AITA for wanting my family to take my concerns about illness seriously?

I (M23) don’t like getting sick. I especially don’t like anything stomach illness-related. I had food poisoning once that landed me in the hospital and to this day, I am an emetophobe (scared of throwing up). And it’s winter and I always get sick during the winter so I try to avoid that.

There’s a bunch of stuff going around (in the USA at least) but my main concern is norovirus. Long story short: you get this, you’ll be having stuff coming out of both ends for days. It’s like food poisoning, but a bit worse.

My two oldest siblings (brother and sister, basically 40), don’t really care about protecting themselves. They will be around sick people, sometimes not practice good hygiene, and it’s unbelievable to me. They’ll sneeze into their hand, not wash their hands, and just be around you (when not necessary) when they should go take care of themselves. The thing that annoys me the most is that they invalidate my concerns about health and they just shut me up because “I’m dramatic” or “it’s not that serious.” Im the “health freak” of the family yet when they get sick, they come to me about what they should do.

My sister has a kid who is sick and throwing up. However, my brother visited my sister and then came back to my place and told me they visited her and that my niece is sick. I immediately thought of norovirus and I got a bit mad because whyyy would you hang out together and risk yourself getting sick? Because if it is that, you gotta disinfect and all that stuff. My brother tells me that “it’s not that serious” and that I need to “stop freaking out.” I wouldn’t freak out if I knew my brother practiced proper hygiene but he doesn’t. To make things worse, he calls my sister about my “freak out”— and now my sister annoyed at ME for being annoyed at BROTHER for being at her house (bc sick people) and being near me… and just also bothering her in general about sicknesses and her kid being sick. Im not the one who called her or wanted to. I voiced my concern to him only and he decided to include her for some reason.

I’m not asking for much, just to take precautions around me because they don’t and then I always up sick. Happens frequently. It’s disgusting. This side of me has existed before COVID and I wish people took my concerns seriously. AITA?