Background: In North America use of second-generation macrolides such as clarithromycin and azithromycin is popular due to favourable dosing and adverse event profiles. However, studies have also shown that use of second-generation macrolides promotes carriage of macrolide-resistant nasopharyngeal and oral streptococci. The present study was undertaken to characterize overall antibiotic use including macrolide antibiotics among children in British Columbia.
Methods: Population-based data from British Columbia were analysed to determine antibiotic prescribing patterns for outpatient prescriptions from 1996 to 2003. Antibiotic prescription rates per 1000 children per year were evaluated by age (0-4, 5-9, 10-14, <15 years old), sex and physician diagnosis.
Results: From 1996 to 2003, the overall BC prescription rate in children <15 years old decreased by one-third from 720 to 488 per 1000 children. The decrease in the rate of antibiotic consumption over time was seen across all age strata; however, the largest decrease (33%) was seen in children between the ages of 0-4 years. From 1996 to 2003, use of penicillins and cephalosporins decreased by 40% and 30%, respectively. This trend of decreasing antibiotic use with beta-lactams was seen in all age groups but the greatest decline was in the age group of 0-4 years (P value <0.05). During this time, macrolide use increased significantly (24%) from 102 to 126 per 1000 children (P value <0.001). This increase was seen in all age groups but again the greatest increase was seen in children of age between 0 and 4 years. Within the macrolides, use of erythromycin decreased by 72% (from 83 to 23 per 1000 children) while clarithromycin use increased by almost 3-fold (18-67 per 1000 children) and azithromycin use increased 81-fold (0.4-35 per 1000 children). In 2003, antibiotics were primarily being used for the treatment of upper respiratory tract infections, acute otitis media and bronchitis.
Conclusions: Overall antibiotic use has declined in children; however, there is increased use of macrolides which may have ramifications on macrolide-resistant streptococci, including Streptococcus pneumoniae and group A streptococci. A large proportion of antibiotic use in children is for upper respiratory tract infections and bronchitis, indications where there is a high likelihood that the aetiology is viral rather than bacterial.