Christian Kraef1, Christian Schlein2, Jens Hiller3, Dirk Westhölter4, Ulrike Denzer3, Thomas Horvatits2, Sven Peine3, Ansgar W Lohse5, Marc Lütgehetmann6, Susanne Polywka7, Sven Pischke5. 1. I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Germany. Electronic address: c.kraef@uke.de. 2. I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Germany. 3. Institute of Transfusion Medicine, University Medical Center Hamburg-Eppendorf, Germany. 4. I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Germany; Department for Gastroenterology and Hepatology, Essen University Hospital, Germany. 5. I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Germany. 6. German Center for Infection Research (DZIF), Partner Site Hamburg-Lübeck-Borstel-Riems, Germany; Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Germany. 7. Institute of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Germany.
Abstract
BACKGROUND: Globally, an estimated 20 million Hepatitis E infections occur every year. The course of viremia and antibody response has been investigated in patients with symptomatic hepatitis E. However, the majority of HEV infections in industrialized countries take a subclinical course. OBJECTIVES: To investigate the course of HEV viremia and epitope specific anti-HEV IgM/IgG response in asymptomatic blood donors in order to understand the immune response and viral clearance in asymptomatic blood donors with HEV infections. METHODS: In this study 27 HEV viremic donors were identified by HEV-PCR during routine screening of blood donors and the course of anti-HEV IgM/IgG and HEV-RNA was retrospectively studied using RT-PCR and a commercial immunoblot (Mikrogen®) allowing classification of the antibody response according to HEV epitopes. RESULTS: At time of donation, serological testing failed to identify viremic donors as 70.4% had no detectable antibody response. Anti-HEV IgM could be detected in 22.2% of viremic donors while anti-HEV IgG could be found in 7.4%. At least three donors experienced prolonged viremia beyond 100 days. Spontaneous HEV-RNA clearance within a median time span of 57 days was observed in all 27 donors. In all donors anti-HEV IgG specific for the immunogenic viral epitope O2C could be detected in close temporal association with viral clearance. CONCLUSION: Serological testing is inappropriate for identifying HEV-viremic blood donors. Acute HEV infection in asymptomatic blood donors can persist for more than 100 days. HEV-RNA clearance coincided with the appearance of anti-HEV IgM/IgG confirming the importance of a B-cell mediated response in clearing acute infections. Anti-HEV IgM and IgG specific for the epitope O2C are associated with the clearance of HEV-viremia.
BACKGROUND: Globally, an estimated 20 million Hepatitis E infections occur every year. The course of viremia and antibody response has been investigated in patients with symptomatic hepatitis E. However, the majority of HEV infections in industrialized countries take a subclinical course. OBJECTIVES: To investigate the course of HEV viremia and epitope specific anti-HEV IgM/IgG response in asymptomatic blood donors in order to understand the immune response and viral clearance in asymptomatic blood donors with HEV infections. METHODS: In this study 27 HEV viremic donors were identified by HEV-PCR during routine screening of blood donors and the course of anti-HEV IgM/IgG and HEV-RNA was retrospectively studied using RT-PCR and a commercial immunoblot (Mikrogen®) allowing classification of the antibody response according to HEV epitopes. RESULTS: At time of donation, serological testing failed to identify viremic donors as 70.4% had no detectable antibody response. Anti-HEV IgM could be detected in 22.2% of viremic donors while anti-HEV IgG could be found in 7.4%. At least three donors experienced prolonged viremia beyond 100 days. Spontaneous HEV-RNA clearance within a median time span of 57 days was observed in all 27 donors. In all donors anti-HEV IgG specific for the immunogenic viral epitope O2C could be detected in close temporal association with viral clearance. CONCLUSION: Serological testing is inappropriate for identifying HEV-viremic blood donors. Acute HEV infection in asymptomatic blood donors can persist for more than 100 days. HEV-RNA clearance coincided with the appearance of anti-HEV IgM/IgG confirming the importance of a B-cell mediated response in clearing acute infections. Anti-HEV IgM and IgG specific for the epitope O2C are associated with the clearance of HEV-viremia.
Authors: Siddharth Sridhar; Vincent C C Cheng; Shuk-Ching Wong; Cyril C Y Yip; Shusheng Wu; Anthony W I Lo; Kit-Hang Leung; Winger W N Mak; Jianpiao Cai; Xin Li; Jasper F W Chan; Susanna K P Lau; Patrick C Y Woo; Wai-Ming Lai; Tze-Hoi Kwan; Timmy W K Au; Chung-Mau Lo; Sally C Y Wong; Kwok-Yung Yuen Journal: Emerg Infect Dis Date: 2019-03 Impact factor: 6.883