It is narrated from Salim bin Abdullah bin Amir bin Rabi'ah (may Allah have mercy on him) that Abd al-Rahman bin Awf (may Allah be pleased with him) informed Umar (may Allah be pleased with him) - when he was on the road to Syria and the news reached him that plague had broken out there - of this saying of the Prophet (peace and blessings be upon him): "This sickness - or this illness - is a punishment with which those before you were punished. So when it is in a land where you are not present, do not go there; and when it is in a land where you are present, do not leave it fleeing from it." The narrator said: So Umar (may Allah be pleased with him) returned with the people that same year.
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 265