Planning a holiday trip to Southeast Asia this winter, whether that means Bangkok and the Thai islands, Hanoi and Ha Long Bay, or the temples of Angkor in Cambodia? Southeast Asia travel vaccines usually start with hepatitis A, typhoid and a review of your routine immunizations, and the rest of the list depends on where you go, how long you stay and what you plan to do. Our Travel Clinic builds that list around your actual itinerary.
By Norman J. Bizon, PA-C, CTH®, Medical Director, TravelBug Health
Which Southeast Asia Travel Vaccines Do Most Travelers Need?
Thailand, Vietnam and Cambodia share most of the same core health risks, so the starting point is similar for all three. Travelers visit them in different combinations: Thailand on its own or paired with neighboring Vietnam, Cambodia's Siem Reap and Angkor Wat as a common add-on, and Mekong River cruises that run from southern Vietnam into Cambodia. Whichever pattern fits your trip, the CDC recommends the following for most travelers to the region:
- Routine immunizations. We check that you are up to date on MMR vaccine (measles, mumps, and rubella), Tdap (tetanus, diphtheria and pertussis), polio and an annual flu vaccine, which is recommended for everyone 6 months and older. The CDC advises that all international travelers be fully vaccinated against measles before they leave.
- Hepatitis A. The CDC recommends it for unvaccinated travelers 1 year and older going to all three countries.
- Typhoid. The CDC lists typhoid vaccination as recommended for most travelers to Thailand, Vietnam and Cambodia.
- Hepatitis B. The CDC recommends it for unvaccinated travelers to the region (in Thailand and Cambodia, for those younger than 60; in Vietnam, for travelers of all ages).
Japanese encephalitis and rabies are risk-based additions, covered below. If your trip is centered on Thailand alone, our guide to Thailand travel vaccines for Bangkok, Phuket and Chiang Mai goes city by city.
How Do Hepatitis A and Typhoid Spread in Southeast Asia?
Both spread through contaminated food and water, and both are found across South or Southeast Asia, Africa and parts of Latin America. The main risk factor is eating outside of major hotels and restaurants, including night markets, street stalls and family-run restaurants.
Hepatitis A (Havrix® or Vaqta®) is part of the routine US childhood immunization schedule, so we confirm your records first, since completion varies. There is no treatment for hepatitis A, only supportive care. A single dose gives effective short-term protection and still has benefit right up until the day you leave, though it works best when given at least 2 weeks before travel.
Typhoid comes in two forms. The oral vaccine (Vivotif®) is a live vaccine: four capsules over about a week, taken on an empty stomach, kept refrigerated, with the final dose at least 1 week before travel. The injectable vaccine (Typhim Vi®) is a single inactivated dose that takes up to 2 weeks to become fully effective. Travelers who pick up oral typhoid at a pharmacy without proper instructions sometimes need it repeated because it was not taken correctly.
The vaccines are one layer of protection. Our food and water rule is simple: if it comes out of a tap, it doesn't go in your mouth, including when brushing your teeth. Street food is not off limits; food cooked to order in front of you and served hot is usually safe. For the rest of the plan, see our guide to travelers' diarrhea prevention and treatment.
What About Hepatitis B?
Hepatitis B spreads through blood and body fluids, so the risk comes from medical or dental care abroad, tattoos, piercings and new sexual partners. Several formulations and schedules exist. We generally recommend Heplisav-B® (2 doses, 28 days apart) for the highest protection in the fewest doses, and the right option for you depends on your itinerary and timeline. A combined hepatitis A/B vaccine (Twinrix®) only protects once the full series is completed.
How Far in Advance Should You Get Travel Vaccines for a Holiday Trip to Southeast Asia?
We recommend scheduling your pre-travel consultation at least 6 weeks before departure (CDC recommends 6 to 8 weeks). Several vaccines that may come up for this region are multi-dose series, and the body needs time between doses to build full protection. For a mid-December departure, that means booking your consultation in October or early November.
Is It Too Late If You Leave Next Week?
No, it is still worth coming in. A single hepatitis A dose has benefit right up until departure, and injectable typhoid is a single dose. Rabies pre-exposure prophylaxis is a two-dose series on days 0 and 7, so it can still fit a short window. We prioritize what fits your timeline and cover mosquito and food and water precautions for the trip itself.
Is Malaria a Risk in Thailand, Vietnam and Cambodia?
Malaria risk in this region is real but limited to specific areas, which is why the antimalarial decision depends on your exact route. According to the CDC:
- Thailand. Antimalarial medication is recommended for provinces that border Burma (Myanmar), Cambodia (except Buri Ram Province) and Malaysia. In other areas with malaria, mosquito precautions alone are advised.
- Vietnam. Risk is in rural areas only, with rare cases in the Mekong and Red River Deltas. The CDC lists no malaria in Hanoi, Ho Chi Minh City (Saigon), Da Nang, Hai Phong, Nha Trang or Quy Nhon.
- Cambodia. Risk is primarily in pockets of rural and forested areas, with rare cases elsewhere. The CDC lists no transmission in Phnom Penh or Siem Reap.
Where medication is recommended, the options include atovaquone-proguanil (Malarone®), doxycycline and tafenoquine (Arakoda®), plus primaquine in some areas. The CDC does not list mefloquine for the Thai border provinces, Cambodia or several Vietnamese provinces. Chloroquine is not effective in this region because the malaria parasite has developed resistance to it. Primaquine and tafenoquine require a G6PD enzyme blood test first because of a hemolysis (red blood cell breakdown) risk. In the travel clinic, we assess your risk based on the provinces you will visit, how long you will stay and your medical history, so your itinerary determines whether you need a prescription at all.
Why Is Mosquito Bite Prevention So Important in Southeast Asia?
Dengue is the most common mosquito-borne illness across all three countries, and it is spread by mosquitoes that bite during the day, in cities as well as rural areas. The CDC does not recommend a dengue vaccine for travelers, so prevention depends on avoiding bites:
- Use an EPA-registered repellent with DEET or picaridin on exposed skin.
- Wear long sleeves and long pants when practical.
- Choose accommodations with air conditioning or window screens.
Chikungunya, another mosquito-borne virus that causes fever and severe joint pain, has been increasing in parts of Asia. A vaccine is available in the US: Vimkunya® is approved for ages 12 and older. ACIP recommends it for travelers going to an area with a current chikungunya outbreak, and it may be considered for extended stays of about 6 months or more in areas of elevated risk. For most short holiday trips to this region, the CDC does not generally recommend it, so we review current outbreak information at your visit.
Do You Need Japanese Encephalitis or Rabies Vaccines for Southeast Asia?
Who Should Consider the Japanese Encephalitis Vaccine?
Japanese encephalitis (brain inflammation) is a rare but serious infection spread only by mosquito bites, so vaccination is always paired with bite prevention. The vaccine (Ixiaro®) is a two-dose series. According to the CDC, it is recommended for travelers moving to the region or spending a month or more in affected areas, and may be considered for shorter trips that include rural activities such as farm stays, cycling through rice-growing areas or camping. A short holiday spent mainly in cities and beach resorts usually does not call for it. Dosing and timing are determined by your travel health consultant based on your itinerary and medical history.
Who Should Consider Pre-Exposure Rabies Vaccine?
Rabies is present in dogs across the region, and the CDC notes that dogs infected with rabies are commonly found in Cambodia. Monkeys at temple sites can also bite or scratch. Travelers planning rural travel, long stays, cycling or close contact with animals, or trips to areas where rabies treatment may be hard to reach, should consider pre-exposure rabies vaccination (Imovax® or RabAvert®). It is a two-dose preventive series on days 0 and 7, and it markedly simplifies treatment and reduces risk after a possible exposure.
Do Thailand, Vietnam or Cambodia Require a Yellow Fever Certificate?
Yellow fever does not occur in Southeast Asia, and the CDC does not recommend the vaccine for travelers flying to these countries from the US. Proof of vaccination may be required or recommended if you arrive from, or transit through, a country with yellow fever transmission risk in Africa or South America. That proof is the International Certificate of Vaccination or Prophylaxis (ICVP), also called the yellow card or yellow book. A regular doctor or PCP cannot issue it; it must come from an authorized yellow fever vaccination center and carry that center's official stamp. If your route makes it relevant, your travel health specialist needs to review your health history and itinerary first, since the decision is a risks versus benefits discussion.
Frequently Asked Questions
Do I need proof of hepatitis A or typhoid vaccination to enter these countries?
No. These vaccines protect your health during the trip and are not border requirements. The yellow fever certificate is the only vaccine document that may be requested, and only on certain routings.
Do I need different vaccines for a Mekong River cruise?
Usually the core list is the same: hepatitis A, typhoid and routine immunizations. Cruise itineraries pass through rural river areas, so we review your stops for malaria and Japanese encephalitis risk at your visit.
Can children get these vaccines?
Many of the same vaccines apply to children, but the products, doses and age limits differ. Injectable typhoid is approved from age 2 and oral typhoid from age 6, for example. Bring your child's immunization records to the consultation.
Does this guide cover Bali?
No. Bali is usually a trip of its own, and we cover it separately in our guide to vaccinations required for safe travel to Bali.
Book Your Southeast Asia Travel Vaccines in Scottsdale
Arizona travelers heading to Thailand, Vietnam or Cambodia this holiday season can get a full risk review and the vaccines their itinerary calls for in one visit. Schedule an Appointment at our Scottsdale Travel Clinic, or call (480) 435-2774, ideally at least 6 weeks before you fly.
