Names on a list mean nothing until you know what you are protecting yourself from and how long it takes. Lead times are the fastest schedule the service lists, so treat them as the earliest you can be ready, not as a target.
Tetanus
The one almost everybody already has. It sits in the routine schedule at home, and it is the entry that shows up under most travellers for nearly every country on this page.
- Schedule
- A single booster if your last dose was more than ten years ago.
- Lasts
- 10 years
- Start at least
- Can be done last minute
Through dirt in a wound. A graze on a scooter, a cut on coral, a scrape off a temple step.
Hepatitis A
A liver infection that leaves you genuinely, flatteningly ill, and recovery can drag on for months. This is the one that ends trips.
- Schedule
- Two doses, six to twelve months apart. The second can easily happen after you get home.
- Lasts
- At least 25 years after the full course, and probably for life
- Start at least
- 2 weeks ahead Our estimate: the service does not publish a lead time for this one.
Contaminated food and water, and hands. Door handles, taps and shared towels after someone else washed badly.
Typhoid
A salmonella that gives you gut trouble and a fever that climbs slowly over days rather than hitting you at once.
- Schedule
- One injection, or three capsules on days 0, 2 and 4 if you take the oral version.
- Lasts
- 3 years
- Start at least
- 2 weeks ahead Our estimate: the service does not publish a lead time for this one.
Food and water again. Raw shellfish, unpasteurised milk, salad washed in the wrong water.
Hepatitis B
Another liver infection, but this one settles in for good in roughly one in ten adults who catch it.
- Schedule
- Three doses. There is an accelerated course that fits inside 21 days, with a fourth a year later.
- Lasts
- Essentially lifelong
- Start at least
- 3 weeks ahead
Blood and sex, which means tattoos, piercings, a dentist, a hospital visit and a razor at the barber all count.
Rabies
Once symptoms start it is almost always fatal. That sounds dramatic until you realise how many travellers get scratched by a monkey and shrug it off.
- Schedule
- Three doses over 21 to 28 days, or an accelerated course on days 0, 3 and 7 with a booster a year later.
- Lasts
- Long lasting, but a bite still means hospital either way
- Start at least
- 2 weeks ahead
Saliva from an infected mammal. A bite, a scratch, or a lick over broken skin. Dogs, monkeys, cats, bats.
Japanese encephalitis
A virus that occasionally causes brain inflammation. Most people who catch it never notice. The small number who do get very ill indeed.
- Schedule
- Two doses 28 days apart, or a licensed accelerated course seven days apart for adults, finished at least a week before you go.
- Lasts
- About 2 years, or 10 with the booster
- Start at least
- 2 weeks ahead
Mosquitoes that bite around dusk near rice paddies and pig farms, so it is a countryside risk rather than a city one.
Measles (MMR)
Still circulating across Asia, and about as contagious as anything gets. If you were born in a gap year for measles vaccination, check.
- Schedule
- Two doses a month apart if you have never had them. Most people only need to check their records.
- Lasts
- Lifelong
- Start at least
- 4 weeks ahead Our estimate: the service does not publish a lead time for this one.
Through the air. Crowded hostel dorms, sleeper buses, night markets.
Tuberculosis (BCG)
A bacterial infection that usually settles in the lungs. You notice nothing when you catch it, and roughly one in ten people develop the disease later.
- Schedule
- Mostly aimed at under sixteens staying three months or more, and at people working in healthcare.
- Lasts
- Decided case by case
- Start at least
- 6 weeks ahead Our estimate: the service does not publish a lead time for this one.
Coughing in badly ventilated rooms, so it takes long, close contact rather than a passing visit.
Cholera
Severe watery diarrhoea that dehydrates you fast. Rare in travellers, which is why it only appears on a few of these country lists.
- Schedule
- Two oral doses, at least one week and less than six weeks apart.
- Lasts
- 2 years
- Start at least
- 3 weeks ahead
Water and food where sanitation has broken down, typically after a flood or in a camp.
Chikungunya
Fever and joint pain that can hang around for months after the fever has gone. There are now two vaccines, both fairly new.
- Schedule
- A single dose. Which of the two vaccines you can have depends on your age and your health.
- Lasts
- Ask, the evidence is still young
- Start at least
- 2 weeks ahead Our estimate: the service does not publish a lead time for this one.
The same daytime mosquito that spreads dengue.
Dengue
Breakbone fever: high temperature and deep muscle and joint pain. There is no medicine, you ride it out.
- Schedule
- The vaccine is mainly advised for people who have had dengue before, so for most first time travellers this is a repellent question rather than a jab.
- Lasts
- Discuss it, this one is genuinely case by case
- Start at least
- 13 weeks ahead Our estimate: the service does not publish a lead time for this one.
Mosquitoes that bite in daylight, heaviest in the early morning and late afternoon, in towns as much as anywhere.
Tick borne encephalitis
A virus that can inflame the brain. Different from Lyme disease, even though the same tick carries both.
- Schedule
- Three doses, and an accelerated option where the second comes two weeks after the first. Protection is over 90 percent after the second.
- Lasts
- Booster within 3 years, then every 5
- Start at least
- 3 weeks ahead
A tick bite in forest or long grass. Unlike Lyme, the virus can pass straight over at the bite, so pulling the tick off fast does not save you here.
