22 C.F.R. § 41.108 – Medical examination.

(a) Requirements for medical examination. An applicant for a nonimmigrant visa shall be required to take a medical examination if:
1. (1) The alien is an applicant for a K nonimmigrant visa as a fiance(e) of a U.S. citizen or as the child of such an applicant; or,
2. (2) The alien is seeking admission for medical treatment and the consular officer considers a medical examination advisable; or,
3. (3) The consular officer has reason to believe that a medical examination might disclose that the alien is medically ineligible to receive a visa.
(b) Examination by panel physician. The required examination, which must be carried out in accordance with United States Public Health Service regulations, shall be conducted by a physician selected by the alien from a panel of physicians approved by the consular officer or, if the alien is in the United States, by a medical officer of the United States Public Health Service or by a contract physician from a list of physicians approved by the DHS for the examination of INA 245 adjustment of status applicants.
(c) Panel physician facility requirements. A consular officer may not include the name of a physician on the panel of physicians referred to in paragraph (b) of this section unless the physician has facilities to perform required serological and X-ray tests or is in a position to refer applicants to a qualified laboratory for such tests.