For Bali, malaria tablets are not routinely advised for most travellers. The risk is classed as low, so bite avoidance and awareness are usually the key measures. That changes if your itinerary reaches higher-risk parts of Indonesia, especially Papua, where antimalarial tablets are normally recommended. Tell the clinician if Bali is only one stop. Mosquitoes still deserve proper attention. Dengue is a risk in Indonesia and is spread by mosquitoes that often bite in the daytime, including in towns and built-up areas. Zika is also reported, so pregnancy or plans to conceive should be discussed before travel. Chikungunya is another mosquito-borne infection to be aware of, particularly for longer or repeated trips. Hepatitis A is commonly recommended for previously unvaccinated travellers because it spreads through contaminated food and water. Typhoid vaccination is also often considered, especially for longer stays, lower-cost accommodation, rural travel, or situations where food hygiene may be less predictable. Tetanus should be up to date. Rabies is present in Indonesia and has been reported in domestic animals. Bali’s dogs and tourist-site monkeys are the practical issue here. A bite, scratch or lick on broken skin needs urgent medical advice, even if you had pre-travel rabies vaccination. Japanese encephalitis may be relevant for longer rural stays, repeated travel, or time near rice fields and pigs.