San Diego is home to many retirees and others who love to travel. The U.S. Dept. of State has useful information about traveling abroad. At their website you can access information about passports, registering your travel abroad, taking medicines on your trip, customs and import information, and immunizations required for various areas.
You can also check the website for what travel warning and alerts are in effect for a specific country. A Travel Warning is a warning against travel to certain countries where a condition may make the country dangerous or unstable. Currently, some of the countries listed with Travel Warnings are Pakistan, Iran, Iraq, Afghanistan, Yemen, Colombia, Nepal, and Somalia.
Travel Alerts are issued for usually short term conditions such as a natural disaster, a coup, or acts of terrorism. Countries under a Travel Alert at this time are Mexico, China, Comoros, and the Arabian Peninsula.