Musnad Abu Ya'la al-Mawsili 149:52

Hawthara ibn Ashras Abu 'Amir narrated to us, Ja'far ibn Kaysan Abu Ma'ruf informed me, from 'Amra al-'Adawiyya, from 'Aisha, that the Messenger of Allah (may Allah bless him and grant him peace) said: "My nation will not perish except by stabbing (al-ta'n) and the plague (al-ta'un)." We said, "O Messenger of Allah, we have known stabbing, but what is the plague?" He said, "A swelling like the swelling of camels. The one who remains in it is like a martyr, and the one who flees from it is like the one who flees from the battlefield."