See this interesting article:
Why do you rarely see deceased termites in the Termitat? Termites deal with deaths of colony members in a way to protect the colony as a whole. Zootermopsis angusticolis, the species in the Termitat, has evolved methods to minimize the threat of infection of the colony from older decaying bodies by quickly making a meal for healthy members of those that have just died from natural causes or battle. If access to the body has not been available and it has started to decay and might harbor pathogens, it is buried in an out of the way area.
Wood does not contain significant levels of protein so these occasional meals of deceased members allow recycling of a precious nutrient. This behavior is all part of the elegant design of this species after millions of years of evolution.