Previous work from our group has examined the relationship between stress and immunodepression in medical students taking National Boards, Part I, and has described a relationship between stress intrusion scores (SIS) and immunodepression.We have also shown that a high proportion of individuals with generalized anxiety disorders (GAD) and panic disorders (PD) exhibit enhanced stress intrusion (SI) and are more prone to upper respiratory infections (URI). In the present preliminary study, we sought to establish a model to evaluate further the role of SI level on the extent of immunodepression. This would serve to assess in further studies the mechanism(s) of stress-induced immunodepression, its relationship to morbidity, and the role of therapeutic interventions. In 14 GAD patients and 14 controls, we correlated the expression of interleukin-2 receptors (CD25) on T lymphocytes stimulated with anti-CD3 in short term cultures and the frequency of URI and the SIS to assess the relationships among these parameters. A decreased expression of CD25 correlates linearly with increasing SIS and with a higher number of sick days with URI. These results support our previous observations that GAD patients are more susceptible to URI. Moreover, they suggest that there may be a direct relationship between immunodepression and morbidity and between SIS and immunodepression.