[1] Univ South Carolina, South Carolina Honors Coll, Columbia, SC 29208 USA
[2] Univ South Carolina, Arnold Sch Publ Hlth, Dept Epidemiol & Biostat, 915 Greene St,Rm 456,Discovery 1 Bldg, Columbia, SC 29208 USA
[3] Univ South Carolina, Coll Nursing, Columbia, SC 29208 USA
[4] Drexel Univ, Dept Hlth Management & Policy, Philadelphia, PA 19104 USA
[5] Univ South Carolina, Sch Med, Dept Pathol Microbiol & Immunol, Columbia, SC 29208 USA