Reflections on pneumonia in the tropics.

This review of pneumonia in the tropics is based on experience with respiratory infectons in Papua New Guinea since the 1970s. It discusses ideas, principles, historical aspects of pneumonia research and the need to work with people in the community. In order to understand pneumonia in a tropical setng and evaluate new interventons it is essental to study the ecosystem of the causatve infectons, within the host and the community and between interactng microorganisms. Vaccines are much-needed preventve tools, and for pneumonia in a highly endemic setng the preventon of severe and fatal disease takes priority over the preventon of infecton. In this setng mild infecton plays an important role in preventng severe disease. For achieving long-term sustainable outcomes, sometmes 'less is more'. A multpronged approach is required to control and prevent pneumonia, and in devising new ways of doing so. This includes appropriate and accessible clinical care, a clean, smoke-free environment, good nutriton and a range of vaccines. Also required are persistent advocacy from the global scientfc community and strong engagement with and by the communites that bear the burden of disease. Beter health care must be pursued in conjuncton with raising literacy rates and reducing poverty.