This is a really good question! Your husband will be very susceptible to bacteria and fungal infections so this machine and all the tubing will have to be scrupulously clean. I’m just thinking out loud, your husband is already immunocompromised with his health and the meds he’s on and so far this hasn’t been a problem for him health wise.
So whatever he’s doing to keep it clean seems to be working ok. Swabbing with 90% ETOH will certainly disinfect the surfaces it touches and is a good idea.

But I also know he can’t possibly be the only BMT patient who’s potentially had this issue come up. So my suggestion is that when you’re both in for a meeting with the transplant team, ask for their opinion. Or you can send a message through your husband’s portal to a nurse coordinator of his health team. They’re really great with fielding questions and concerns.

How is your husband maintaining his machine now to avoid bacterial growth?