Neurodegenerative disorders of the elderly, like Alzheimer's disease (AD), are an increasing health problem in our society. Despite extensive research, the exact etiology of these syndromes is still unknown and cure is lacking. Currently, growing evidence suggests that infections may be involved in the etiology of these diseases. In particular, an association between Chlamydia pneumoniae and AD has been suggested. Nevertheless, the field is still in its infancy and future studies are required to further unravel these associations.