It has a certain influence to apply for a health certificate when you have a cold. To apply for a health certificate is generally to go to a designated hospital for a physical examination, and to check five items: biochemistry, hepatitis B and blood routine. If the patient catches a cold, there will be a hint in the routine blood examination, and the number of lymphocytes will increase obviously, or the number of white blood cells and neutrophils will increase, which will affect the health certificate.