Secular trends in incidence and antimicrobial resistance among clinical isolates of salmonella at a university hospital in Taiwan, 1983-1999

The incidence and antimicrobial resistance among clinical isolates of salmo nella at a university hospital in Taiwan between 1983 and 1999 are summariz ed in this report. A total of 7986 isolates were analysed. Serogroup B has been the most prevalent over the years, with an apparently continuous decli ne after 1995. Concordant decrease was also found among S. choleraesuis and S. typhi isolates in recent years. In contrast, the proportion of serogrou p D strains increased significantly after 1996. S. typhi remained relativel y susceptible to most of the antimicrobial agents examined. For non-typhoid al isolates, antimicrobial resistance to ampicillin (62%), chloramphenicol (67%), and sulfamethoxazole-trimethoprim (37%) was relatively higher than t hat reported elsewhere. Newer generation cephalosporins and fluoroquinolone s remained effective over the years, although emerging resistance to these drugs has been noticed since 1992. A more prudent selection and use of anti microbial agents, in both humans and animals, and a continuous surveillance of resistance are essential in the future.