Thank you for your query Would you please clarify a few things for me? 1)how old is your husband? 2)has he had any recent respiratory tract infections? Like sinusitis or bronchitis? 3)has he had any head injuries? Or injuries to the nose? Or a stuffy nose (no infection /allergies)? 4) does he smoke? Or have any dental problems (caries, a new filling)? 5)is he on any medication? Any change in smell, if it lasts more than a few days, should be investigated. A recent infection can cause retention of mucous which can cause a foul smell but can also be sensed by others if close enough to the person. Head injuries, other changes in the olfactory pathway like a polyp or nerve damage can cause changes in smell which is sensed only by the person affected. I recommend a consult with an ENT (Ear, nose, throat) specialist to rule out the above possible causes. Early diagnosis and treatment will prevent further progression. Hope this helps. Please feel free to contact us if you have any questions. Wish you both good health