The bacteriology of lower respiratory infections in Papua New Guinean and Australian Indigenous children

Indigenous children in Australia and children in Papua New Guinea (PNG) share a high burden of respiratory disease. In PNG the focus has been on pneumonia as a major cause of mortality. While pneumonia incidence remains high in Australian Indigenous children, improved access to better health care has resulted in reduced mortality. However, severe and recurrent pneumonia are risk factors for chronic suppurative lung disease or bronchiectasis in Australian Indigenous children. Bronchiectasis is associated with significant morbidity, and early death in adulthood. This paper includes an outline of the disease manifestations of acute and chronic lower respiratory infections. The main bacterial pathogens involved in pneumonia, bronchiolitis, bronchitis and bronchiectasis have been determined. Capsular organisms such as Streptococcus pneumoniae and Haemophilus influenzae type b are more often implicated in acute infections, while chronic infections are frequently associated with nontypeable (noncapsular) H. influenzae. Moraxella catarrhalis is more often isolated from very young children. Possible reasons for the high burden of respiratory disease in Papua New Guinean children and Australian Indigenous (primarily Aboriginal) children include early and dense colonization with multiple species and strains of respiratory pathogens. There is a role for vaccines in preventing lower respiratory infection.