Some countries require that you have certain vaccinations prior to entry. Other countries may not have mandatory immunizations, but it may be a good idea to have them anyway. At a minimum, be sure your Tetanus shot is up to date. Hepatitis A & B vaccines may also be something to ask your health care provider about.
OSU Health Services offers immunizations and information regarding health conditions abroad.
The Center for Disease Control and Prevention also has some excellent destination specific information.
In Oklahoma City, Passport Health also serves as a traveler’s resource.