Yes. Being sick can definitely affect recall - as well as how vivid your dreams are. Everything from the type of illness, to how comfortable you are when you sleep; to the effects of the medicine you're taking can affect your dreaming experience.

Usually, mine will end up getting more vivid when I have something like the flu. I tend to sleep longer and that, alone, makes me have more vivid dreams. Also, if I have to keep waking up during the night, that helps me to remember more, too. It all depends.