| studies on the genesis of vibrio cholerae o139: identification of probable progenitor strains. | four lines of evidence suggest that the recent outbreak strains of vibrio cholerae o139 could have emerged from serogroup o1 strains typified by isolates m01 and m0477 described in this paper, which are neither truly classical nor truly e1 tor in their biotype attributes. firstly, like all o139 isolates, these o1 strains, isolated in madras during and before the o139 outbreak, were resistant not only to polymyxin b but also to all biotype-specific choleraphages, i.e. classical phage phi 149 and ... | 1995 | 7739019 |