Characterization of human invasive isolates of Listeria monocytogenes in Sweden 1986-2007.
Since 1986, 68% of the Listeria monocytogenes isolates from human cases of invasive listeriosis in Sweden are available for retrospective studies. The aim of the present study was to characterize 601 human invasive isolates of L. monocytogenes in Sweden from 1986 to 2007 by using serotyping and pulsed-field gel electrophoresis. Since 1996, serovar 4b was permanently reduced to the second or third most common serovar in human cases in Sweden. During the latter period, 2000-2007, only 13% belonged to serovar 4b and 71% to 1/2a. The dendrogram, based on pulsovars, reveals two clusters with different serovars. Cluster 1 exhibits serovars 4b and 1/2b, whereas cluster 2 consists of serovar 1/2a. Serovar 1/2a seems to be more heterogeneous than serovar 4b.
Department of Restaurant and Culinary Arts, Orebro University, Grythyttan, Sweden.
Vishal Singh
VS
Parihar
Gloria
G
Lopez-Valladares
Marie-Louise
ML
Danielsson-Tham
Inoka
I
Peiris
Seved
S
Helmersson
Magnus
M
Unemo
Birgitta
B
Andersson
Malin
M
Arneborn
Elizabeth
E
Bannerman
Sukdevo
S
Barbuddhe
Jacques
J
Bille
Lajos
L
Hajdu
Christine
C
Jacquet
Christina
C
Johansson
Margareta
M
Löfdahl
Gunnel
G
Möllerberg
Håkan
H
Ringberg
Jocelyne
J
Rocourt
Ingela
I
Tjernberg
Jan
J
Ursing
Birgitta
B
Henriques-Normark
Wilhelm
W
Tham
D016000:Cluster Analysis; D016521:Electrophoresis, Gel, Pulsed-Field; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D006801:Humans; D008089:Listeria monocytogenes / Q000145:classification* / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology*; D010802:Phylogeny; D012189:Retrospective Studies; D012703:Serotyping; D013548:Sweden