[1] VET AFFAIRS MED CTR, INFLAMMATORY BOWEL DIS LAB, HOUSTON, TX 77030 USA
[2] BAYLOR COLL MED, CHILDRENS NUTR RES CTR, USDA ARS, HOUSTON, TX 77030 USA
[3] BAYLOR COLL MED, CHILDRENS NUTR RES CTR, DEPT MED, DIV MOLEC VIROL, HOUSTON, TX 77030 USA
[4] BAYLOR COLL MED, CHILDRENS NUTR RES CTR, DEPT PEDIAT, HOUSTON, TX 77030 USA
[5] AB PRISMA, LIMA, PERU
[6] JOHNS HOPKINS UNIV, BALTIMORE, MD 21205 USA
[7] UNIV UPPSALA HOSP, DEPT CLIN MICROBIOL, UPPSALA, SWEDEN