Related Rule
United States of America
Practice Relating to Rule 88. Non-Discrimination
Section C. Wounded and sick
The US Field Manual (1956) provides that sick and wounded captives shall be provided with the same medical care as friendly sick and wounded. It also restates Article 12 of the 1949 Geneva Convention II. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, §§ 92 and 215.
The US Air Force Pamphlet (1976) states:
One of the important principles relating to wounded and sick requires medical care and humane treatment to friend and foe without distinction founded on sex, race, nationality, religion, political opinions or similar criteria. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, § 3-4(d); see also §§ 12–2(a) and 13-2.
The US Naval Handbook (1995) provides: “Wounded and sick personnel falling into enemy hands must be … cared for without adverse distinction.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-2.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Transportation, US Coast Guard, October 1995 (formerly NWP 9 (Rev. A)/FMFM 1-10, October 1989), § 11-4.
The US Naval Handbook (2007) states: “Wounded and sick personnel falling into enemy hands must be … cared for without adverse distinction along with the enemy’s own casualties.” 
United States, The Commander’s Handbook on the Law of Naval Operations, NWP 1-14M/MCWP 5-12.1/COMDTPUB P5800.7, issued by the Department of the Navy, Office of the Chief of Naval Operations and Headquarters, US Marine Corps, and Department of Homeland Security, US Coast Guard, July 2007, § 11.6.