JPLM: Nationwide retrospective surveillance of listeriosis in Japan, 2011-2021

Listeriosis is a major foodborne disease caused by Listeria monocytogenes, and invasive listeriosis mainly affects patients with immunosuppressive conditions with substantial mortality. Although the advance of sequencing technologies enables us to grasp the molecular epidemiology of L. monocytogenes and revealed some clones are highly associated with invasive diseases, the data outside of the European and American countries are scarce. Recent studies from the Eastern Asian countries suggests the population structures of L. monocytogenes causing human listeriosis are different from those in the European and American countries. Geographically and and economicallypolitically, Japan has strong connection to both Asian and European/American countries, the molecular epidemiology of L. monocytogenes in Japan is intriguing for investigating the international epidemiologyrelationship of the population structures of this pathogen. To investigate the clinical characteristics of human listeriosis and the genomic characteristics of the causative isolates, we conducted a nationwide genomic surveillance of human L. monocytogenes isolates in Japan, 2011-2021.