a1 Central Laboratories of the Ministry of Health, Jerusalem, Israel
a2 Department of Laboratories of the Ministry of Health, Jerusalem, Israel
a3 Faculty of Biotechnology and Food Engineering, Technion – Israel Institute of Technology, Haifa, Israel
a4 Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel
During the 11-year period from 1997 to 2007, 321 isolates of Listeria monocytogenes from sporadic cases of invasive listeriosis were reported to the national reference laboratory in Israel. Of these isolates, 113 (35%) were identified from perinatal cases, and 208 (65%) from non-perinatal cases. The prevalent serovars were 4b, 1/2b, 1/2a and 4c. Serovar 4b was identified in 80·5% of the perinatal isolates (P=0·0162), while the number of 1/2b and 1/2a strains increased in the 60 years old group (P=0·0285). Resistance to tetracycline was found in eight 4b isolates. The seasonal distribution showed that 206 isolates (64·2%) were submitted during the hot season (May–October). The estimated morbidity for the study period was 4·4 per million. The incidence of invasive listeriosis was higher in the perinatal group (5·6/100 000), than in individuals aged 60 years (1·5/100 000).
(Accepted July 02 2008)
(Online publication September 16 2008)
c1 Author for correspondence: Dr V. Vasilev, Central Laboratories of the Ministry of Health, 9 Yaakov Eliav Street, PO Box 34410, Jerusalem 91342, Israel. (Email: firstname.lastname@example.org)