Twitter said Monday it began tagging ?misleading? and ?disputed? claims about the coronavirus pandemic in a stepped-up effort to label potentially harmful content. The move by Twitter comes with social networks struggling to deal with a wave of misinformation and unverified claims about the disease outbreak. ?Serving the public conversation remains our overarching mission, and we?ll keep working to build tools and offer context so that people can find credible and authentic information on Twitter,? said a blog post by Twitter?s site integrity chief Yoel Roth and public policy director Nick Pickles.