Surveillance on bacterial dysentery in the City of Maanshan and analysis on its drug resistance

Objective The purpose of this investigation was to have a better understanding of the predominating strains of shigellae that caused dysentery in the City of Maanshan and their sensitivity to different drugs in order to provide a scientific basis for the prevention and control of the disease. Methods Serum agglutination test together with the biochemical identification with the ATB identification system and minimum inhibitory concentrations (MIC) assay was used for the identification of bacteria and drug sensitivity test on shigellae isolated from patients with diarrhea. Results Of the 452 samples from the patients, there were 67 samples found to be positive, including 48 strains of Sh. Flexneri and 19 strains of Sh. Sonnet. The 48 prevailing Sh. Flexneri strains (B group) prevalent in the City of Maanshan, including 5 strains of 1a, 2 strains of 2a,1 strain of 2b, 37 strains of 4c, 2 strains of X variant, involved 5 serological types with 1 strain unidentified. Drug sensitivity tests by MIC assay revealed that all shigellae were sensitive to ampicillin (AMC), cefalotin (CFT), cefotaxime (CTX), gentamicin (GEN), ciprofloxacin (CIP), tetracycline (TBT), rifampicin (RFA) except ampicillin (AMP) and sulfamethoxazole (SMZ). Conclusion It is seen that Sh. Flexneri 4c is the prevailing strain of shigellae in Maanshan City, at the same time the new Sh. Flexneri 4c and Sh. Sonnet should be taken seriously in the future.