ABSTRACT
ABSTRACT M. pneumoniae, C. pneumoniae, and Legionella species are the most important causes of "atypical" pneumonia, excluding early childhood where respiratory viruses predominate. This chapter will therefore focus on the role of these agents in respiratory tract infections. After presenting the emerging epidemiology of these agents in children and adults, an up-to-date general description of each will be followed by a discussion of recent developments in the literature for these agents. For M. pneumoniae and C. pneumoniae, the growing association with wheezing and asthma will be focused upon. For Legionella species, as current developments are many, a wide array of recent information on this pathogen will be presented.
