Antibodies in serum and secretions 1 year after salmonella gastroenteritis.

The antibody response in serum and intestinal fluid in eight patients 1 year after their recovery from salmonella gastroenteritis was measured by solid phase radioimmunoassay and compared to the immune response within a few weeks of infection, reported previously in these and other patients. High concentrations of intestinal antibody were found in six patients compared to the concentrations found in 10 control subjects. By contrast the serum antibody concentration in the patients was only marginally higher than in the controls. The use of IgA and IgG specific antisera in the assay confirmed the presence of IgA antibody in the absence of IgG antibody in the gastrointestinal secretions, and the predominance of IgG antibody in the serum. The prolonged immune response in the gut after acute bacterial gastroenteritis supports the possibility of effective immunization against diseases entering via the gut.