As named typhus, it is a viral illness, infectious of the cat, who drags problems of diarrhea: the kittens are then very weaken and dehydrated. They die then quickly because the treatments are very uncertain and often without success. Nowadays, of part the systematic vaccination, there is not case of feline leucopénie anymore at the Koratses but it can occur very well among kittens no or vaccinated badly. The delay of action in rédhibition is of thirty days if a certificate of suspicion is emitted by a veterinarian (in the five days after the receipt of the animal).