I'm attending an event next week at place where there have been 3 meningitis cases. Is it a good idea to get the vaccine? Or prevent in other ways?

Meningitis. It is not likely that one week would provide sufficient time for your body to build up sufficient antibodies to protect you. There are medications that can be used to provide protection against meningitis. I suggest you consult with your doctor to see if you would benefit from taking an antibiotic to protect you.