Clinical, virologic and immunologic features of a mild case of SARS-CoV-2 reinfection

Pauline Vetter; Samuel Cordey; Manuel Schibler; Laure Vieux; Lena Despres; Florian Laubscher; Diego O Andrey; Romain Martischang; Stephan Harbarth; Clémence Cuvelier; Meriem Bekliz; Isabella Eckerle; Claire-Anne Siegrist; Arnaud M Didierlaurent; Christiane S Eberhardt; Benjamin Meyer; Laurent Kaiser; Geneva Center for Emerging Viral Diseases

doi:10.1016/j.cmi.2021.02.010

Clinical, virologic and immunologic features of a mild case of SARS-CoV-2 reinfection

Clin Microbiol Infect. 2021 Feb 20;27(5):791.e1-791.e4. doi: 10.1016/j.cmi.2021.02.010. Online ahead of print.

Authors

Pauline Vetter¹, Samuel Cordey², Manuel Schibler³, Laure Vieux⁴, Lena Despres⁴, Florian Laubscher³, Diego O Andrey³, Romain Martischang⁵, Stephan Harbarth⁵, Clémence Cuvelier⁶, Meriem Bekliz⁷, Isabella Eckerle⁷, Claire-Anne Siegrist⁸, Arnaud M Didierlaurent⁸, Christiane S Eberhardt⁹, Benjamin Meyer¹⁰, Laurent Kaiser³; Geneva Center for Emerging Viral Diseases

Affiliations

¹ Geneva Centre for Emerging Viral Diseases, Geneva, Switzerland; Laboratory of Virology, Division of Laboratory Medicine, Geneva, Switzerland. Electronic address: pauline.vetter@hcuge.ch.
² Laboratory of Virology, Division of Laboratory Medicine, Geneva, Switzerland.
³ Geneva Centre for Emerging Viral Diseases, Geneva, Switzerland; Laboratory of Virology, Division of Laboratory Medicine, Geneva, Switzerland.
⁴ Division of Occupational Medicine, Geneva, Switzerland.
⁵ Infection Control Division, WHO Collaborating Center for Patient Safety, Geneva University Hospitals & Faculty of Medicine, Geneva, Switzerland.
⁶ Division of Intensive Care, Geneva University Hospitals, Geneva, Switzerland.
⁷ Geneva Centre for Emerging Viral Diseases, Geneva, Switzerland; Department of Microbiology and Molecular Medicine, Geneva, Switzerland.
⁸ Geneva Centre for Emerging Viral Diseases, Geneva, Switzerland; Centre for Vaccinology, Department of Pathology and Immunology, Geneva, Switzerland.
⁹ Centre for Vaccinology, Department of Pathology and Immunology, Geneva, Switzerland; Division of General Pediatrics, Department of Woman, Child and Adolescent Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland; Emory Vaccine Center, Emory University, Atlanta, Georgia, USA.
¹⁰ Centre for Vaccinology, Department of Pathology and Immunology, Geneva, Switzerland.

Abstract

Objectives: To report a case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection 6 months after the first infection in a young healthy female physician. Both episodes led to mild coronavirus disease 2019 (COVID-19).

Methods: SARS-CoV-2 infections were detected by real-time reverse transcriptase PCR (RT-PCR) on nasopharyngeal specimens. Reinfection was confirmed by whole-genome sequencing. Kinetics of total anti-S receptor binding domain immunoglobulins (Ig anti-S RBD), anti-nucleoprotein (anti-N) and neutralizing antibodies were determined in serial serum samples retrieved during both infection episodes. Memory B-cell responses were assessed at day 12 after reinfection.

Results: Whole-genome sequencing identified two different SARS-CoV-2 genomes both belonging to clade 20A, with only one nonsynonymous mutation in the spike protein and clustered with viruses circulating in Geneva (Switzerland) at the time of each of the corresponding episodes. Seroconversion was documented with low levels of total Ig anti-S RBD and anti-N antibodies at 1 month after the first infection, whereas neutralizing antibodies quickly declined after the first episode and then were boosted by the reinfection, with high titres detectable 4 days after symptom onset. A strong memory B-cell response was detected at day 12 after onset of symptoms during reinfection, indicating that the first episode elicited cellular memory responses.

Conclusions: Rapid decline of neutralizing antibodies may put medical personnel at risk of reinfection, as shown in this case. However, reinfection leads to a significant boosting of previous immune responses. Larger cohorts of reinfected subjects with detailed descriptions of their immune responses are needed to define correlates of protection and their duration after infection.

Keywords: COVID-19; Immunity; Reinfection; SARS-CoV-2; Sequencing.