After a child’s viral infection, the specific symptoms are mainly combined with the cause of the disease into the judgment, common causes include upper respiratory infection, hepatitis, EBV infection and B brain, etc., the symptoms mainly include cold symptoms, digestive symptoms, lymph node enlargement and neurological symptoms. 1. Upper respiratory tract infection: mainly manifested as nasal congestion, runny nose, cough, chest pain and a series of other symptoms, some patients will also be accompanied by headache, fever and so on. 2. Hepatitis: Hepatitis virus infection is mainly characterized by abnormal digestive system, jaundice and pain in the liver area. 3. EBV infection: the most common is the appearance of multiple lymph node enlargement, and some of them will also be accompanied by skin rashes and hepatosplenomegaly and other symptoms. 4. Encephalitis B: After the occurrence of encephalitis B virus infection, it may cause abnormalities in brain tissue, which may further lead to neurological symptoms, such as drowsiness, headache, epilepsy, etc. The symptoms of encephalitis B virus infection should be treated promptly. After discovering viral infection, one should be admitted to the hospital for medical observation and standardized treatment after confirming the specific condition to avoid delaying the condition.