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Defense Mechanisms against Viruses in the Upper Respiratory Tract

Although human volunteers have been used extensively in the study of upper respiratory tract infections, the obvious limitations to such studies have lead to the search for an experimental model which has a nasal anatomic structure reasonably similar to man, i.e., relatively simple turbinates, true sinuses, and a mucociliated, acinar, respiratory epithelium. Among the mammals, only the primates fulfill these needs, for the common laboratory animals such as the mouse, rat or rabbit all have extensively branched and complicated turbinates associated with a highly developed olfactory complex. We have chosen the chick as a model for study because it meets the requisite criteria (Fig. 1) and is a convenient animal for upper respiratory study.