For purposes of retirement or separation for physical disability under chapter
61 of title
10, a commissioned officer of the Service shall be credited, in addition to the service described in section 1208(a)(2) of that title, with active service with the Public Health Service, other than as a commissioned officer, which the Surgeon General determines is comparable to service performed by commissioned officers of the Service, except that, if there are more than five years of such service, only the last five years thereof may be so credited. For such purposes, such section
1208
(a)(2) shall be applicable to officers of the Regular or Reserve Corps of the Service.