Changing Pattern of Human Listeriosis, England and Wales, 2001–2004

摘要

Microbiologic and epidemiologic data on 1,933 casesof human listeriosis reported in England and Wales from1990 to 2004 were reviewed. A substantial increase in inci-dence occurred from 2001 to 2004. Ten clusters (60 cases),likely to represent common-source outbreaks, were detect-ed. However, these clusters did not account for the upsurgein incidence, which occurred sporadically, predominantly inpatients >60 years of age with bacteremia and which wasindependent of sex; regional, seasonal, ethnic, or socioe-conomic differences; underlying conditions; or Listeriamonocytogenes subtype. The reasons for the increase arenot known, but since multiple L. monocytogenes strainswere responsible, this upsurge is unlikely to be due to acommon-source outbreak. In the absence of risk factors forlisteriosis in this emerging at-risk sector of the population,dietary advice on avoiding high-risk foods should be provid-ed routinely to the elderly and immunocompromised, notjust to pregnant women