So because the powers that be have granted us with a 10th season of X Files come next January, I've been rewatching the original nine on Netflix (an activity I cannot recommend highly enough). There's a disappointing lack of sneezing of any kind (they spend so much time outside and in the rain and neither Mulder nor Scully catches cold even once???? Madness I tell you, sheer madness).
BUT.
In s8e17 (Empedocles), Gillian Anderson herself seems under the weather (she sounds all congested and sniffly, poor baby, and in the first scene she has with Mulder she carries a tissue with her everywhere, be still my beating heart.) They don't incorporate it into the episode at all, which is a shame, but, y'know, I'll take what I can get.
Also, there's always fanfic, amIright?