Die Verbreitung der Yersiniose beim Menschen im Großraum München unter Berücksichtigung von Schweinefleisch und Schlachtnebenprodukten als mögliche Infektionsquelle

Yersinia enterocolitica of bioserovar 4/O:3 is the most common
pathogenic type found in pigs and pork including edible offal in
Southern Germany. Limited epidemiological data is available of
human Y. enterocolitica infections in Bayern. The sources and
transmission routes of yersiniosis are not clear. This work was
conducted to get more information on the epidemiology in Munich
area. In the first part of this work, the human strains were
isolated from faecal samples of patients with diarrhoea during the
period from November 2001 to December 2002. Yersinia was isolated
from the faeces using direct culturing on selective CIN agar
plates. One typical colony per sample was identified using
EnterotubeTM. All Yersinia strains were bio- and serotyped. In all,
61 Yersinia strains were isolated from 61 patients. Fifty-eight
(95%) strains were identified as Y. enterocolitica of which 54
(93%) were belonging to pathogenic bieserovar 4/O:3, two (3%)
strains to pathogenic bioserovar 2/O:9 and two to non-pathogenic
biovar 1A. In 2002, Yersinia was found from 50 (0,21%) patients
when 22.835 faeces samples were studied. Y. enterocolitica was
identified in 48 (96%) cases. The bioserovar 4/O:3 was found in 44
(92%) patients and bioserovar 2/O:9 in two (4%) patient. Y.
enterocolitica was found in all age groups and 60% of the patients
were females. No seasonal variation was seen. Yersinia was the
third most common bacterial pathogen after Campylobacter found in
805 (3,52%) faecal samples and Salmonella found in 681 (2,98%)
samples. In the second part of this work, 36 human and 69 non-human
Yersinia strains were characterised with PFGE. The human strains
were isolated during the period from November 2001 to June 2002.
The non-human strains were isolated between 1999 and 2002. Most
(62/69) of these strains were from porcine origin. In total, 41
genotypes were obtained when the 105 strains were characterised
with PFGE using NotI, ApaI and XhoI enzymes. The Yersinia spp.
could easily be distinguished from each other with NotI enzyme.
Twenty-four genotypes were obtained when the 84 strains belonging
to bioserovar 4/O:3 was characterised with all three enzymes. Most
(90%) of the human strains were indistinguishable from the
non-human strains. These 26 indistinguishable human strains were
belonging to 8 genotypes. The non-human strains were from porcine
sources and isolated from carcasses, offal and pork. These results
demonstrate that Y. enterocolitica is frequently isolated from
patients with diarrhoea in Munich area. The most common type in
humans is the bioserovar 4/O:3, which is so far the only pathogenic
type found in pigs in Southern Germany. PFGE with NotI enzyme was
useful tool to identify Yersinia spp. Using NotI, ApaI and XhoI
enzymes, the strains of bioserovar 4/O:3 could efficiently be
subtyped. A major infection source of human yersiniosis was
revealed to be pork and edible offal.