Investigatiaons on drug-resistance of Shigella sonnei bacilli isolated in Poland in the years 1959-1972.

2538 strains of Shigella sonnei bacilli, isolated from patients in the years 1959-1972, have been tested for drug-resistance. The strains examined came from different regions of Poland. Drug-resistance has been determined by the method of "multi-arm" disks of filter-paper. In investigations 12 chemotherapeutics have been employed. The tests performed have shown that 63% of strains were resistant to one or more chemotherapeutics. The percentage of streptomycin-resistant strains, found in the investigations, was higher than that found by other authors. In the material examined 24% of strains were resistant to antibiotics, and sensitive to sulfathiazole. No strains resistant to eight or more chemotherapeutics applied have been found.