Antibiotic resistance patterns of coliforms isolated from six protected wetlands in the southeast of Spain.

Coliforms and thermotolerant coliforms were isolated from six protected lakes in the Antequera area of Spain in order to assess the sanitary quality of these wetlands. The thermotolerant coliform group consisted of several bacterial genera with a wide spectrum of antibiotic resistance. Resistance among Escherichia coli strains was correlated with the origin of the sample and three homogeneous groups of wetlands were distinguished. One of them, which corresponded to wetlands where faecal indicators were indigenous, exhibited no correlation between these bacteria and faecal pollution. Non-coli strains showed a similar range of antibiotic susceptibility for this group. In the other two groups a faecal pollution was detected and antibiotic resistance for E. coli strains established the origin of pollution.