ABSTRACT
This chapter describes the behavioural changes associated with upper respiratory tract infections (URTI), explains underlying mechanisms, and considers the practical implications of such effects. It also considers some early anecdotal observations that preceded the more formal research. URTIs, such as the common cold and influenza, are frequent and widespread. URTIs have a large impact on healthcare costs and are a major cause of absenteeism from work and education. The initial studies of the behavioural effects of experimentally induced URTIs have been described in a number of publications. Many upper respiratory tract illnesses have a strong resemblance to influenza but can have longer-lasting effects. Infectious mononucleosis can lead to post-viral fatigue which can persist for several months. Studying naturally occurring URTIs can be difficult because of the uncertainty of the infecting agent. URTIs influence the trigeminal nerve and compounds which increase afferent stimulation may produce changes in the brain stem.
