Is a medical certificate required for a multi-entry non-immigrant O visa application in the UK?

The current visa situation indicates that the multi-entry non-immigrant O visa is no longer available. Instead, applicants typically use the single-entry non-O visa. No medical certificate is required for the single-entry non-O visa, though applicants should be aware that the non-OA longevity visa has more stringent requirements, including a health exam and insurance. There are challenges in obtaining a medical certificate in the UK for the non-O visa, as noted by some users.