Striking differences in the nasopharyngeal flora of healthy Angolan, Brazilian and Dutch children less than 5 years old

Community-acquired pneumonia from enteric gram-negative bacilli is more com mon in developing than in industrialized countries. We investigated the nas opharyngeal flora in healthy children from Angola, Brazil and The Netherlan ds to see whether enteric gram-negative bacilli are more often part of the commensal flora in developing countries. Nasopharyngeal specimens were coll ected from children aged between 4 months and 5 years in day-care centres a nd immunization clinics. Children who had received antibiotics or were maln ourished were excluded. Brazilian and Angolan children had a higher number of household members than Dutch children (5.5 and 7 vs 3.9 mean number of h ousehold members, respectively) (p < 0.0001). Enteric and non-fermentative gram-negative bacilli were much more prevalent in Brazilian (50%) and Angol an (57%) children than in Dutch (4%) children (p < 0.0001). By univariate a nalysis, carriage of enteric gram-negative bacilli was associated with the number of household members (r = 0.26; p< 0.001). The high carriage rate of enteric gram-negative bacilli in children from Angola and Brazil may expla in why enteric gram-negative bacilli are a common cause of pneumonia in dev eloping countries.