Occurrence ofClostridium botulinum in the soil of the vicinity of Rome

After the isolation of two strains ofClostridium butyricum that produced type E botulinal toxin from the feces of two babies in Rome affected by infant botulism (P. Aureli, L. Fenicia, M. Gianfranceschi, L. McCroskey, and C. Hatheway, J Infect Dis 154:207–211, 1986), extensive research was carried out to detect botulinal toxin-producing clostridia in soil samples from the vicinity of Rome. A total of 520 specimens from cultivated and pasture lands, obtained from 52 collection stations, were examined.Enrichment cultures were tested for botulinal toxin, and the isolated neurotoxigenic micro-organisms were characterized both enzymatically and gas chromatographically.Clostridium botulinum type A and B proteolytic, the former being the most common, were found in 7 (1.3%) out of 520 samples from 5 (9.6%) of the 52 locations in close association with pasture lands. Possible relationships between the presence of botulinal organisms and the properties of the soil in which they were found have also been investigated.