Nasopharyngeal Colonization by Moraxella catarrhalis and Study of Antimicrobial Susceptibility in Healthy Children from Cuban Day-Care Centers

The prevalence of nasopharyngeal carriage of Moraxella catarrhalis was determined for the first time in Cuba. One-hundred fifty healthy children attending three day-care centers in the municipality of Marianao, Havana City were studied. The percentage of recovering bacteria in nasal and pharyngeal swabs was compared. Antimicrobial susceptibilities to ampicillin, trimethoprim–sulfamethoxazole, tetracycline, cefotaxime, ceftriaxone, chloramphenicol, erythromycin, azithromycin, amoxicillin/clavulanate, and norfloxacin were determined by the disk diffusion method according to recommendations of the National Committee for Clinical Laboratory Standards. Sixty-five percent of the children studied carried Moraxella catarrhalis. The nasal cavity was the main isolation site for this organism (81% of positive cultures). Most strains were highly susceptible to the antimicrobial agents tested, except to ampicillin (53.6% resistance). This study provides evidence of the need for continued surveillance of antimicrobial susceptibility of Moraxella catarrhali, in order to determine optimal empiric therapy for community-acquired respiratory tract infections produced by this pathogen.