Abstract

Streptococcus pneumoniae and Haemophilus influenzae are the two main pathogens responsible for bacterial respiratory tract infections. Their antimicrobial susceptibility to antibiotics like beta-lactams, macrolides or fluoroquinolones has been largely studied, while it remains less known to other antibiotics like thiamphenicol, erythromycin, cotrimoxazole or tetracycline, often used in developing countries due to their availability. In this study, the activity of chloramphenicol and thiamphenicol on different respiratory tract pathogens was found to be equivalent. However, thiamphenicol was better in detecting resistant organisms. One hundred S. pneumoniae among which 69% had reduced susceptibility to penicillin (PRSP) and 87 H. influenzae isolates, 39.1% producing beta-lactamase, were recovered from sputum cultures in children. All H. influenzae and all penicillin susceptible S. pneumoniae strains were sensitive to thiamphenicol. Susceptibility of penicillin sensitive S. pneumoniae to erythromycin, cotrimoxazole and tetracycline was 70.9%, 83.9%, and 90.3% respectively. Susceptibility of PRSP to thiamphenicol, erythromycin, cotrimoxazole and tetracycline was 68.1%, 7.2%, 17.4% and 44.9% respectively. Thiamphenicol and chloramphenicol are still active against respiratory pathogens.