Protocol of the Luebeck longitudinal investigation of SARS-CoV-2 infection (ELISA) study – a prospective population-based cohort study

Abstract

Background Considering the insufficiently controlled spread of new SARS-CoV-2 variants, partially low vaccination rates, and increased risk of a post-COVID syndrome, well-functioning, targeted intervention measures at local and national levels are urgently needed to contain the SARS-CoV-2 pandemic. Surveillance concepts (cross-sectional, cohorts, clusters) need to be carefully selected to monitor and assess incidence and prevalence at the population level. A critical methodological gap for identifying specific risks/dynamics for SARS-Cov-2 transmission and post-COVID-19-syndrome includes repetitive testing for past or present infection of a defined cohort with simultaneous assessment of symptoms, behavior, risk, and protective factors, as well as quality of life. Methods The ELISA-Study is a longitudinal, prospective surveillance study with a cohort approach launched in Luebeck in April 2020. The first part comprised regular PCR testing, antibody measurements, and a recurrent App-based questionnaire for a population-based cohort of 3000 inhabitants of Luebeck. The follow-up study protocol includes self-testing for antibodies and PCR testing for a subset of the participants, focusing on studying immunity after vaccination and/or infection and post-COVID-19 symptoms. Discussion The ELISA cohort and our follow-up study protocol will enable us to study the effects of a sharp increase of SARS-CoV-2 infections on seroprevalence of Anti-SARS-CoV-2 antibodies, post-COVID-19-symptoms, and possible medical, occupational, and behavioral risk factors. We will be able to monitor the pandemic continuously and discover potential sequelae of an infection long-term. Further examinations can be readily set up on an ad-hoc basis in the future. Our study protocol can be adapted to other regions and settings and is transferable to other infectious diseases. Trial registration DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00023418, Registered on 28 October 2020.

Estimates of protection against SARS-CoV-2 infection and severe COVID-19 in Germany before the 2022/2023 winter season - the IMMUNEBRIDGE project

“…From June to the end of November 2022 new survey rounds on vaccination status and previous infections were performed, blood samples were collected, and antibodies against SARS-Cov-2 were measured in four existing population-based cohort studies: the ELISA-Study (7, 14), MuSPAD (4), the German National Cohort (NAKO) (8), and STAAB (5). Four new cross-sectional studies were set up, one to provide regional depth (GUIDE Study; DRKS00029693) and three to provide relevant data on children (studies of the University Hospitals in Dresden (adolescents; DRKS00022549), Bochum (school children) (2), and Würzburg (pre-school children; Wü-Kita-CoV) (3)).…”

Progress in Biosensors for the Point-of-Care Diagnosis of COVID-19

“…The exact diagnosis can be based on various techniques and instruments, including the techniques locating damaged tissues such as tomography and sonography [ 29 , 30 , 31 ] and molecular biology methods such as polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) in their reverse transcriptase [ 32 , 33 , 34 , 35 , 36 , 37 , 38 ]. Immunochemical methods such as enzyme-linked immunosorbent assay (ELISA) for the detection of specific antibodies or the presence of the COVID antigen can also be used [ 39 , 40 , 41 , 42 ]. The mentioned methods generally exert good accuracy and reliability.…”

Transition to endemic: 2-year SARS-CoV-2 surveillance follow-up of the ELISA cohort

“…The secondary aim was to evaluate the relevance of antibodies against the nucleocapsid (NCP) antigen in discriminating immunisation from infection. The methods have been described previously elsewhere [ 4 ].…”