Jabir (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) visited Umm Sa'ib (or Umm Musaiyyab) and asked her, "What ails you O Umm Sa'ib (or Umm Musaiyyab)? You are shivering." She replied: "It is a fever, may Allah not bless it!" He said to her, "Do not revile fever, for it cleanses out the sins of the sons of Adam in the same way that a furnace removes the dirt of iron."[Muslim].
App reference: Book 18, Hadith 216
Arabic/English book reference: Book 18, Hadith 1726