Muwatta Imam Malik Book of The Evil Eye, Hadith 18

Yahya related to me from Malik that he had heard from Bukayr ibn Abdullah ibn al-Ashajj from Ibn Atiya that the Messenger of Allah ﷺ said, "There is no contagion, no hama and no serpent in a hungry belly. However, the possessor of sick livestock must not stop at the same place as the possessor of healthy livestock, but the possessor of healthy livestock may stop wherever he wishes."
They said, "Messenger of Allah, Why is that?" The Messenger of Allah ﷺ said, "It is harmful."

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ بْنِ الأَشَجِّ، عَنِ ابْنِ عَطِيَّةَ، أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ " لاَ عَدْوَى وَلاَ هَامَ وَلاَ صَفَرَ وَلاَ يَحُلَّ الْمُمْرِضُ عَلَى الْمُصِحِّ وَلْيَحْلُلِ الْمُصِحُّ حَيْثُ شَاءَ " . فَقَالُوا يَا رَسُولَ اللَّهِ وَمَا ذَاكَ فَقَالَ رَسُولُ اللَّهِ ﷺ " إِنَّهُ أَذًى " .