some diseases spread some dont how to know which will

Knowing how infectious diseases spread will help protect you from getting sick while traveling and decrease the likelihood that you will spread illness to other travelers. The following information will empower you to be a more responsible traveler — so that you can protect your health and the health of others. Two main types of illnesses that you may be able to spread easily to another person are respiratory illnesses (those that affect your breathing) and foodborne illnesses (those spread by eating, drinking, or putting something in your mouth that has been contaminated).

If you decide to travel while you have a respiratory illness, don’t spread your germs to others

Cover your mouth and nose when you cough or sneeze.
Throw away used tissues. (Place them in a trash can or the sick bag when on a flight.)

Wash your hands often with soap and water. Wash after you use the bathroom, sneeze or cough, and before eating or touching anything that you might put in your mouth. (Hand sanitizer with alcohol may be used if no running water is available.)
Do not share food or drink with others.