Prevention of travellers' diarrhoea by oral B-subunit/whole-cell cholera vaccine

Lancet. 1991 Nov 23;338(8778):1285-9. doi: 10.1016/0140-6736(91)92590-x.


B-subunit/whole-cell cholera vaccine (BS-WC) has been shown to give Bangladeshi mothers and children only 3 months' protection against severe diarrhoea due to enterotoxigenic Escherichia coli (ETEC). Since a long-lasting effect is not necessary for protection against travellers' diarrhoea, a prospective double-blind study was conducted among tourists who went to Morocco from Finland. 307 tourists received two oral doses of BS-WC, whereas 308 controls received a placebo before departure. A research team went out with tourists and a laboratory for enteric pathogens was set up on location. A faecal specimen was taken from 100 randomly selected subjects before departure, from all travellers with diarrhoea, and routinely after return. Enteropathogenic bacteria were not isolated from any of the pre-departure specimens but were present during or after the holiday in 47% of tourists with travellers' diarrhoea, and in 14% of those without diarrhoea. BS-WC induced a 52% protection (p = 0.013) against diarrhoea caused by ETEC. The protection was better for mixed infections (65%, p = 0.016). The protective efficacy against a combination of ETEC and any other pathogen was 71% (p = 0.02), and that against ETEC plus Salmonella enterica even better at 82% (p = 0.01). Partial protection against travellers' diarrhoea is thus obtainable by active immunisation with BS-WC.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Adult
  • Cholera Toxin / administration & dosage*
  • Cholera Toxin / adverse effects
  • Cholera Vaccines / administration & dosage*
  • Cholera Vaccines / adverse effects
  • Diarrhea / microbiology
  • Diarrhea / prevention & control*
  • Feces / microbiology
  • Humans
  • Immunization Schedule
  • Peptide Fragments / administration & dosage*
  • Peptide Fragments / adverse effects
  • Pilot Projects
  • Prospective Studies
  • Time Factors
  • Travel*
  • Vaccination* / adverse effects


  • Cholera Vaccines
  • Peptide Fragments
  • cholera toxin, B subunit (50-64)
  • Cholera Toxin