Someone else’s diarrhea makes (shouldn't make) your ass itch.
Proverb's meaning
Keep to yourself; keep your nose out of other people’s business.
Equivalent proverb
Cry more than the bereaved.
From: Mandinka of West Africa
General comments
The Mandinka (or Malinike, Mandingo, Mande) live in the Gambia, Senegal, Guinea, Guinea-Bissau, Mali and Côte d'Ivoire. In Nigeria, they say "take Panadol (a type of pain killer) for someone else's headache".