Yersinia Etymology

The new issue of Emerging Infectious Diseases has little piece on the etymology (origins) of the genus name Yersinia. The genus Yersinia is best known for its first member, Yersinia pestis, better known as the plague or bubonic plague. The name Yerisnia is not very old. The genus was renamed Yersinia after one of its discovers Swiss microbiologist Alexandre-Émile-John Yersin (1863-1943), from its original Pasturella, in the 1970s.

Yersin lived in the great age of the microbe hunters, young men who went out into epidemics in developing countries with the primary purpose of identifying new pathogens. Yersin did his homework studying medicine in Paris and working under Robert Koch in Germany on tuberculosis, Rene Roux on rabies and rounding out his study at the Pasteur Institute in Paris. From there he took a job with at French shipping company that would bring him experience with unknown infectious diseases in southeast Asia.

Yersin was one of the microbe hunters who converged on Hong Kong during an outbreak of plague in 1894. Within a week, he had isolated the bacterium that he believed responsible for the outbreak and named it Pasteurella pestis, presumably after the Pasteur Institute. Japanese microbiologist Shibasaburo Kitasato also isolated the same bacterium during the same outbreak of the plague. Both men rapidly published their findings; Yersin in French and Kitasato in English and Japanese. There has been some tension over who actually discovered the plague bacterium.

Yersin went on to continue his study of plague in search of a vaccine for many years. Late in his life he established a laboratory in his adopted country, Vietnam, where he completed his work on a plague antiserum. Yersin’s antisera is reputed to have cut the mortality rate from 90% to about 7%.

Later at least twelve members of the Yersinia genus were discovered. It is currently believed that Yersinia pestis evolved from Yersinia pseudotuberculosis.

Reference: “Entymologia: YersiniaEmerging Infectious Diseases, March 2010, 16 (3).