Dukoral
Dukoral is widely sold to travellers as protection against traveller's diarrhoea. The evidence for that use is weak, and for most people on a typical trip we will tell you it is not worth it.
Dukoral is an oral vaccine, a liquid you drink rather than an injection, and it is authorised in Canada for two things: cholera, and traveller's diarrhoea caused specifically by ETEC, one of several bacteria behind it.
That second point is where the confusion starts. Traveller's diarrhoea is not one illness with one cause. It comes from a range of bacteria, viruses and parasites, and Dukoral targets one of them. Even a vaccine that worked perfectly against ETEC would leave the rest untouched.
We would rather tell you that before you pay for it than after.
What the evidence actually shows
The Canadian Immunization Guide is direct about it. Vaccination with the cholera and traveller's diarrhoea vaccine is of limited benefit and is not routinely recommended for most travellers.
The data underneath that: pooled results from randomised controlled trials found no significant benefit for preventing an episode of traveller's diarrhoea during travel compared with placebo, at a pooled relative risk of 0.94, and no difference in effect even for the ETEC-specific illness the vaccine is designed for.
For cholera the picture is better established, at roughly two years of protection in people 6 and older and about six months in children aged 2 to under 6, beginning about a week after the primary series is finished. But cholera is genuinely rare in travellers from Canada. It is a risk for aid workers, for people working in refugee or outbreak settings, and for travellers going somewhere with an active outbreak and poor water infrastructure. It is not a risk for a resort week. For ETEC, any protection is expected to last only about three months.
When it is worth discussing
Canadian guidance leaves room for short-term travellers at high risk of complications, or of serious disruption, from traveller's diarrhoea. The reasoning is mostly about the consequences of being ill rather than the odds of it.
You cannot tolerate even a brief illness
Competitive athletes, and some business or political travellers on a trip built around one fixed event where two days out is not recoverable.
You are more susceptible than most
Low stomach acid, a previous gastrectomy, a history of repeated severe traveller's diarrhoea, or a young child over the age of 2.
You are immunosuppressed
Including HIV infection with a depressed CD4 count, or another immunodeficiency. Gastrointestinal illness carries more risk, so a marginal reduction is worth more.
You have a chronic illness that makes a gut illness riskier
Chronic renal failure, congestive heart failure, insulin-dependent diabetes or inflammatory bowel disease.
You are travelling where cholera is a real risk
Outbreak zones, humanitarian or healthcare work in affected regions, or long stays somewhere with unreliable water and sanitation. This is what it is actually a vaccine for, and that is a different conversation.
If you do take it
- 2 doses, 1 to 6 weeks apart
- At least 1 week before departure
- No more than 6 weeks
- None for 1 hour before and after
- Mixed with a buffer sachet in water and drunk
- Every 2 years for cholera, every 3 months for ETEC
- Restart the primary series
Side effects, and who should not take it
The effects most often reported in clinical trials were abdominal pain in about 16 per cent, diarrhoea in 12 per cent, nausea in 4 per cent and vomiting in 3 per cent. Notably these occurred at similar rates with the bicarbonate buffer alone, so much of it appears to come from the buffer rather than the vaccine. Anaphylaxis is very rare.
It is contraindicated if you have had anaphylaxis to a previous dose or to any component, and it should be postponed during a moderate or severe acute illness or an acute gastrointestinal illness. It has not been studied in pregnancy, so it may be considered there only in high-risk situations after weighing the benefits and risks, and it can be given while breastfeeding.
Tell the pharmacist about any antibiotics you are taking and about any other oral travel vaccines you are scheduling, so the timing can be sorted out properly rather than discovered halfway through.
Common questions
Does Dukoral prevent traveller's diarrhoea?
Not reliably. It targets ETEC, one of several causes. Pooled randomised trial data found no significant reduction in traveller's diarrhoea episodes compared with placebo, which is why the Canadian Immunization Guide says it is of limited benefit and does not routinely recommend it for most travellers.
Do I need Dukoral for Mexico or the Caribbean?
For most people on a typical resort or tourist trip, no. Food and water precautions and a rehydration plan matter more. It may be worth discussing if you are immunosuppressed, have a chronic illness that makes gastrointestinal illness riskier, or genuinely cannot afford to be ill for a couple of days.
How long before travel should I take it?
Finish the last dose at least one week before departure. The primary series is two doses given 1 to 6 weeks apart, three doses for children aged 2 to under 6, so start at least 2 to 3 weeks ahead and ideally build it into a consultation 6 weeks out.
How long does it last?
For cholera, about 2 years in people 6 and older, and about 6 months in children aged 2 to under 6. For ETEC, any protection is expected to last only around 3 months. If more than 5 years have passed since your last dose, you restart the primary series.
Can I eat before taking it?
No. Avoid food and drink for one hour before and one hour after each dose, because food and drink increase stomach acid, which can reduce how well the vaccine works.
What are the side effects?
Abdominal pain, diarrhoea, nausea and vomiting are the ones reported most in trials, and they occurred at similar rates with the buffer alone, so much of it appears to be the buffer rather than the vaccine. Anaphylaxis is very rare. Tell the pharmacist about any antibiotics or other oral travel vaccines so the timing can be planned.
Is it covered by Alberta Health?
Travel vaccines are generally not covered by Alberta Health, though many private and employer plans reimburse them. Call 403-930-5806 for current pricing before you book, and keep your receipt for your insurer.