The Wyandotte, Ottawa, Peoria, and Modoc Tribes of Oklahoma and their members shall be entitled to participate in the programs and services provided by the United States to Indians because of their status as Indians, including, but not limited to, those under section
13 of this title, and for purposes of sections
2005 to
2005f of title
42. The members of such tribes shall be deemed to be Indians for which hospital and medical care was being provided by or at the expense of the Public Health Service on August 16, 1957.