[1] Univ Cologne, Fac Med, Cologne, Germany
[2] Univ Hosp Cologne, Polyclin Operat Dent & Periodontol, Cologne, Germany
[3] Univ Cologne, Univ Hosp Cologne, Childrens & Adolescents Hosp, Fac Med,Pediat Nephrol, Cologne, Germany
[4] Fac Med, Dept Orthodont, Cologne, Germany
[5] Univ Hosp Cologne, Cologne, Germany
[6] Wisplinghoff Labs, Cologne, Germany
[7] Witten Herdecke Univ, Inst Virol & Microbiol, Witten, Germany
[8] Univ Cologne, Inst Med Microbiol Immunol & Hyg, Cologne, Germany