Our society in general is too afraid of germs. Bacteria and dirt are, generally speaking, good for you. And in fact, washing too often, especially using soap too often, is actually bad for you. It can wash away your skins natural oils and protective layers of bacteria.
As everyone has said, just find a good, professional gym with good cleaning policies.
My gym is dirty as fuck (it's primarily a Muay Thai gym and the owner is an ex-fighter who just doesn't really give a fuck) and I've still only had one, very minor, skin infection.
I have a shower before hand, no soap, just to make sure I don't stink when I get to class. I shower as soon as I get home, just with normal soap and I wash my gear ASAP too, to prevent it from getting too stinky.
Honestly, things like your phone, your shoes, public hand rails etc will likely be far more dirty than a BJJ gym.
Stop worrying about germs and live a little. The benefits of BJJ far outweigh the harm of a few germs.