With measles making a global comeback - cases increased 79 percent in 2023 - the CDC is issuing new guidelines for those planning to travel abroad.“Many international destinations are reporting increased numbers of cases of measles,” says the Centers for Disease Control and Prevention (CDC) website, adding: “The majority of measles cases imported into the United States occur in unvaccinated U.S. residents who become infected during international travel.”In particular, the CDC website says Americans who intend to visit other countries should consult with a doctor six weeks prior if there’s any question about whether they’ve had the measles vaccine. Travelers are at risk of contracting measles if they've not been fully vaccinated two weeks ahead of traveling abroad, says the agency's travel advisory.“All international travelers should be fully vaccinated against measles with the measles-mumps-rubella (MMR) vaccine, including an early dose for infants 6–11 months, according to CDC’s measles vaccination recommendations for international travel.In another notable update, Russia and Malaysia have been added to the CDC’s map of 46 countries that are experiencing a significant uptick in measles cases. Some of the additional countries where health officials have reported large measles outbreaks include Afghanistan, Armenia, India, Indonesia, Nepal, Qatar, Saudia Arabia, Turkey, and the United Arab Emirates. To view the full list of countries experiencing a significant measles outbreak, visit the CDC website.And if you do travel abroad and develop any of the following symptoms, the CDC recommends seeking medical care: