Blood tests for HFMD cannot detect the precise virus associated with the hand, but can only detect viral or bacterial infections. If fever, rash and other suspected cases of HFMD occur, routine blood tests can assist in detecting whether or not it is a viral infection, and then combined with the baby’s clinical manifestations to give antipyretic, antiviral and other symptomatic treatment. Hand, foot and mouth disease is most common in infants and young children under the age of 4, and is more common in set children. The disease is highly contagious and can cause certain epidemics. Most of the rashes appear on the day of onset or the 2nd day, accompanied by fever, the whole course of the disease is about 7-10 days, the prognosis is good.