[1] Heinrich Heine Univ, DGHID, Dusseldorf, Germany
[2] Arsi Univ, DGHID, Res & training Ctr, Hirsch Inst Trop Med, Asella, Ethiopia
[3] Charite Univ Med Berlin, Dept Infect Dis & Pulm Med, Augustenburger Pl 1, D-13353 Berlin, Germany
[4] Arsi Univ, Asella, Ethiopia
[5] Charite Univ Med Berlin, Inst Trop Med & Int Hlth, Berlin, Germany
[6] Robert Koch Inst, Dept Infect Dis Epidemiol, Berlin, Germany