Julie...One way of finding out the number of cases is to patrol the corridors on each deck and see how many tables are placed against cabin doors (for the food drop.) I saw a couple on last Coral cruise I was on with you and others, 13 Sept to 22 Sept. Young Mic (MicCanberra) also said he saw a few.
Yep, mask up people, protect yourself and others.
Sailnsurf, to answer your question, personal decision as to whether you go. But if it assists you I am a Coeliac with a very low immune system, I often catch whatever is going around. Touch wood on my recent Coral Princess cruise, 13 Sept to 22 Sept, I caught nothing, I hope.