Felix Buder1, Markus Bauswein1, Clara L Magnus1, Franz Audebert2, Henriette Lang2, Christof Kundel3, Karin Distler3, Edith Reuschel4, Matthias Lubnow5, Thomas Müller5, Dirk Lunz6, Bernhard Graf6, Stephan Schmid7, Martina Müller7, Hendrik Poeck8, Frank Hanses9,10, Bernd Salzberger10, David Peterhoff1, Jürgen J Wenzel11, Barbara Schmidt1,11, Benedikt M J Lampl12. 1. Institute of Medical Microbiology and Hygiene, University of Regensburg, Regensburg, Germany. 2. Praxiszentrum Alte Mälzerei, Regensburg, Germany. 3. Medizinische Klinik 1, Hospital Barmherzige Brüder, Regensburg, Germany. 4. University Department of Obstetrics and Gynecology at the Hospital St Hedwig of the Order of St John, University of Regensburg, Regensburg, Germany. 5. Department of Internal Medicine II, University Hospital Regensburg, Regensburg, Germany. 6. Department of Anesthesiology, University Hospital Regensburg, Regensburg, Germany. 7. Department of Internal Medicine I, University Hospital Regensburg, Regensburg, Germany. 8. Department of Internal Medicine III, Hematology and Oncology, University Hospital Regensburg, Regensburg, Germany. 9. Emergency Department, University Hospital Regensburg, Regensburg, Germany. 10. Department of Infection Prevention and Infectious Diseases, University Hospital Regensburg, Regensburg, Germany. 11. Institute of Clinical Microbiology and Hygiene, University Hospital Regensburg, Regensburg, Germany. 12. Public Health Department Regensburg, Germany.
Abstract
BACKGROUND: From a public health perspective, effective containment strategies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be balanced with individual liberties. METHODS: We collected 79 respiratory samples from 59 patients monitored in an outpatient center or in the intensive care unit of the University Hospital Regensburg. We analyzed viral load by quantitative real-time polymerase chain reaction, viral antigen by point-of-care assay, time since onset of symptoms, and the presence of SARS-CoV-2 immunoglobulin G (IgG) antibodies in the context of virus isolation from respiratory specimens. RESULTS: The odds ratio for virus isolation increased 1.9-fold for each log10 level of SARS-CoV-2 RNA and 7.4-fold with detection of viral antigen, while it decreased 6.3-fold beyond 10 days of symptoms and 20.0-fold with the presence of SARS-CoV-2 antibodies. The latter was confirmed for B.1.1.7 strains. The positive predictive value for virus isolation was 60.0% for viral loads >107 RNA copies/mL and 50.0% for the presence of viral antigen. Symptom onset before 10 days and seroconversion predicted lack of infectivity with negative predictive values of 93.8% and 96.0%. CONCLUSIONS: Our data support quarantining patients with high viral load and detection of viral antigen and lifting restrictive measures with increasing time to symptom onset and seroconversion. Delay of antibody formation may prolong infectivity.
BACKGROUND: From a public health perspective, effective containment strategies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be balanced with individual liberties. METHODS: We collected 79 respiratory samples from 59 patients monitored in an outpatient center or in the intensive care unit of the University Hospital Regensburg. We analyzed viral load by quantitative real-time polymerase chain reaction, viral antigen by point-of-care assay, time since onset of symptoms, and the presence of SARS-CoV-2 immunoglobulin G (IgG) antibodies in the context of virus isolation from respiratory specimens. RESULTS: The odds ratio for virus isolation increased 1.9-fold for each log10 level of SARS-CoV-2 RNA and 7.4-fold with detection of viral antigen, while it decreased 6.3-fold beyond 10 days of symptoms and 20.0-fold with the presence of SARS-CoV-2 antibodies. The latter was confirmed for B.1.1.7 strains. The positive predictive value for virus isolation was 60.0% for viral loads >107 RNA copies/mL and 50.0% for the presence of viral antigen. Symptom onset before 10 days and seroconversion predicted lack of infectivity with negative predictive values of 93.8% and 96.0%. CONCLUSIONS: Our data support quarantining patients with high viral load and detection of viral antigen and lifting restrictive measures with increasing time to symptom onset and seroconversion. Delay of antibody formation may prolong infectivity.
Authors: Gabriel Acca Barreira; Emilly Henrique Dos Santos; Maria Fernanda Bádue Pereira; Karen Alessandra Rodrigues; Mussya Cisotto Rocha; Kelly Aparecida Kanunfre; Heloisa Helena de Sousa Marques; Thelma Suely Okay; Adriana Pasmanik Eisencraft; Alfio Rossi Junior; Alice Lima Fante; Aline Pivetta Cora; Amelia Gorete A de Costa Reis; Ana Paula Scoleze Ferrer; Anarella Penha Meirelles de Andrade; Andreia Watanabe; Angelina Maria Freire Gonçalves; Aurora Rosaria Pagliara Waetge; Camila Altenfelder Silva; Carina Ceneviva; Carolina Dos Santos Lazari; Deipara Monteiro Abellan; Ester Cerdeira Sabino; Fabíola Roberta Marim Bianchini; Flávio Ferraz de Paes Alcantara; Gabriel Frizzo Ramos; Gabriela Nunes Leal; Isadora Souza Rodriguez; João Renato Rebello Pinho; Jorge David Avaizoglou Carneiro; Jose Albino Paz; Juliana Carvalho Ferreira; Juliana Ferreira Ferranti; Juliana de Oliveira Achili Ferreira; Juliana Valéria de Souza Framil; Katia Regina da Silva; Karina Lucio de Medeiros Bastos; Karine Vusberg Galleti; Lilian Maria Cristofani; Lisa Suzuki; Lucia Maria Arruda Campos; Maria Beatriz de Moliterno Perondi; Maria de Fatima Rodrigues Diniz; Maria Fernanda Mota Fonseca; Mariana Nutti de Almeida Cordon; Mariana Pissolato; Marina Silva Peres; Marlene Pereira Garanito; Marta Imamura; Mayra de Barros Dorna; Michele Luglio; Nadia Emi Aikawa; Natalia Viu Degaspare; Neusa Keico Sakita; Nicole Lee Udsen; Paula Gobi Scudeller; Paula Vieira de Vincenzi Gaiolla; Rafael da Silva Giannasi Severini; Regina Maria Rodrigues; Ricardo Katsuya Toma; Ricardo Iunis Citrangulo de Paula; Patricia Palmeira; Silvana Forsait; Sylvia Costa Lima Farhat; Tânia Miyuki Shimoda Sakano; Vera Hermina Kalika Koch; Vilson Cobello Junior Journal: Rev Inst Med Trop Sao Paulo Date: 2022-07-13 Impact factor: 2.169