“KILL THE RATS,” declared the leaflet, which announced a 10-cent bounty for every dead rat and recommended the cage trap for best results. It was 1900, and a bubonic plague epidemic had broken out in San Francisco. As the city mobilized to control the rat population and contain the plague, government officials and doctors spread fear against another perceived carrier of disease — Chinese residents.

By 1900, the idea that “Mongolians” were uniquely susceptible to disease in general had already entrenched itself San Francisco. Chinese prostitutes were believed to be infected with a nearly untreatable strain of syphilis. In 1867, the city became the first in the country to institute so-called “ugly laws” prohibiting the “diseased, maimed, mutilated, or in any way deformed” from appearing in public view. Though these laws commonly targeted disabled people across the United States, in San Francisco they also targeted the supposedly inherently diseased Chinese, which was perhaps a factor behind the early emergence of ugly laws in the city. This racial perception informed the city’s response to the bubonic plague epidemic, and was only one outgrowth of the nativism prevalent in California’s political climate in the late 1800s and early 20th century.

Only one day after examiners discovered lymph nodes on a Chinese person’s dead body and named the plague as the probable killer, the city government enforced a quarantine with a rope cordon around Chinatown. Health inspectors went door to door disinfecting the houses and whitewashing the basements of all but the “wealthy and usually clean Chinese.” Hospital officials were permitted to “forbid the sale or donation of transportation by common carrier to Asiatics or other races particularly liable to the disease.” Chinese and Japanese people were banned from leaving the state without vaccination certificates. Authorities even proposed such drastic measures as razing Chinatown and forcibly relocating thousands of Chinese residents to a detainment camp on Angel Island. 

I came across this incident while researching the history of Chinese-Americans in the early 20th century. Strikingly, throughout the crisis, which ended in 1904, authorities remained truly invested in the idea that the plague was “an Oriental disease, peculiar to rice-eaters,” though the preponderance of white victims during a second outbreak a few years later soon disproved this assumption. All in all, it was very interesting how race, gender (in the case of syphilis), and class perceptions all contributed to determining public health policy and language.