[1] UMass Amherst, Dept Anthropol, Amherst, MA USA
[2] Univ Oxford, Nuffield Dept Med, Oxford, England
[3] Univ Durham, Dept Anthropol, Durham, England
[4] Univ Coll Cork, Dept Obstet & Gynecol, Cork, Ireland
[5] Parkview Med Coll, Microbiol, Sylhet, Bangladesh
[6] UMass Amherst, Dept Anthropol, Machmer Hall,240 Hicks Way, Amherst, MA 01003 USA