I might be wrong. But I think that the only 2 things Qatar goverment look into are HIV and TB. I also think my grandpa have a hepa B&C and he was able to get a resident permit in Qatar. My understaning which might be wrong is hepa b&c is not contagious. I think your husband should be fine getting a resident permit ASLONG he is NOT working in some kinda grocery store or something where he might be able to touch the food that is being handed to customers or have direct contact with people in hospitals,clinics...etc
I hope that you guys make it to Qatar here with no problems:)