Although Brazil has free health service available to everyone, it is recommended to get a health insurance beforehand and use private healthcare services which are very good (in contrast to public hospitals, that are often overcrowded), but may be very expensive. Most doctors and hospitals expect immediate payment in cash.
Medical emergency number is 192.
Many prescription medications are available in Brazil over the counter but be sure to know the generic name of your medication - it may be sold in Brazil under a different name.
Tap water quality varies place to place, so it is generally recommended not to drink it without boiling or sterilizing first; bottled water is preferred. Use only pasteurized milk or boil it before drinking. Also, vegetables should be cooked, fruits peeled and meat and fish well cooked.
Avoid food from street and beach vendors, particularly at the end of the day, when the food quality gets worse due to high temperatures.
It is recommended to get vaccinations for hepatitis and yellow fever before traveling to Amazon region. Yellow fever vaccination and anti-malaria drugs are recommended before traveling to central - western Brazil. Dengue fever is common during the summer so take mosquito repellent and make sure that the place you stay at is cleared of any stagnant water.
For their safety, travelers should exercise caution at all times, particularly in the main cities.
Violent street crimes, including crimes against tourists, are present, mostly in large cities, especially in the north, northeast and southeast of Brazil.
By law, everyone must carry a photo ID at all times. Visitors should always carry a photocopy of the passport (leaving the original in hotel's safe). Theft is a problem at airports and bus stations. Try not to display any valuable things you are caring (cameras, laptops, expensive watches or jewelery etc; hide them in bags or backpacks or even plastic bag from local store so no one would guess what's inside). Dress down in casual clothes that blend in.
Avoid walking at night or in high-risk areas - take a taxi instead.
Try to only use ATMs that are inside banks and always hide the number pad when you're typing you PIN. There has been increasing number of thefts by hacking into bank accounts after using an ATM machine.