Records are meant to be broken, and rabies incubation period is no exception. Iâm often asked what the incubation period of rabies is in people. My general answer is  a long time, and we donât really know how long it can be..A report in the Annals of Neurology (Boland et al 2014) highlights this fact.ecords are meant to be broken, and rabies incubation period is no exception. Iâm often asked what the incubation period of rabies is in people. My general answer is  a long time, and we donât really know how long it can be..