Published online by Cambridge University Press: 19 October 2009
In a recent paper in this Journal by Marshall et al. (1985), which described the bacterial endonuclease DNA analysis (BRENDA) of several Escherichia coli 0126 strains, the following statement was found in the summary: ‘The isolates from the outbreak produced indistinguishable DNA electrophoretic patterns in spite of their assignment to seven different H serotypes… These results support the epidemiological evidence that a single-strain outbreak had occurred, and they cast doubt on the value of H typing for this particular investigation.’ The same 0126 strains that were enterotoxigenic (ST) were treated in two earlier papers (Bettelheim & Reeve, 1982; Bettelheim, 1984) and also on these two earlier occasions the authors raised doubt about the stability of E. coliH typing results.