Vaccinations and Travel Health for Cambodia: What Americans Need

Cambodia malaria risk — and whether you actually need pills

This is the question that worries Americans most, and the honest answer is reassuring: for the trip the vast majority of US visitors actually take, malaria risk is low. The CDC reports essentially no malaria risk in Phnom Penh, in Siem Reap town, and at the temples of Angkor Wat. If your trip is the classic first-timer loop — temples, capital, maybe the coast around Sihanoukville or Kep — you are spending almost all of it in low-risk or no-risk zones.

Where the risk rises is the remote stuff: forested areas, the border regions (particularly near the Thai and Laos frontiers), and rural provinces away from the main towns, especially overnight in the rainy season. If your itinerary includes jungle trekking, the northeastern provinces of Ratanakiri or Mondulkiri, remote homestays, or extended rural travel, malaria moves from a non-issue to a real conversation with your travel doctor about antimalarial pills.

There is a Cambodia-specific wrinkle worth knowing: the country is a known hotspot for drug-resistant malaria, which is exactly why you do not self-prescribe and do not rely on pills you brought from a previous trip somewhere else. A US travel clinic will recommend the right drug for your specific route if pills are warranted — and will tell you plainly when they are not. Either way, mosquito-bite prevention does more day-to-day work than any pill: it also guards against dengue, which has no vaccine routinely given to travelers and is present across Cambodia year-round.

• Use an EPA-registered repellent with DEET (20-30%) or picaridin on exposed skin, reapplied as directed.
• Wear long sleeves and long pants at dawn and dusk, when the malaria mosquito is most active.
• Sleep under a mosquito net or in screened, air-conditioned rooms in rural areas.
• Treat clothing and gear with permethrin if you are heading into forested or remote zones.
• Remember dengue mosquitoes bite during the day — bite prevention is an all-day habit, not just an evening one.

Because the pills-or-no-pills decision turns entirely on where you are going, it is worth settling early rather than at the airport pharmacy. Map your route against the low-risk tourist circuit — Phnom Penh, Siem Reap, Angkor Wat, the coast — versus the high-risk remote zones, and you will know which conversation to have before your clinic visit instead of guessing on the day.

Yellow fever, entry rules, and what Immigration actually checks

Here is where required and recommended come back into focus. Cambodia has exactly one vaccine entry rule, and it almost never applies to Americans: a yellow fever vaccination certificate is required only if you are arriving from, or have recently transited through, a country with risk of yellow fever transmission. Those are mostly in sub-Saharan Africa and tropical South America. If you fly to Cambodia directly from the United States, or connect through a hub like Seoul, Tokyo, Bangkok, or Singapore, this rule does not touch you.

The practical takeaway: if your trip is US to Cambodia and back, with normal Asian or Middle Eastern connections, you need no proof of vaccination of any kind to enter. The only travelers who hit the yellow fever requirement are those routing through Africa or South America on the same trip — for example, a multi-country itinerary that includes Kenya or Brazil before Cambodia. If that is you, carry your yellow card; if it is not, this paragraph is the last you need to think about it.

What Cambodian Immigration actually checks at the airport is your passport and your visa, not your health. Your eVisa is the document that matters at the desk, and it is purely about identity and your approved entry — there is no medical question on the application and no shot record requested at any point. The 2025 e-Arrival Card added a separate pre-arrival declaration, but it captures travel and contact details, not your vaccination history. Health prep is for your own protection; the entry process is paperwork.

It is worth confirming the current entry picture before any international trip, since rules can shift. For US travelers, the authoritative reads are the State Department country information page and the US Embassy in Phnom Penh, and the broader practical picture — what to pack, what to expect, what surprises first-timers — lives in our things to know before visiting Cambodia guide for Americans.

Practical health prep: food, water, kit, and insurance

Vaccines and pills are the headline, but day-to-day health in Cambodia comes down to a few simple habits. The most common thing that derails an American trip is not an exotic disease — it is travelers diarrhea from food and water. Drink bottled or properly treated water, skip ice unless you know it is made from filtered water, eat at busy stalls where food turns over fast and is cooked hot in front of you, and be a little cautious with raw salads and unpeeled fruit early in the trip while your system adjusts.

Pack a compact travel health kit. The core is simple: any prescription medication you take regularly (in its original labeled packaging, with enough for the whole trip plus a buffer), an oral rehydration solution, loperamide for stomach upset, a broad-spectrum antibiotic if your doctor prescribes one for travelers diarrhea, basic pain relief, sunscreen, your mosquito repellent, and a small first-aid set. Cambodia has pharmacies, but stock and quality vary, and you do not want to be hunting for your specific medication in a small town.

Travel insurance is the one I push hardest on, precisely because my desk sees what happens without it. Cambodia has good private clinics in Phnom Penh and Siem Reap, but serious cases are often evacuated to Bangkok or Singapore, and a medical evacuation can run into tens of thousands of dollars out of pocket. A travel policy with solid medical coverage and emergency evacuation is not a luxury for Cambodia — it is the single best dollar-for-dollar protection you can buy, and it costs a fraction of one night in a foreign hospital.

One more practical detail trips up Americans more than vaccines do: bringing your own prescription medication into Cambodia the right way. Some common US medications are controlled or restricted in Cambodia, and the rules on quantities and documentation are not obvious. Carry everything in its original labeled packaging, bring a copy of your prescription or a letter from your doctor, pack only a reasonable trip-length supply, and declare anything you are unsure about so a routine medication does not become a border problem.

A simple pre-trip timeline (and how the visa fits)

Put it all on a calendar and it stops feeling overwhelming. Four to six weeks before you fly, book a travel-clinic appointment — this is the window some vaccines need to take full effect, and it leaves room for a multi-dose course if your clinician recommends one. At that visit, settle the recommended vaccines against your real itinerary, the malaria question based on your route, and any prescriptions you want to carry. In the final two weeks, top up your travel health kit and confirm your travel insurance with medical evacuation coverage.

1. 1
   Book a travel clinic (4-6 weeks out)

   See a clinician early enough for vaccines to take effect and for any multi-dose course they recommend.

2. 2
   Match vaccines and malaria to your route

   Settle Hepatitis A, typhoid, and the situational vaccines against your real itinerary, and decide on antimalarial pills by route.

3. 3
   Pack your health kit and insurance (final 2 weeks)

   Top up the travel health kit and confirm travel insurance with solid medical and emergency evacuation coverage.

4. 4
   Apply for your Cambodia eVisa

   Once dates are firm, the Tourist eVisa is $80 all-in, approved in 3 business days, with no medical documents at any step.

5. 5
   File the e-Arrival Card (within 7 days)

   Submit the separate e-Arrival Card in the 7-day window before arrival; it captures travel and contact details, never a shot record.

The visa runs on a completely separate, much shorter clock, and it needs none of the health prep above. A Tourist eVisa is $80 USD all-in, approved in 3 business days, valid for 3 months from issue, and gives you a 30-day single-entry stay. A Business eVisa is $90 USD on the same timeline. There is no medical document at any step. Worth flagging for trip planning: the tourist auto-extension ended in November 2025, so your 30-day stay is now a firm ceiling — build your dates inside it.

So the whole picture is two tidy tracks. Health: clinic at four to six weeks, kit and insurance in the final fortnight. Paperwork: apply for your Cambodia eVisa once your dates are firm — most US travelers do it two to three weeks out — and then file the separate e-Arrival Card within the 7-day window before you fly. Sort both in the right order and you land in Phnom Penh with nothing left to worry about except which temple to see first.