Some people think they have B.O or Bad Breath because they make people cough or sneeze. These allergy-type of reactions are not caused by odors, they are caused by an irritant that is odorless.
Same thing with other allergens like pollen, cats, peanuts, etc - nothing to do with smells.
So if you make people cough, google 'people are allergic to me' or 'PATM', there's a thread on medhelp with 100s of people who suffer from the same thing. No one has B.O there, we have what we call 'PATM'. We have yet to find the reason why we emit this irritant.