Lymphocyte populations in acute viral gastroenteritis.

Viral gastroenteritis was induced in 16 of 24 normal volunteers after oral administration of either the Norwalk or Hawaii agents. Clinical illness lasted for 24 to 48 h and resolved spontaneously. During acute illness, a transient lymphopenia was noted which involved all lymphocyte subpopulations (thymus-and bone marrow-derived, and null cells). No circulating lymphocytotoxins were detected, and the lymphocytes remaining in the circulation responded normally to mitogenic stimuli. The acute lymphopenia occurred at the time that mononuclear cell infiltration of the jejunal mucosa has been noted. These findings are consistent with the occurrence of a redistribution of circulating lymphocytes during acute illness, with accumulation of lymphocytes at the site of infection in the gut.