Synesthesia isn't a disease you contract. It's the instance in which people associate certain letters, numbers, or words with a specific color or place. For example: a synesthetic person may always...
It is a rare condition in which stimuli are perceived by different senses. Some people might see music or taste colors.
If you want to go further into the topic, there are projectile and associative...
Not especially for a synesthete (I don't think!), unless they wanted to become a scientist researching the condition which most people would be able to do.