Staying Healthy in Machu Picchu
The main health considerations are to take care to eat in good quality establishments with good hygiene standards and to be aware of the altitude. Machu Picchu is considerably lower in altitude than Cusco though, and lower than the Sacred Valley too, so problems are very rare indeed. If ascending Huayna Picchu takes care of the steep paths.
The Center for Disease Control has some useful advice for travelers. https://wwwnc.cdc.gov/travel/destinations/list/
The UK’s NHS also provides some guidance for visitors to Machu Picchu. https://www.fitfortravel.nhs.uk/destinations