Thirty-eight (designated as cases) of 60 Korean emigrants who consumed raw fresh water fish in Yangon, Myanmar developed migratory swellings and creeping eruptions on the back, abdomen, flank, and other cutaneous areas 1-10 weeks later. The symptoms included itching, nodule formation, fatigue, urticaria, fever, pain on the skin, and erythematous plaques. Skin biopsies of two cases revealed no parasites. However, the mean +/- SD peripheral blood eosinophilia among the cases was 6.3 +/- 6.5% (n = 29) and 9.0 +/- 9.8% (n = 26) in two examinations. An enzyme-linked immunosorbent assay of their serum samples, using Gnathostoma doloresi adult worms as the antigen, showed mean +/- SD optical densities of 0.47 +/- 0.29 (n = 28) and 0.32 +/- 0.20 (n = 30) in two examinations and 0.12 +/- 0.09 (n = 50) in healthy controls. Two advanced third-stage larvae of G. spinigerum were found in two of six catfish purchased at a local market in Yangon. The outbreak of the human infection is suggested to have been due to G. spinigerum, which is known to live out its life cycle in the Yangon area of Myanmar.