Sahih Bukhari Volume 9, Book 87, Hadith Number 162.

Narrated By ‘Abdullah bin ‘Umar : Concerning the dream of the Prophet in Medina: The Prophet said, “I saw (in a dream) a black woman with unkempt hair going out of Medina and settling at Mahai’a. I interpreted that as (a symbol of) the epidemic of Medina being transferred to Mahai’a, namely, Al-Juhfa.”