RESUMO
The emergence of antibiotic-resistant Streptococcus pneumoniae is an international health problem. Apart from South Africa few data on pneumococcal resistance are available for sub-Saharan Africa. This study examines the nasopharyngeal carriage and prevalence of antibiotic resistance in pneumococci isolated from 260 Zambian children aged < 6 years. Pneumococci were isolated from 71.9% of the children; the odds of carrying organisms were twice as high among children < 2 years of age compared with older children. Antibacterial resistance was found in 34.1% of the isolates; resistance to tetracycline, penicillin, sulfamethoxazole + trimethoprim, and chloramphenicol occurred in 23.0%, 14.3%, 12.7%, and 3.9% of the isolates, respectively. Only 4% of the isolates were resistant to three drugs. High-level resistance was found in all isolates resistant to tetracycline; but only intermediate level penicillin resistance was found. A total of 11.1% of the isolates demonstrated intermediate resistance to sulfamethoxazole + trimethoprim. Children aged < 6 months were less likely to carry antibiotic-resistant organisms. Antibiotic resistance in S. pneumoniae appears to be an emerging public health problem in Zambia, and the national policy for the empirical treatment of pneumococcal meningitis and acute respiratory tract infections may need to be re-evaluated. The establishment of ongoing surveillance to monitor trends in pneumococcal resistance should be considered.
PIP: Pneumococcal pneumonia accounts for up to 25% of deaths in children under 5 years of age in sub-Saharan Africa. This study investigated the nasopharyngeal carriage rate of Streptococcus pneumoniae in a Zambian pediatric population and the prevalence of antibiotic resistance. Enrolled were 260 children under 6 years of age (mean age, 20 months) treated at the University Teaching Hospital in Lusaka, Zambia, in 1994. S. pneumoniae was isolated from the nasopharynx of 187 children (71.9%). The odds of carrying pneumococci were twice as high among children under 2 years of age (76.2%) than older children (59.7%). Overall, 83 (65.9%) of the 126 isolates available for antibiotic resistance profiles were sensitive to the drugs. Resistance to tetracycline, penicillin, sulfamethoxazole plus trimethoprim, and chloramphenicol was found in 23.0%, 14.3%, 12.7%, and 3.9%, respectively, of the isolates. The highest level of resistance was recorded in all isolates resistant to tetracycline. All but one of the multidrug-resistant isolates were serotype 14. Children under 6 months old were least likely to carry antibiotic-resistant organisms. In an anonymous questionnaire completed by 160 mothers, 38% reported they obtained antibiotics without a prescription and 49.4% acknowledged feeling dissatisfied when not given antibiotics to treat their sick child. Ongoing surveillance is recommended in Zambia to ensure that recommended treatment regimens keep pace with trends in antibiotic resistance.
