[Acquired antibiotic resistance in Madagascar: first evaluation].

The purpose of this study was to evaluate the incidence of acquired resistance to antibiotics in Madagascar. Testing was carried out on total of 1267 strains of medically significant bacteria isolated from specimens sent to the Pasteur Institute of Madagascar in Antananarivo between October 1997 and October 1998. Antibiograms were performed using the diffusion technique on gel media with antibiotic disks. Results were read according to the criteria of the Antibiogram Committee of the French Society of Microbiology. Preliminary findings documented a high incidence of resistance to widely available, low-price antibiotics including penicillin G and tetracycline for which 84 p. 100 and 65 p. 100 of Staphylococcus aureus respectively demonstrated resistance; tetracyclin to which 80 p. 100 of streptococcus were resistant; and ampicillin, cotrimoxazole, and phenicoles to which 60 p. 100, 60 p. 100 and 28 p. 100 of Escherichia coli respectively and 77 p. 100, 83 p. 100, and 71 p. 100 of Shigella sp. respectively were resistant. Second-line antibiotics including penicillin M, macrolides, nalidixic acid, and nitrofuranes were still relatively active, thus providing an effective alternative. Newly developed antibiotics such as fluoroquinolones and third-generation cephalosporines were highly effective but a few resistant strains were observed. Although not representative of Madagascar as a whole, the findings of this preliminary study indicate that acquired resistance must be taken into account in designing simplified decision charts for front-line laboratories, that appropriate information must be made available to health care workers, and that further testing is needed to monitor the evolution of antibiotic resistance.