Reinfection by the SARS-CoV-2 Gamma variant in blood donors in Manaus, Brazil

BMC Infectious Diseases

Marcio K. Oikawa¹  Ester Cerdeira Sabino²  Lewis F. Buss²  Nuno R. Faria³  Vítor H. Nascimento⁴  Carlos A. Prete⁴  Neal Alexander⁵  Christopher Dye⁶  Tassila Salomon⁷  Maria do P. S. S. Carvalho⁸  Nelson A. Fraiji⁸  Claudia M. M. Abrahim⁸  Allyson G. da Costa⁸  Myuki A. E. Crispim⁸  Charles Whittaker⁹  Renata Buccheri^1,10  Michael P. Busch^1,11  Eduard Grebe^1,12 

[1] Center of Mathematics, Computing and Cognition, Universidade Federal do ABC, Rua Arcturus, 03, São Bernardo do Campo, Brasil;Departamento de Moléstias Infecciosas e Parasitarias, Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, Av Dr Eneas de Carvalho 470, 1º andar, 05403-000, São Paulo, Brazil;Departamento de Moléstias Infecciosas e Parasitarias, Instituto de Medicina Tropical da Faculdade de Medicina da Universidade de São Paulo, Av Dr Eneas de Carvalho 470, 1º andar, 05403-000, São Paulo, Brazil;MRC Centre for Global Infectious Disease Analysis, and the Abdul Latif Jameel Institute for Disease and Emergency Analytics (J-IDEA), School of Public Health, Imperial College London, South Kensington Campus, SW7 2AZ, London, UK;Department of Zoology, University of Oxford, South Parks Road, OX1 3SZ, Oxford, UK;Department of Electronic Systems Engineering, University of São Paulo, Av. Professor Luciano Gualberto, Travessa 3, 158, São Paulo, Brazil;Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, LSHTM, Keppel Street, WC1E 7HT, London, UK;Department of Zoology, University of Oxford, South Parks Road, OX1 3SZ, Oxford, UK;Faculdade de Ciências Médicas de Minas Gerais, Alameda Ezequiel Dias, 275, Belo Horizonte, Brazil;Fundação Hospitalar de Hematologia e Hemoterapia do Amazonas, Av. Constantino Nery, 4397, Manaus, Brazil;MRC Centre for Global Infectious Disease Analysis, and the Abdul Latif Jameel Institute for Disease and Emergency Analytics (J-IDEA), School of Public Health, Imperial College London, South Kensington Campus, SW7 2AZ, London, UK;Vitalant Research Institute, 270 Masonic Avenue, San Francisco, CA, USA;Vitalant Research Institute, 270 Masonic Avenue, San Francisco, CA, USA;University of California San Francisco, 1001 Potrero Ave, San Francisco, CA, USA;Vitalant Research Institute, 270 Masonic Avenue, San Francisco, CA, USA;University of California San Francisco, 1001 Potrero Ave, San Francisco, CA, USA;SACEMA, Stellenbosch University, 19 Jonkershoek Rd, Stellenbosch, South Africa;

关键词: COVID-19;    SARS-CoV-2;    Gamma;    P.1;    Reinfections;    Blood donors;    Herd immunity;    Manaus;    Amazon;    Brazil;   

DOI  :  10.1186/s12879-022-07094-y

来源: Springer

【 摘 要 】

BackgroundThe city of Manaus, north Brazil, was stricken by a second epidemic wave of SARS-CoV-2 despite high seroprevalence estimates, coinciding with the emergence of the Gamma (P.1) variant. Reinfections were postulated as a partial explanation for the second surge. However, accurate calculation of reinfection rates is difficult when stringent criteria as two time-separated RT-PCR tests and/or genome sequencing are required. To estimate the proportion of reinfections caused by Gamma during the second wave in Manaus and the protection conferred by previous infection, we identified anti-SARS-CoV-2 antibody boosting in repeat blood donors as a mean to infer reinfection.MethodsWe tested serial blood samples from unvaccinated repeat blood donors in Manaus for the presence of anti-SARS-CoV-2 IgG antibodies using two assays that display waning in early convalescence, enabling the detection of reinfection-induced boosting. Donors were required to have three or more donations, being at least one during each epidemic wave. We propose a strict serological definition of reinfection (reactivity boosting following waning like a V-shaped curve in both assays or three spaced boostings), probable (two separate boosting events) and possible (reinfection detected by only one assay) reinfections. The serial samples were used to divide donors into six groups defined based on the inferred sequence of infection and reinfection with non-Gamma and Gamma variants.ResultsFrom 3655 repeat blood donors, 238 met all inclusion criteria, and 223 had enough residual sample volume to perform both serological assays. We found 13.6% (95% CI 7.0–24.5%) of all presumed Gamma infections that were observed in 2021 were reinfections. If we also include cases of probable or possible reinfections, these percentages increase respectively to 22.7% (95% CI 14.3–34.2%) and 39.3% (95% CI 29.5–50.0%). Previous infection conferred a protection against reinfection of 85.3% (95% CI 71.3–92.7%), decreasing to respectively 72.5% (95% CI 54.7–83.6%) and 39.5% (95% CI 14.1–57.8%) if probable and possible reinfections are included.ConclusionsReinfection by Gamma is common and may play a significant role in epidemics where Gamma is prevalent, highlighting the continued threat variants of concern pose even to settings previously hit by substantial epidemics.

【 授权许可】

CC BY