When someone asks if you’re vaccinated just reply “Are you on depression medication? What brand and what dose are you taking? Bipolar meds? Are you on birth control? What type and what dose? Are you infertile or low testosterone?" I don’t think we should be pressuring people to share their personal medical history, it’s invasive and some people have embarrassing health complications where doctors say the vaccines aren’t safe for them to take and those people shouldn’t be shamed into explaining their medical conditions to everyone or worry about being ostracized for something they can’t help.
An unvaxxed friend did this on a zoom call with his coworkers when a Karen tried to make everyone answer and it shut everyone up right away and their boss immediately realized he’d be in lawsuit territory if he didn’t agree with my friend.
Do this for any social interaction, and say it with conviction and the attitude that what they’re doing is wrong and dumb and invasive and they should be ashamed of themselves. Social shaming is the only thing these people understand so turn it against them.