5-year-old baby herpes fever usually lasts 1 to 2 days, individual baby fever may be longer. 5 year old baby herpes generally refers to chickenpox – herpes zoster virus caused by chickenpox, the virus will be transmitted through the mucous membranes of the upper respiratory tract, the child’s initial infection with this virus will have about 14 days of incubation period, after the incubation period will appear symptoms of fever, usually fever for 1 to 2 days, then the rash will appear. A small number of babies with low immunity or underlying diseases may have slower progression of the disease or may be co-infected with skin infections, encephalitis, pneumonia, etc., in which case the baby’s fever may last longer or even recur. Each baby’s physical condition is different, herpes fever time may also have differences, it is recommended to go to the hospital in time to reduce the adverse effects of the disease.