A vaccine consisting of killed whole-cell V. cholerae O1 in combination with a recombinant B-subunit of cholera toxin (WC/rBS) has been marketed since the early 1990s. This killed vaccine is well tolerated and confers high-level (85– 90%) protection for 6 months after the second immunization in all vaccinees aged more than 2 years. Three years after immunization the level of protection is still about 50% in vaccinees who were 5 years or older at the time of vaccination.
Primary immunization consists of two oral doses 7–14 days apart for adults and children aged 6 years and over. For children aged 2–5 years, three doses are recommended. Intake of food and drinks should be avoided 1 hour before 6 and after vaccination. If the second dose is delayed for more than 6 weeks, vaccination should be restarted. Following primary immunization, protection against cholera may be expected after about 1 week. Booster doses are recommended after 2 years for adults and children aged 6 years or more, and every 6 months for children aged 2–5 years. The vaccine is not licensed for individuals under 2 years of age.
In studies of travellers to countries or areas reporting cholera outbreaks, WC/rBS was found to induce approximately 50% short-term protection also against diarrhoea caused by enterotoxigenic Escherichia coli (ETEC). Two closely related bivalent oral cholera vaccines are available in India and Viet Nam. These killed whole-cell vaccines are based on V. cholerae serogroups O1 and O139 and do not contain the toxin B-subunit. These vaccines are reported to be safe and efficacious, providing 66–67% protection for at least two years against clinically significant cholera in countries or areas reporting outbreaks.
Type of vaccine:
- Killed oral O1 with whole-cell with Bsubunit
- Killed oral O1 and O139
Number of doses:
- Two doses (minimum 1 week and maximum 6 weeks apart). Three doses for children aged 2–5 years (minimum 1 week and maximum 6 weeks apart)
- Two doses 14 days apart for individuals aged ≥1 year. One booster dose is recommended after 2 years
Contraindications: Hypersensitivity to previous dose
Adverse reactions: Mild gastrointestinal disturbances
Before departure: 2 weeks
Consider for: Travellers at high risk (e.g. emergency/ relief workers)
Special precautions: None