Matching of Antibiotic Resistance Patterns of Escherichia coli of Farm Families and Their Animals

Escherichia coli from 14 Missouri farm families and their livestock were characterized as to their patterns of resistance to antibiotics. Identical antibiograms that were found in E. coli of members of the farm family and associated groups of animals were counted as matches, using three types of counting techniques. Five hundred random assortments were made between the set of 14 farm families and the set of 14 groups of livestock. Matches were also counted when farm families were matched with their own livestock. With randomization, three of the 500 assortments yielded a value as large as the 44 matches observed when farm families were matched with their own livestock. Statistical tests indicate a strong association between the resistance patterns of the E. coli isolated from people and those isolated from their livestock.