Species and serovars of the genus Listeria isolated from different sources in Brazil from 1971 to 1997

RESUMO

Using phenotype techniques, characterization was made to species and serovar of 3,112 strains of Listeria, isolated from different sources of infection such as human (247-7.9 percent) and animals (239-7.6 percent), as well as from various routes of infection, including food (2,330-74.8 percent) and environmental constituents (296-9.5 percent), all coming from different regions of the country and collected during the period 1971-1997. The following species were recovered in the cultures analysed L. monocytogenes (774-24.8 percent), L. innocua (2,269-72.9 percent), L. seeligeri (37-1.1 percent), L. welshimeri (22-0.7 percent), L. grayi (9-0.2 percent), and L. ivanovii (1-0.03 percent). L. monocytogenes was represented by ten serovars, the most prevalent being 4b (352-11.3 percent), 1/2a (162-5.2 percent), and 1/2b (148-4.7 percent). The predominant serovar in L. innocua was 6a (2,093-67.2 percent). Considerations about laboratory methods for diagnosis and epidemiological aspects are presented on the basis of the results obtained.