Chikungunya virus is spread by the bite of an infected mosquito. The most common symptoms of this acute illness are fever and joint pain. Some travelers at higher risk of exposure to chikungunya virus or at increased risk of severe disease should consider vaccination.

Cholera is caused by Vibrio cholerae bacteria and is spread by contaminated food or water. It causes severe watery diarrhea. Vaccination is recommended for certain travelers at risk of exposure in areas of active cholera transmission.

Coronavirus disease 2019 (COVID-19) is caused by the SARS-CoV-2 virus, which typically spreads from person to person through respiratory droplets and small particles. It occurs worldwide. Vaccination is routinely recommended in the United States. Travelers should be up to date on COVID-19 vaccination.

Dengue viruses are spread through the bite of an infected mosquito. Dengue is an acute febrile illness that can have serious complications. Dengue occurs in many tropical and subtropical regions. A vaccine is licensed, but vaccination is not recommended by CDC for travelers.

Diphtheria is a bacterial infection of the skin or respiratory tract spread through respiratory droplets or contact with infected wounds. The disease exists in regions where diphtheria-containing vaccines are not used or where few people get vaccinated. Vaccination is routinely recommended in the United States. Travelers who are not up to date can become infected.

Hepatitis A virus causes acute liver disease. Hepatitis A virus is typically spread through the fecal-oral route, including through contaminated food or water. It is common in many parts of the world. Vaccination of U.S. children is routinely recommended. Unvaccinated travelers should be vaccinated before travel to areas where hepatitis A is common.

Hepatitis B virus can cause acute and chronic liver disease, including cancer. The virus is found in the blood and body fluids of infected people. Hepatitis B is found worldwide. CDC recommends vaccination of all people through age 59 years. Unvaccinated travelers should be vaccinated before travel to areas where hepatitis B is common.

Influenza is an acute respiratory viral disease that causes seasonal epidemics during winter months. It occurs worldwide. Annual seasonal vaccination is routinely recommended. Travelers who have not had a current seasonal vaccine should get one before travel.

JE virus is spread by the bite of an infected mosquito in some parts of Asia and the Western Pacific. Infection may lead to severe disease and death. The risk to most travelers is very low, but vaccine may be recommended for certain travelers based on their destination, itinerary, and duration of travel.

Measles virus is highly contagious, spread when an infected person coughs, sneezes, or talks. It causes an acute febrile rash illness that can be severe. Vaccination is routinely recommended in the United States. Most U.S. measles cases occur among unvaccinated travelers who get infected while traveling internationally and their contacts who are not fully vaccinated.

Meningococcal disease is a serious bacterial illness spread through close contact with an infected person. It occurs worldwide, but vaccination is recommended for travelers to some parts of the world, such as the “meningitis belt” of Sub-Saharan Africa, as well as travelers to the Hajj or Umrah in Saudi Arabia.

Mpox is caused by the mpox virus and is spread by direct skin-to-skin contact. It was primarily found in central and west Africa, but a global outbreak began in 2022, and it now circulates in many places where it was not previously present. CDC recommends vaccination of people based on behavioral risk factors, not specific destinations.

Mumps virus infection is spread by contact with infectious saliva or respiratory droplets. It often causes salivary gland swelling and is common in many parts of the world. Vaccination is routinely recommended in the United States. Unvaccinated travelers are at risk.

Pertussis, also known as whooping cough, is a highly contagious bacterial respiratory disease that can cause fits of uncontrollable coughing. It is present worldwide. Vaccination is routinely recommended in the United States. Travelers should be up to date.

Pneumococcal disease is a bacterial infection that occurs worldwide. Vaccination of children, people with certain health conditions, and older adults is routinely recommended in the United States. Travelers should be up to date.

Polio is a viral infection that affects the nervous system and is spread by fecal-oral transmission. Vaccination is routinely recommended in the United States. All travelers who are not up to date with polio vaccines are at risk. Adult travelers to a polio-affected country who have been previously vaccinated may need a one-time booster.

Rabies is a deadly viral neurologic disease. Although any mammal can transmit rabies, dog bites are how most travelers get rabies. Vaccination is recommended for certain travelers based on their destination, activities, and duration of travel.

Rubella is a viral rash illness that can cause birth defects in infants whose mothers are infected during pregnancy. It has been eliminated through vaccination in South and North America. Vaccination is routinely recommended in the United States. Unvaccinated travelers going to areas with rubella can get infected.

TBE is a serious viral disease transmitted primarily by the bite of infected ticks in parts of Asia and Europe. Vaccination is recommended for certain travelers whose destination and activities put them at risk.

Tetanus is a disease that causes severe muscle spasms (“l(fā)ockjaw”) caused by bacteria typically found in soil. It is present worldwide and any unvaccinated person can get it. Vaccination is routinely recommended in the United States. Travelers should be up to date on tetanus vaccination.

Typhoid fever is caused by a bacteria spread where water and food may be unsafe and sanitation is poor. Vaccination is recommended for certain travelers based on their destination and itinerary.

Yellow fever virus is spread by the bite of an infected mosquito and causes a serious acute illness. It is found in certain parts of South America and Africa. Travelers to areas where yellow fever occurs may be recommended or required to be vaccinated.