Isolation studies for bacterial and parasitic agents were carried out on stool specimens from Vietnamese infants at the time of their mass airlift to the United States. One or more bacterial pathogens were found in 49% of the 367 stool specimens cultured. The isolates included enteropathogenic Escherichia coli (161), Shigella (16), Salmonella (15), but no Salmonella typhi or Vibrio cholerae. Parasites identified in 88 stool specimens included Giardia lamblia (10), Ascaris lumbricoides (7), and Entamoeba histolytica (1). Transmission of agents to volunteers probably occurred, because 48% of 272 adults questioned had diarrhea shortly after caring for the children, and stool cultures from these adults resulted in the isolation of E coli (105), Salmonella (1), and Shigella (3).