Peru’s distinctive health issue is altitude. Cusco sits at around 3,399 metres, Puno is higher, and parts of the Inca Trail climb above 4,000 metres. Acute mountain sickness can affect fit people as well as unfit people. Headache, nausea, poor sleep and breathlessness after ascent should be taken seriously, especially if symptoms worsen rather than settle. Hepatitis A is commonly recommended for previously unvaccinated travellers because it spreads through contaminated food and water. Tetanus should be up to date, particularly if you will trek, cycle or spend time away from good medical facilities. Typhoid vaccination is often discussed for Peru, especially for longer trips, rural stays or situations where food hygiene may be uncertain. Yellow fever is the vaccine that needs itinerary detail. It is generally relevant for several lower-altitude eastern and Amazon regions, including areas such as Loreto, Madre de Dios, Ucayali and parts of Cusco region below 2,300 metres. It is not usually advised for itineraries limited to Lima, Cusco city, Machu Picchu or the Inca Trail. Some people cannot safely have this vaccine, so it needs proper screening. Malaria risk is low and focused mainly in the Amazon basin, especially Loreto and other rural areas below 2,000 metres. Many travellers need bite avoidance rather than tablets, though antimalarials may be considered for higher-risk people or more remote itineraries. Dengue, Zika and Oropouche are also mosquito-borne concerns, so daytime bite prevention matters. Rabies is present, with pre-travel vaccination worth discussing for children, runners, cyclists, long stays and remote travel.