Malaria Tablets vs Vaccines — What's the Difference?

People ask this a lot. "I need malaria vaccines before Kenya" — or some version of that. And it's a reasonable assumption that if there's a disease risk, there's a vaccine. That's how most of travel health works. But malaria is different, and it trips people up.

Here's the short version: for most travellers, there is no malaria vaccine. There are tablets.

Why no vaccine?

Malaria is caused by a parasite — Plasmodium — not a virus or bacterium. Vaccines work brilliantly against viruses and reasonably well against some bacteria. Parasites are considerably more complicated. They're bigger, more genetically complex organisms that change and adapt in ways that make it hard for a vaccine to reliably target them.

There is a malaria vaccine — RTS,S, sold as Mosquirix — but it's designed for young children in sub-Saharan Africa as part of routine childhood immunisation programmes. The efficacy isn't high enough for it to be recommended for travellers, and it requires a complex dosing schedule that doesn't work well for short-term travel. It's a significant public health achievement, but it's not the answer for someone going on safari for two weeks.

So what do the tablets actually do?

Antimalarial tablets don't prevent infection — they prevent the parasite from replicating and causing disease if you do get infected. The distinction matters. You can still get bitten by an infected mosquito on prophylaxis. The tablets suppress the parasite's lifecycle before it can make you seriously ill.

There are three main options prescribed to travellers: atovaquone-proguanil (Malarone is the brand name most people know), doxycycline, and mefloquine. Each works differently, has different side effect profiles, and suits different destinations and trip lengths. Your travel clinic will recommend the right one based on where you're going — some malaria strains in certain regions are resistant to certain drugs — and your personal circumstances.

The part people get wrong

Taking the tablets. Specifically — stopping them early.

This is genuinely common. You come home, you feel fine, the tablets have a slightly annoying side effect (doxycycline makes some people sun-sensitive, mefloquine can cause vivid dreams), and you think — I'm home now, I'm fine, I'll stop. Wrong. Depending on the drug, you need to continue for one to four weeks after leaving a malaria area. The parasite can survive in your system after the bite, and the tablets need to clear it before you stop.

People get malaria after returning home because they stopped their tablets early. It happens every year.

Tablets plus repellent — not tablets instead of repellent

Antimalarials are one layer of protection, not a complete solution. Malaria mosquitoes bite predominantly between dusk and dawn. DEET-based repellent on exposed skin during those hours, long sleeves and trousers where practical, and sleeping under a treated net in high-risk areas — these are not optional extras if you're in a serious malaria zone. They work alongside the tablets, not instead of them.

Kenya, Tanzania, Uganda, much of West Africa, parts of South and Southeast Asia — these aren't places where you take one tablet a day and consider yourself sorted. The risk is real and the layered approach is warranted.

Do you always need prophylaxis?

No. Risk varies significantly by destination and itinerary. Nairobi and the highlands of Kenya have minimal malaria risk. Coastal areas and game parks are different. Bangkok and most of Southeast Asia's cities are low-risk. The Amazon basin is not.

This is another reason why a travel clinic conversation matters — not because you need to take tablets for every trip to a warm country, but because the answer genuinely depends on where specifically you're going and what you're doing there.

Check malaria risk and vaccine requirements for your destination on WhichVax →