Flu and family party

Ugh so annoyed. Went to family party last night and a couple ppl there had severe flu, were throwing up. I was assured before going just one person had a cold. Nope! Lots of finger foods being breathed on by the sickies. Hoping hoping I don’t get anything. Not vaccinated but not sure that would matter as this year’s shot is supposedly not effective anyway. Am told not to take any high doses of vitamin C. Anything you All suggest I do at this point to prevent?