Fungus disease on Cephalotus is the real problem with this plant and can kill your plant in a very short space of time.
Botrytis (grey mould) hits if the light level is too low when combined with cold and humid stagnant air. Try in this case to get additional air movement and increase the light and heat levels. The fungicides currently available are useless against Botrytis, Benamyl was withdrawn a few years ago and was the only fungicide that I found worked.
Prevention is better than cure though, so be sure to remove any dead leaves or pitchers before the mould starts. If the mould appears rampant and pitcher after pitcher starts to be affected get the light level up quickly, reduce the humidity to around 40% and keep the soil on the dry side of moist combined with increased air movement.
The other fungus disease that I think is the cause of the infamous C.S.D.S. (Cephalotus Sudden Death Syndrome) is the Pythium fungus. The plant just appears to collapse, it looks as though the leaves and pitchers have dried-out having had the life sucked out of them and on examining where the leaves emerge from the compost/rhizome these appear to have black seeping up them. If you are very lucky new growth can emerge from a root section that is deeply buried, but more usually the plant is dead. Keeping the compost moist rather than wet - don't allow the plant to stand in water permanently - deters Pythium. If you've had a Pythium attack cleanliness helps in stopping a recurrence, so, clean plant pots, heat treat your composts before use, reverse osmosis water rather than rainwater and a pesticide to kill any sciarid flies (which can spread Pythium) should stop it.
I find the beneficial fungus Trichoderma works well with Cephalotus in surpressing Botrytis and Pythium. I've been using it for the past 5 years and results seem good. It enables you to maintain a higher humidity level in low light (good for larger pitchers) while suppressing the usual side effect of these conditions - a tendency for the dreaded moulds to strike. It's not foolproof though and the Trichoderma should be reapplied every 2-3 months throughout the year - I usually apply it as a drench covering the whole plant at the start of the day to allow the crown to dry out before the cooler night time temperatures.
Trichoderma is sold in the UK as Trichoderma 003 by Canna through hydroponic outlets, in New Zealand and Australia as Trichopel, in America as Plant/Rootshield from Bioworks Inc. and in Sweden and Denmark as Binab T.