Characterisation of an epidemic strain of Klebsiella and its variants by computer analysis.

An outbreak of hospital-acquired klebsiella infection was investigated by means of six different typing schemes. Interpretation of the information generated by these schemes proved difficult and allowed only tentative conclusions to be reached concerning the origin of some strains. Consequently, the results were subjected to computer analysis by means of a numerical taxonomic programme adapted for the purpose. A dendrogram was constructed giving the percentage similarity between strains. It established the source of four atypical strains and showed that three of them were derived from the original clone. This form of numerical epidemiological analysis could have useful applications in the investigation of hospital-acquired infection.