[1] Fundacao Prosangue, Hemoctr Sao Paulo, Sao Paulo, Brazil
[2] Univ Sao Paulo, Fac Med, Dept Infect Dis, Sao Paulo, Brazil
[3] Univ Sao Joao del Rei, Divinopolis, Brazil
[4] Sao Paulo Inst Trop Med, Lab Gastroenterol & Hepatol, Sao Paulo, Brazil
[5] Univ Sao Paulo, Sch Med, Dept Gastroenterol, Sao Paulo, Brazil