After a century of absence, epidemic cholera has finally attacked the American continent. The outbreak started at the beginning of 1991 and has since spread with extraordinary velocity and strength. Important advances were achieved in the past year that could improve the global effort to control this dreaded disease. In contrast to the epidemic in Africa, the Latin American countries are obtaining a remarkably low case fatality rate. The strain causing the epidemic in Latin America seems to have evolved from the seventh pandemic strain with which it shares several similarities, although they are not identical. New methods for detectingVibrio choleraeand its toxin have been developed. A second enterotoxin produced byV. cholerae01 has been discovered and characterized. This might accelerate the development of better vaccine candidates and improve our understanding of the mechanisms of infectious diarrhea. As it was established more than a century ago, contamination of drinking water continues to be the most important way of transmitting this disease.