Google is now not allowing its advertisers to bid and place ads on face mask related keywords. Lane Rizzardini first notified me of this on Twitter by sharing a screen shot of Google Ads disallowing this in the advertising portal.
If you try to search for these keywords, I personally do not see any Google Ads show up in Google search.
Google sent Search Engine Land a statement that reads "We're committed to protecting users and surfacing helpful, authoritative information as the coronavirus situation continues to evolve," a Google spokesperson said in a statement given to Search Engine Land. "Since January, we have blocked hundreds of thousands of ads for misleading coronavirus-related products or services. Out of an abundance of caution, we have decided to temporarily ban all medical face mask ads. We’re actively monitoring the situation and will continue to take action as needed to protect users."
This can fall under the advertising guidelines as a "global health crisis."
Forum discussion at Twitter.