The causes of high lymphatic percentage in newborns are due to two main diseases. First, it is caused by a viral infection. If the child is infected with a virus, the lymphocytes in the child’s blood are relatively high. For example, if the child is caused by an acute upper respiratory tract infection, in this case, the child will be infected with rhinovirus or influenza virus, parainfluenza virus, etc. The child’s blood will then have a basically normal level of white blood cells and a relatively high percentage of lymph. Secondly, it is caused by acute leukemia such as gonorrhea. If a child has acute leukemia, it is most often caused by acute lymphoid leukemia. In this case, the child’s lymphocyte percentage is significantly high. In this case, parents should have the child undergo a bone marrow aspiration to further confirm the diagnosis.