Emergence of antibiotic resistance in hospitals, 1935-1975.

A limited review of the changes in susceptibility of common bacterial pathogens to available antibacterial agents is presented. Significant developments in recent years include the following: (1) the emergence of Streptococcus pneumoniae with decreased resistance to penicillin and of some strains resistant to several antibiotics; (2) a decline in prevalence of multi-drug-resistant Staphylococcus aureus after 1960 following their increasing prevalence in the preceding years (these changes were methicillin-resistant (and multi-drug-resistant) S. aureus and the marked differences in their prevalence in different areas (these changes also were related to appearance of new phages in those organisms); (4) an increasing resistance to multiple drugs among enterococci but not among viridans streptococci or among nonenterococcal group D streptococci; (5) the emergence of beta-lactamase-producing Neisseria gonorrhoeae; (6) the emergence and spread of sulfonamide-resistant Neisseria meningitidis; (7) the occurrence of beta-lactamase-producing strains of Haemophilus influenzae and occasional strains resistant to chloramphenicol; (8) the focal occurrence of chloramphenicol-resistant Salmonella typhi in Vietnam and in epidemic form in Mexico; (9) the demonstration of marked differences in prevalence of resistance to multiple drugs in common pathogens to the most widely used antibiotics in different geographic areas. The dominant factor in the emergence and spread of antibiotic-resistant bacterial pathogens, whether in hospital wards or in the community, is clearly the intensive use of the antibiotic agents to which resistance emerges and then spreads.