حَدَّثَنِي أَبُو الطَّاهِرِ، وَحَرْمَلَةُ بْنُ يَحْيَى، - وَاللَّفْظُ لأَبِي الطَّاهِرِ - قَالاَ أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ، قَالَ ابْنُ شِهَابٍ فَحَدَّثَنِي أَبُو سَلَمَةَ بْنُ عَبْدِ الرَّحْمَنِ، عَنْ أَبِي، هُرَيْرَةَ حِينَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ لاَ عَدْوَى وَلاَ صَفَرَ وَلاَ هَامَةَ ‏"‏ ‏.‏ فَقَالَ أَعْرَابِيٌّ يَا رَسُولَ اللَّهِ فَمَا بَالُ الإِبِلِ تَكُونُ فِي الرَّمْلِ كَأَنَّهَا الظِّبَاءُ فَيَجِيءُ الْبَعِيرُ الأَجْرَبُ فَيَدْخُلُ فِيهَا فَيُجْرِبُهَا كُلَّهَا قَالَ ‏"‏ فَمَنْ أَعْدَى الأَوَّلَ ‏"‏ ‏.‏
Translation
Jabir b. 'Abdullah reported Allah's Apostle (ﷺ) as saying

There is no transitive disease, no safar, no ghoul. He (the narrator) said: I heard Abu Zubair say: Jabir explained for them the word safar. Abu Zubair said: safar means belly. It was said to Jabir: Why is it so? He said that it was held that safar implied the worms of the belly, but he gave no explanation of ghoul. Abu Zubair said: Ghoul is that which kills the travellers.