Seashore water samples collected along the coastline in Bulgaria and Rumania contained in large numbers OK serovars of V. parahaemolyticus; some of these had been isolated repeatedly over an extended time period: 01 K32, 03 K30, 03 K48, 04 K37, 04 K53, 05 K17, 05 K30. The serovar 05 K17 was virtually present in all water samples and was also isolated from a case of purulent ear infection in a child from Burgas. In contrast, strains recovered from Asian and African coastal water had different K antigens and were never identified in Europe. Two strains of V. parahaemolyticus (serovars 05 K15 and 07 K10) had positive swarming growth resembling that of V. alginolyticus. The first of these was Kanagawa-positive and was isolated from a case of severe diarrhea in Brazzaville. Vibrio parahaemolyticus isolates came from marine or brackish water specimens collected on sand banks, 3 strains were recovered from marine or brackish water in Africa. Vibrio harveyi, a sucrose-negative species important from differential diagnostic aspects, has been isolated from seashore water samples collected on coarse-sand or pebbly beaches.