Here's the thing: the people complaining don't believe it's a minor effect.
Consider this: people are playing, here, an MMORPG. Some of the people who are playing it are going to care enough about those RPG elements to be pretty upset when their character is infected with this plague and all that goes along with it.
Let them dislike it.
From what I've seen, they are letting you like it (the OP excluded). They just want the opportunity to be heard as to why they do not enjoy it. On the other side of things, any time anyone says he dislikes the plague, he's attacked with names of every sort.
You would say it's a minor impact on these players, but they may feel its a major impact, and the fact is, we're talking about a game here - something for and based on entertainment. By it's very definition, what people enjoy or do not enjoy about it will be tremendously subjective. If someone feels its a major impact, its a major impact, because the nature of games is that their impact is very personal.
Excellent post. And the very reasons some should not have to do a event they donot wish to. I can watch a horror movie and sleep good at night. Some cannot...does that mean they are being silly and I can make fun of them for feeling that way? It really is a matter of respecting others.