Science and Medicine
The Anti-Mask League was an organization formed in San Francisco, California, United States, to protest an ordinance which required people in that city to wear masks during the 1918 influenza pandemic. The ordinance it protested lasted less than one month before being repealed. Due to the short period of the league's existence, its exact membership is difficult to determine; however, an estimated 4,500 citizens showed up to a meeting to protest the second ordinance in January 1919.
1992–1993 Jack in the Box E. coli outbreak.
Helminthic therapy.
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