From the link: Be careful for those who want to tour Tulum- According to the CDC, as of 1 May 2015, a total of 27 cases of hepatitis A have been reported in USA travelers who went to Tulum, Mexico. All of the people traveled between the dates of 15 Feb 2015, and 20 Mar 2015. CDC advises travelers to the area to get vaccinated against hepatitis A and follow all food and water precautions. In addition, federal health authorities tell returning travelers from Tulum, Mexico during the last 14 days to talk to your doctor about receiving a dose of hepatitis A vaccine, which can prevent or reduce the symptoms of hepatitis A if given within 14 days of exposure. Hepatitis A is a liver disease that results from infection with the hepatitis A virus. It can range in severity from a mild illness lasting a few weeks to a severe illness lasting several months. Hepatitis A is usually spread when a person ingests fecal matter -- even in microscopic amounts -- from contact with objects, food, or drinks contaminated by the feces or stool of an infected person. The best way to prevent hepatitis A is by getting vaccinated. CDC warns travelers to Tulum, Mexico of hepatitis A risk | Outbreak News Today