It is narrated from Sayyiduna Sa'd bin Malik, Sayyiduna Khuzaymah bin Thabit and Sayyiduna Usamah bin Zayd (may Allah be pleased with them) that the Prophet (peace and blessings be upon him) said: "This plague is a punishment, and the remnant of the punishment that came down upon nations. When it breaks out in a land and you are present there, do not leave it fleeing; and when it breaks out in a land where you were not, then do not enter it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الجنائز / 6559