Acute bronchiolitis in tropical Africa: A hospital-based perspective in Ibadan, Nigeria

In a 30‐month prospective study of severe acute lower respiratory infections in hospitalized pre‐school Nigerian children, acute bronchiolitis was diagnosed in 67 cases; 19 (28.4%) and 2 (3.0%) of these had concomitant pneumonia or croup, respectively. The peak prevalence was in the wet (rainy) season (May–October). The male/female (M:F) ratio in infants ≤ 6 months was 2.9:1, differing significantly from the 1.1:1 in older subjects (P = 0.04). None of the subjects had severe malnutrition. Neither a high fever (≥ 39°C), nor tachypnea on admission was significantly correlated with co‐existing pneumonia. Of the 29 subjects in whom it was possible to explore viral immunofluorescence studies and/or serodiagnosis, we identified 26 viral identifications in 18 (62.1%) cases; 6 (20.7%) had ≥ 2 viruses. Respiratory syncytial virus was identified in 11 (38.0%) of the 29 cases, and parainfluenza virus (PIV) types 1, 2, and 3 in 10 (34.5%). PIV type 3 accounted for 7 cases, including 3 with bacteremia. Bacterial isolates were made in 9 (21.4%) of 42 blood cultures and in the only lung aspirate; Staphylococcus epidermidis and Staphylococcus aureus accounted for 4 and 3 cases, respectively. Although bacteremia was 2.9 times more common in cases with co‐existing pneumonia or croup, the respective frequency of virus‐positive cases and that of bacteremia was not significantly different between cases with bronchiolitis alone and those with associated pneumonia or croup. No deaths were recorded, but subjects aged > 6 months had a significant shorter hospital stay than those < 6 months old (P = 0.02). Despite the limited sample size, our findings reflect the etiological importance of the paramyxoviruses and the seasonal pattern of bronchiolitis in tropical Africa. Pediatr Pulmonol. 1996; 22:236–247. © 1996 Wiley‐Liss, Inc.