Colonization with potentially pathogenic respiratory tract bacteria. A household study

A group of 235 persons (180 adults and 55 children 0-15 years old) recorded symptoms of upper respiratory tract infection daily during two three-month periods (autumn 1986 and spring 1987). Samples for culture were taken from the nasopharynx and throat once during each period. Fifteen per cent of asymptomatic subjects harboured respiratory pathogens in the nasopharynx, as did 28% of those subjects with minor respiratory tract infections and 46% of those with more severe respiratory tract infections. Of children up to seven years of age, 58% were colonized with potential respiratory pathogens, which is important to keep in mind when evaluating culture reports from young children. Adults living with young children were colonized significantly more often than other adults. Branhamella catarrhalis was the most common pathogen.