When a baby has a routine blood test, high lymphocytes and low neutrophils depend on the absolute value. If the absolute value of neutrophils is low, the percentage of neutrophils will be lower and the percentage of lymphocytes will be higher, while the lower absolute value of neutrophils is the focus. This is usually seen in viral infectious diseases, respiratory viral infections such as adenovirus and rhinovirus infections; intestinal viral infections such as rotavirus, norovirus and coxsackievirus infections; chronic viral infections such as cytomegalovirus infections and EBV infections can occur as described above. Severe bacterial infections can also cause a decrease in neutrophil values, and certain drug ingredients themselves can cause a decrease in neutrophils.