1. A health messenger is a person who is ordered to deliver health information. An envoy refers to a person who is ordered to send an envoy, generally referring to a person who is ordered to do things. See Book of Rites: The commander-in-chief, the president and Guan Xiucai all belong to the Party. Musicians, messengers and boys belong to the main party.
2. A health worker is a respectful name for a doctor. It is also the lofty duty of doctors.