well maybe not the excact bacteria or fungus, but when being ill our liver takes over and produces more glucose, in earlier days maybe we wouldn´t get much to eat when being ill, so our body has learned to take over at illness .... nowadays we have an overload of foods allways available ... but the bodynature usually takes many generations to change its inherited patterns..
it could be interesting to know what triggers this extra liver boost, if it is the raised body temperature or it is the raised number of White blood cells in action or whatever it could be