If you lose your health certificate, you can reissue it. You need to take all your personal documents and photos to the health care department of the hospital, do a good job of blood routine, urine routine and related tests under the guidance of the doctor, let the doctor get the health certificate, and then apply for a new one at the window where you apply for the health certificate. You need to register and get a new health certificate, which usually takes 5 working days. You need to take good care of your health certificate number and don't lose it again.
The health certificate is valid for one year. It will be invalid after more than one year. After the health certificate is invalid, you can go to the hospital for re-examination and apply for a health certificate.