Reports of anthrax around the first world war can apparently be linked to horsehair shaving brushes popular at the time, reports Physician’s Briefing. 

The researchers found that early outbreak summaries from 1915 to 1924 showed numerous reports of shaving brush-associated anthrax cases from the United States and England. Using anthrax surveillance data for 1919 to 1924, contaminated shaving brushes were found to account for at least 10 percent of all anthrax cases in the United States, and up to half of cases in New York City. In case reports, case series, or line lists, 43 cases of anthrax definitely or possibly associated with shaving brushes were described from 1917 to 1989. Twenty of these cases were possibly associated with use of a recently purchased shaving brush and the rest were definitely associated.

“This historical information is relevant to current public health practice because renewed interest in vintage and animal-hair shaving brushes has been seen in popular culture,” the authors write. “This information should help health care providers and public health officials answer questions on this topic.”