[1] Inst Infect & Immun, Dept Pathol, London, England
[2] Univ London, Dept Surg, London SW17 0RE, England
[3] Johannes Gutenberg Univ Mainz, Dept Pharmaceut Biol, D-55128 Mainz, Germany
[4] Surrey & Sussex Healthcare NHS Trust, East Surrey Hosp, Dept Gastroenterol, Redhill RH1 5RH, Sussex, England
[5] Dafra Pharma Nv, B-2300 Turnhout, Belgium
[6] Univ Klinikum Tubingen, Inst Trop Med, D-72074 Tubingen, Germany