Thailand’s distinctive health profile is not “high malaria everywhere”. Malaria risk is low in rural, forested border areas with Cambodia, Laos and Myanmar, and very low or absent on many common tourist routes, including Bangkok, Chiang Mai, Koh Samui, Koh Phangan and Pattaya. Malaria tablets are not automatically needed for every Thailand trip, but bite avoidance still matters. Dengue, Zika and chikungunya are spread by mosquitoes that often bite in the daytime, including in towns and cities. There is no routine tablet that prevents these infections. Repellent, covered skin, screened rooms and care around standing water are practical measures, not optional extras. Zika is especially important if you are pregnant or planning pregnancy. Hepatitis A is commonly recommended for previously unvaccinated travellers because it spreads through contaminated food and water. Tetanus should be up to date, and typhoid may be considered if food hygiene is likely to be less reliable, especially on longer or more independent trips. Hepatitis B may be relevant for longer stays, new sexual partners, medical or dental treatment, contact sports, tattoos or work involving blood exposure. Rabies is present in Thailand. Dogs, cats, monkeys and bats can all create problems after a bite or scratch. Japanese encephalitis is mainly a concern for longer rural stays, repeated travel, or time around rice fields and pig farming areas, particularly during the May to October transmission season in northern regions.