Before you travel internationally, ensure you are up to date on all routine immunizations as well as travel vaccines. Vaccines are available to prevent 25 life-threatening diseases, and 24 of them are administered in the United States. Vaccinations may hurt a little, but the diseases they prevent are a lot worse, some even life-threatening. Immunization shots are essential, protecting against diseases like measles, mumps, rubella, hepatitis B, polio, tetanus, diphtheria and pertussis (whooping cough). Some people think only infants and children need vaccines, but it is important for adults to receive them as well.

Your immune system helps your body fight germs by producing substances to combat them. Once it does, the immune system “remembers” the germ and fights it again. A vaccine contains germs that have been killed or weakened. When given to a healthy person, it triggers the immune system to respond and build immunity. Before vaccines, people became immune only by actually getting the disease and surviving it. Immunizations provide an easier and less risky way to become immune.

More and more Americans are traveling internationally each year. Today more than a third of Americans have a passport. It is important to remember some international travel, especially to developing countries and rural areas, carries higher health risks. These risks depend on a number of factors including where you are traveling, your activities while traveling, your current health status and your vaccination history.

Vaccines can help protect you against a number of serious diseases found in some developing countries, such as typhoid and yellow fever. Vaccine-preventable diseases that are rare in the United States, such as polio, still exist in other parts of the world. Measles still occurs year-round in many countries, including common destinations in Europe and Asia. Worldwide, about 20 million people get measles each year; about 146,000 die. Many of the measles cases reported in the United States in 2014 were linked to a large outbreak in the Philippines.

This year so far, about 170 people were reported to have measles in the United States; most of these people were not vaccinated or didn’t know if they were vaccinated. Nearly all the cases were associated with international travel. The Centers for Disease Control and Prevention recommend all U.S. travelers six months of age or older be protected from measles and receive the MMR (measles, mumps and rubella) vaccine prior to leaving for trips abroad unless they can show they were previously vaccinated or had measles in the past.

Talk with your health care professional when planning international travel, especially if you have any health conditions. Since not all primary health care providers stock all travel vaccines, you may need to visit a travel clinic to receive the vaccines you need. Make an appointment with your provider or a travel clinic at least four to six weeks prior to international travel. This allows time to complete any vaccine series and build up immunity.

The CDC website can tell you which vaccinations you need depending on your destination and what kind of traveler you are. The International Association for Medical Assistance to Travellers website also gives information about required and recommended vaccinations, health risks, food and water conditions and travel and mental health conditions for the country you are traveling to.

When talking to your health care professional about travel, also make sure you are up to date on your routine vaccines, such as the MMR vaccine. Check if the country you are traveling to requires proof of yellow fever vaccine. This vaccine can only be given by a registered provider and must be given at least 10 days prior to travel. You’ll need to get a stamped vaccine certificate.

Some countries require foreign visitors to carry an International Certificate of Vaccination (aka Yellow Card) or other proof they have had certain inoculations or medical tests before entering or transiting the country. Before you travel, check the country-specific information and contact the embassy of the country for current entry requirements.

The World Health Organization held World Immunization Week April 24–30, 2016, highlighting recent gains in immunization coverage and outlining further steps countries can take to “Close the Immunization Gap” and meet global vaccination targets by 2020. Immunization prevents 2–3 million deaths annually. An additional 1.5 million deaths could be avoided if global vaccination coverage improves. Today an estimated 18.7 million infants, nearly one in five children worldwide, are still missing routine immunizations for preventable diseases such as diphtheria, pertussis and tetanus.

Take the CDC quiz to check on vaccinations you need. Visit www2.cdc.gov/nip/adultimmsched

The content of this article is for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition.