This study aimed to provide baseline knowledge of coral diseases prevalence and coral health at nine
reef sites in the northern Egyptian Red Sea: I (El-Ain Al-Sukhna), II (Ras Za’farana), III (Hurghada), IV (Ras
Ghozlani), V (Old Quay), VI (Yolanda reef), VII (Ras Umm Sid, Sharm El-Sheikh), VIII (WoodHouse reef,
Sharm El-Sheikh), and IX (canyon reef, Dahab). Sites IV, V and VI are located in Ras Mohamed, marine
protected area. Field surveys of coral diseases and signs of compromised health in the studied reefs revealed a
mean prevalence of 1.03%. Macroscopic observations were diagnosed as: black band disease (0.44%), white
syndrome (0.13%), pink line syndrome (0.04%), ulcerative white spots (0.02%), skeletal eroding band (0.001%),
coral bleaching (2.2%), Drupella cornus snail predation (0.1%), fish predation (0.2%), pigmentation response
(0.13%), sediment damage (0.08%), algae overgrowth (0.06%) and sponge overgrowth (0.04%). Prevalence of
coral diseases and bleaching were higher in non-MPA sites than in MPA sites. The highest prevalence of coral
diseases was recorded on the coral Favia stelligera, followed by Porites lutea, and Goniastrea edwardsi.
Enhanced local anthropogenic stresses and increasing sea surface temperature due to global warming are the
suggested potential factors responsible for the initiation and the persistence of some coral diseases in the studied
reefs.