Planning an international trip means thinking about a lot of things — flights, accommodations, visas. Vaccines often end up at the bottom of the list. That’s a mistake.

Diseases that are rare or nonexistent in the U.S. are common in many of the world’s most popular destinations. Some countries won’t even let you cross the border without proof of certain vaccines. A quick pre-travel visit to a travel health clinic can keep you protected — and keep your trip from getting cut short.

Here are seven vaccines to have on your radar before your next international trip.

Where Can I Get Travel Vaccines?

Passport Health is the largest travel medicine provider in the United States. At any of our clinics, a travel health specialist will review your itinerary, walk you through what’s recommended for your destination, and make sure you leave with everything you need — vaccines, documentation, and answers.

Passport Health is also an authorized yellow fever vaccine provider — important if you’re headed to parts of Africa or South America where proof of vaccination is required to enter the country. The CDC and WHO recommend visiting a travel health clinic at least four weeks before you leave.

1. Yellow Fever Vaccine

Yellow fever is a mosquito-borne virus found in parts of sub-Saharan Africa and tropical South America. There’s no treatment once you have it. Vaccination is your only protection.

It’s also the one travel vaccine that comes with serious border consequences. More than 40 countries require proof of yellow fever vaccination to enter, and some require it even if you’re just passing through an affected region. That proof has to be an official International Certificate of Vaccination — the “yellow card” — issued by an authorized provider like Passport Health. A note from your doctor won’t do it.

One dose, given at least 10 days before travel, is all you need. It’s considered valid for life. If you’re traveling anywhere in sub-Saharan Africa or South America, check the entry requirements for your specific destination well before your departure date.

2. Hepatitis A Vaccine

Hepatitis A spreads through contaminated food and water and is one of the most common vaccine-preventable illnesses travelers bring home. You don’t have to seek out street food to get it — a sit-down restaurant is just as capable of being the source if sanitation standards are different from what you’re used to.

The CDC recommends it for travel to much of Asia, Africa, Central and South America, and parts of Eastern Europe. A single dose is enough to protect you for the trip — it takes effect within about two weeks. The second dose, given six to twelve months later, extends that protection long-term.

If you’re doing rural travel or staying somewhere for an extended period, make sure this is on your list before you go.

3. Typhoid Vaccine

Typhoid fever is caused by Salmonella Typhi bacteria, picked up through contaminated food or water. It’s common in South Asia, Southeast Asia, sub-Saharan Africa, and Latin America — and it can get serious quickly without treatment.

There are two vaccine options. The injectable version is a single shot given at least two weeks before travel. The oral version is four capsules taken every other day — it has to be finished at least a week before you leave, and you can’t take it alongside antibiotics. Your Passport Health specialist can help you decide which makes sense for your trip.

Type	Format	Doses	Age Range	Key Notes
Injectable (Vi polysaccharide)	Single shot	1	2 years+	Given at least 2 weeks before travel
Oral (Ty21a, live-attenuated)	Capsules	4 (every other day)	6 years+	Complete at least 1 week before departure; can’t take with antibiotics

4. Hepatitis B Vaccine

Hepatitis B is a liver infection spread through blood and body fluids. Many Americans got this vaccine as children, but the exposure risks abroad are different — and more frequent — than what most people encounter at home.

It’s recommended for travelers who might receive medical or dental care in-country, who plan to get tattoos or piercings abroad, or who are staying for an extended period in areas with high hepatitis B rates — which includes most of Asia, Africa, and parts of South America and Eastern Europe. Healthcare workers and long-term volunteers should make sure they’re covered before they leave.

The standard series is three shots over six months. If your trip is coming up sooner than that, there are accelerated schedules available.

5. Tdap (Tetanus-Diphtheria-Pertussis)

Tdap covers tetanus, diphtheria, and pertussis (whooping cough). Adults need a booster every 10 years, and a lot of people are overdue without realizing it.

Travel raises your exposure to all three. Minor cuts and wounds are common when you’re out exploring, and pertussis spreads easily in crowded places — airports, buses, group tours. If you’re not sure when your last booster was, it’s worth checking before your trip.

6. MMR (Measles, Mumps, Rubella)

Measles is rare in the U.S., but it’s still circulating in many parts of the world. Europe, Asia, Africa, and the Americas have all seen active outbreaks in recent years. The disease spreads through the air — you don’t need direct contact with someone to catch it.

If you were born after 1957, you should have two documented MMR doses. Many adults only received one as a child and may not have full protection. A second dose is safe even if you’re already immune, so if your records are unclear, go ahead and get it.

Traveling with an infant? The MMR vaccine can be given as early as 6 months for babies heading into high-risk areas. That early dose won’t count toward their routine schedule, but it will cover them for the trip.

7. Polio Vaccine

Most Americans think of polio as a solved problem. In the U.S., it is — the disease was declared eradicated here in 1979. But wild poliovirus still circulates in parts of Pakistan and Afghanistan, and vaccine-derived poliovirus outbreaks have been reported in Africa, the Middle East, and Southeast Asia — including in countries that see significant tourist traffic.

If you completed your childhood polio series and are now traveling to an at-risk region, you should receive a one-time adult booster of IPV (inactivated polio vaccine). Some countries, including Saudi Arabia for Hajj pilgrims, require proof of polio vaccination for entry.

This is one of the most commonly overlooked travel vaccines because it feels like ancient history. For anyone heading to endemic or outbreak-affected areas, it isn’t.

Which Seasonal Vaccines Do Travelers Need?

In addition to the seven vaccines above, there are three seasonal vaccines worth checking before any international trip. These don’t fit neatly into the “travel vaccine” category, but they matter for travelers.

Do I Need a COVID-19 Booster Before International Travel?

COVID-19 continues to circulate globally. An illness abroad — even a moderate one — can mean missed flights, unexpected medical costs, and a ruined trip. Updated boosters for the 2025–2026 season are available from Pfizer (COMIRNATY, ages 5+), Moderna (SPIKEVAX, ages 6 months+), and Novavax (NUVAXOVID, ages 12+). The CDC recommends staying current for everyone 6 months and older.

Should I Get a Flu Shot Before Traveling Abroad?

Flu season runs on a different calendar outside the U.S. In the Southern Hemisphere, peak season is April through September — which means a traveler heading to South America or Australia in June is walking into flu season, not away from it. The flu shot is recommended every year for everyone 6 months and older. October is the sweet spot for winter travel, but getting it any time before departure is better than skipping it. FluMist tends to work better in young children; Fluad is the preferred formulation for adults 65 and older.

Who Should Get the RSV Vaccine Before Travel?

RSV vaccines are now recommended for adults 60 and older, pregnant travelers between 32 and 36 weeks of gestation, and indirectly for infants through maternal vaccination or monoclonal antibody prophylaxis. Unlike the flu shot, this one isn’t annual — if you received it in a prior season, you don’t need another one. Three options are available: GSK and Pfizer’s protein-based vaccines have extensive real-world safety data, while Moderna’s mRNA option is newer. If you’re in an eligible group and haven’t gotten one yet, it’s worth taking care of before a long trip — especially if you’re headed somewhere with limited healthcare access.

How Early Should I Get Travel Vaccines?

The most common mistake travelers make is waiting too long. Multi-dose series like hepatitis B take months to complete. Even single-dose vaccines like hepatitis A need two weeks to become effective. The CDC recommends seeing a travel health specialist at least four to six weeks before departure — ideally closer to six to eight weeks.

A few things to take care of before your appointment:

• Look up your destination’s entry requirements on the CDC Travelers’ Health site or your destination country’s embassy page
• Pull together your existing vaccination records if you have them
• Note any health circumstances that might affect your vaccine plan — pregnancy, current medications, or a compromised immune system

Your Passport Health specialist will handle the rest.

Which Travel Vaccines Do I Need for My Trip?

Not every traveler needs the same vaccines. Where you’re going matters, but so does what you’re doing when you get there. A business traveler staying in a city hotel in Bangkok has a different risk profile than someone doing rural volunteer work in the same country.

Length of stay plays a role too. A short trip and a months-long placement call for different planning conversations. So does your health history — prior immunizations, current medications, and any underlying conditions can all affect what’s appropriate for you.

The easiest way to sort through it is to book a pre-travel consultation. A Passport Health specialist will go through your itinerary and health history and tell you exactly what you need — no guesswork required.

Travel Vaccine Timing: How Far in Advance?

Here’s a quick reference for how far in advance each vaccine needs to be given:

Vaccine	Doses	Timing Before Departure
Yellow fever	1	10 days minimum
Hepatitis A	2 (series)	First dose: 2+ weeks; second dose: 6–12 months later
Typhoid (injectable)	1	2+ weeks
Typhoid (oral)	4 (series)	Complete 1+ week before departure
Hepatitis B	3 (series)	Full series: 6 months; accelerated options available
Tdap	1	Any time; at least 1 week preferable
MMR	1–2 doses	2+ weeks; verify immunity before booking
Polio (adult booster)	1	2+ weeks
COVID-19 booster	1	2+ weeks recommended
Influenza	1	2 weeks for full effect
RSV	1	Any time; not annual

Most vaccines can be given at the same visit — there’s no problem receiving multiple shots the same day. If your departure is coming up fast, a Passport Health clinician can help prioritize based on your itinerary and available time.

Schedule a pre-travel appointment at Passport Health →

Do I Need to Carry Proof of Vaccination When Traveling?

Some countries check vaccination documentation at the border. For yellow fever, there’s no workaround — an official International Certificate of Vaccination is required, and a phone photo won’t cut it in every country.

A few habits worth building before you leave:

• Carry a physical copy of your vaccine records alongside a digital backup
• Save digital copies somewhere accessible offline, or in multiple locations
• Use the Passport Health mobile app to pull up your records on the go
• Keep in mind that losing documentation abroad may mean getting re-vaccinated before you can return

Passport Health issues official yellow fever certificates at the time of your appointment and supports digital record access through its app.

Frequently Asked Questions

What are the must-have vaccines before international travel?

For most international travelers, the core list includes yellow fever (where required), hepatitis A, typhoid, hepatitis B, Tdap, MMR, and polio. On top of those, seasonal vaccines — COVID-19 boosters, flu, and RSV for eligible groups — are worth checking before any trip. Your specific needs depend on destination and health history.

How far in advance should I get travel vaccines?

At least four to six weeks before departure, ideally six to eight. Some multi-dose series take months to complete, and even single-dose vaccines need two weeks to take effect.

Are travel vaccines necessary if I’m healthy and fully vaccinated at home?

Yes. Routine U.S. vaccinations don’t cover everything you might encounter abroad — diseases like typhoid, hepatitis A in certain regions, and yellow fever aren’t part of the standard domestic schedule. Being healthy reduces risk; it doesn’t eliminate exposure.

Can I receive multiple travel vaccines at the same time?

Yes. Most travel vaccines can be safely given at the same visit without any increased risk.

When is proof of yellow fever vaccination required?

Entry into more than 40 countries — particularly in sub-Saharan Africa and South America — requires an official International Certificate of Vaccination. Some countries require it even if you’ve only transited through a yellow fever-endemic region.

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