Back in 541-542 an outbreak killed about 40% of the city’s population. But even during the period 1347-1453, a total of 61 plague reports were noted.
They only had the wealth, peace and population to focus on science to a very small degree. That they managed to stay afloat for as long as they did is a testament to the science the original Romans left them, and which we can thank the Byzantine's for preserving.
