For relent history 1918: https://history.com/news/spanish-flu-pandemic-response-citie...

- Citizens caught in public without a mask or wearing it improperly were arrested, charged with “disturbing the peace” and fined $5.

- In his book, Jacobs says that the gauze masks city officials claimed were “99 percent proof against influenza” were in reality hardly effective at all. San Francisco’s relatively low infection rates in October were probably due to well-organized campaigns to quarantine all naval installations before the flu arrived, plus early efforts to close schools, ban social gatherings and close all places of “public amusement.”

- On November 21, a whistle blast signaled that San Franciscans could finally take off their masks and the San Francisco Chronicle described “sidewalks and runnels… strewn with the relics of a tortuous month.”

... Believing masks were what saved them the first time, businesses and theater owners fought back against public gathering orders. As a result, San Francisco ended up suffering some of the highest death rates from Spanish flu nationwide. The 2007 analysis found that if San Francisco had kept all of its anti-flu protections in place through the spring of 1919, it could have reduced deaths by 90 percent.

As to discrimination based on heath issues: https://en.wikipedia.org/wiki/Mary_Mallon