourishing on its platforms.

CEO Mark Zuckerberg said in a blog post Monday that labels will contain "credible information" about the vaccines from the World Health Organization. They will be in English and five other languages, with more languages added in coming weeks.

"For example, we're adding a label on posts that discuss the safety of COVID-19 vaccines that notes COVID-19 vaccines go through tests for safety and effectiveness before they're approved," Zuckerberg said.

The social network is also adding a tool to help get users vaccinated by connecting them to information about where and when they can get their shot.

Facebook and Instagram have been criticized for allowing anti-vaccination propaganda to spread and for being woefully slow in weeding out the misinformation, often with fact-checks, labels and other restrained measures.