aksumite empire

In Islamic history, the Year of the Elephant is when Usurper general Abraha, ruler of Askumite Controlled South-Western Arabia, Is stopped in his tracks by a miraculous plague, as he attempts to conquer Medina, and possibly all of the Hejaz. What happens if he succeeds and Islam is never born, I...

Not sure if it was already the case in OTL, yet what if the Plague of Justinian managed to affect most if not all of Arabia as well as the Horn of Africa? Aside from negatively impacting OTL population growth of the Arabs, what other knock-on effects on would this ATL Plague of Justinian likely...