Epidemiologic and clinical characteristics of community-acquired invasive bacterial infections in children aged 2-29 months in the Gambia

Background: The incidence of community-acquired bacteremia (CAB) in Africa is several-fold higher than in industrialized countries. We report here the incidence of invasive bacterial infections in rural Gambia and compare the clinical characteristics of children with pneumococcal infection with those of children with extraintestinal nontyphoidal salmonella infection (NTS) or other bacterial infections. Methods: As part of a pneumococcal conjugate vaccine trial, we investigated children aged 2-29 months who presented with signs suggestive of invasive bacterial infections. Results: The incidence of invasive bacterial infections in all subjects was 1009 (95% CI, 903-1124) cases per 100,000 person-years. It was 1108 (95% CI, 953-1282) among children who had not received pneumococcal conjugate vaccine. Incidence decreased with increasing age but remained relatively high in 24- to 29-month-olds for pneumococcal infections. Pneumococcal infection was more frequent than NTS infections in the hot dry season. Respiratory symptoms and signs, consolidation on chest radiograph, and a primary diagnosis of pneumonia were more frequent in children with pneumococcal infection than in those with NTS or other infections. Diarrhea, laboratory evidence of malaria infection, and a primary diagnosis of malaria were more common in children with NTS infections. Conclusions: Bacterial infections continue to cause significant morbidity in rural Africa. Although vaccines could greatly reduce the pneumococcal burden, a high index of suspicion and appropriate use of antimicrobials are needed to manage other causes of invasive bacterial infections.