Sometimes the public transport is so dirty, and you see all kinds of people, some in very dirty clothes using it. There are sometimes little kids without diapers?. At times there is foul odor as well. What if I happen to be sitting on one of these seats, and the bad stuff unknowingly has clung on to me?
Answer
If you are confident that impurities have soiled your clothes, then only you should change them. If it is merely a suspicion, without any substance, you should ignore it.
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai