Molecular typing reveals frequent clustering among human isolates of Listeria monocytogenes in Italy.
In Italy, the annual incidence of reported cases of listeriosis amounts in recent years (2004 to 2006) to 0.8 case per million inhabitants. Our study is a subtyping analysis by serotyping, ribotyping, and pulsed-field gel electrophoresis analysis of 44 human isolates from apparently sporadic cases of infection in the Lombardy region and in the Province of Florence, Italy, in the years 1996 to 2007. Based on the results of the different subtyping methods, 10 occasions were detected when strains of L. monocytogenes with the same subtype were isolated from more than one listeriosis case. A total of 28 (66.7%) of 44 isolates were attributed to molecular subtype clusters. Our data support the use of sensitive molecular approaches to identify and trace L. monocytogenes isolates responsible for foodborne outbreaks of human listeriosis.
Department of Sciences for Health Promotion G. D'Alessandro, University of Palermo, Via del Vespro 133, 1-90127 Palermo, Italy. diptigmi@unipa.it
Caterina
C
Mammina
Gerardo
G
Manfreda
Aurora
A
Aleo
Alessandra
A
De Cesare
Nathalie
N
Pellissier
Cristina
C
Romani
Pierluigi
P
Nicoletti
Patrizia
P
Pecile
Antonino
A
Nastasi
Mirella M
MM
Pontello
D000368:Aged; D015373:Bacterial Typing Techniques; D016000:Cluster Analysis; D006801:Humans; D016867:Immunocompromised Host; D007558:Italy / Q000453:epidemiology; D008089:Listeria monocytogenes / Q000235:genetics*; D008088:Listeriosis / Q000453:epidemiology* / Q000382:microbiology*