Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
About Traveler's Health
Traveling can increase your chances of getting sick. A long flight can increase your risk for deep vein thrombosis. Once you arrive, it takes time to adjust to the water, food, and air in another place. Water in developing countries can contain viruses, bacteria, and parasites that cause stomach upset and diarrhea. Be safe by using only bottled or purified water for drinking, making ice cubes, and brushing your teeth. If you use tap water, boil it or use iodine tablets. Food poisoning can also be a risk. Eat only food that is fully cooked and served hot. Avoid unwashed or unpeeled raw fruits and vegetables.
If you are traveling out of the country, you might also need vaccinations or medicines to prevent specific illnesses. Which ones you need will depend on what part of the world you're visiting, the time of year, your age, overall health status, and previous vaccinations. See your doctor 4 to 6 weeks before your trip. Most vaccines take time to become effective.
Centers for Disease Control and Prevention
It sits within Infections and Wellness and Lifestyle.
When to speak to someone. Reading about a topic cannot tell you whether it applies to you. Speak to a doctor or pharmacist if symptoms are severe, sudden, getting worse, or simply not going away — and seek emergency care immediately for chest pain, breathing difficulty, sudden weakness or confusion, or a serious allergic reaction.
Where to read more
Rather than paraphrase, we point you to the primary sources. Every link below is to a government health agency, a national institute or a recognised medical body — grouped by what you are trying to find out.
Start Here
- Staying Healthy While You TravelNemours Foundation
- Travelers' HealthCenters for Disease Control and Prevention
Related Issues
- Air Quality and Ionizing Radiation during TravelCenters for Disease Control and Prevention
- Heat and Cold Illness in TravelersCenters for Disease Control and Prevention
- Injury and Death during TravelCenters for Disease Control and Prevention
- International AdoptionCenters for Disease Control and Prevention
- Post-Travel Dermatologic ConditionsCenters for Disease Control and Prevention
- Post-Travel DiarrheaCenters for Disease Control and Prevention
- Sex and TravelCenters for Disease Control and Prevention
- Travelers' Health: Cruise Ship TravelCenters for Disease Control and Prevention
- Travelers' Health: Immunocompromised TravelersCenters for Disease Control and Prevention
- Travelers' Health: Mosquitoes, Ticks, and Other ArthropodsCenters for Disease Control and Prevention
- Travelers' Health: Travel Health KitsCenters for Disease Control and Prevention
- Travelers' Health: Zoonotic Exposures -- Bites, Stings, Scratches, and Other HazardsCenters for Disease Control and Prevention
- Your Health AbroadDepartment of State, Bureau of Consular Affairs
Clinical Trials
- ClinicalTrials.gov: Jet Lag SyndromeNational Institutes of Health
Medical subject headings
Clinicians and researchers index this subject under Air Travel, Travel. These are the terms to use when searching medical literature.
This page is built from the MedlinePlus health topic record for Traveler's Health, a service of the U.S. National Library of Medicine (NLM), National Institutes of Health. Information is from MedlinePlus.gov. PocketsInfo is not affiliated with, and is not endorsed by, the NLM or the NIH. Retrieved 30 July 2026.