موضوع 7
Bacterial resistance to antibiotics has been recognized since the first drugs were introduced for clinical use. The sulphonamides were introduced in 1935 and approximately 10 years later 20% of clinical isolates of Neisseria gonorrhoeae had become resistant.
Penicillin was first used in 1941, when less than 1 % of Staphylococcus aureus strains were resistant to its action. By 1947, 38% of hospital strains had acquired resistance and currently over 90% of S. aureus isolates are resistant to penicillin. Equally, it is well recognized that certain bacteria are unaffected by specific antibiotics. In other word, these bacteria have always been antibiotic-resistant.