respectively, satisfied the criteria for Norwalk-like
pattern. Of 54 outbreaks that satisfied the criteria for
Norwalk-like pattern, 14 were investigated for virus
etiology. Ten of these (71 per cent) yielded serologic
evidence of Norwalk-like virus infection. Norwalk-
like viruses are probably an important cause of out-
breaks of acute gastroenteritis. Investigation for Nor-
walk virus antibody in outbreaks that are clinically and
epidemiologically consistent with Norwalk-like virus
infection is likely to yield diagnostically useful results.
(Am J Public Health 1982; 72:1329-1332.)