gms | German Medical Science

Introduction: Population-based surveillance as an additional component to existing sentinel surveillance systems of respiratory infections during the winter season is currently lacking in Germany. Here we assessed the feasibility of including population-based surveillance using frequent monitoring of asymptomatic and symptomatic participants rapid tests for respiratory infections in a sub-cohort of the German epidemic panel MuSPAD [1].

Methods: Participants of MuSPAD were recruited through e-mail and postal mail for self-register via the eResearch tool PIA. After registration and consent for study participation, participants received a package with rapid antigen tests for SARS-CoV-2, Influenza A/B and RSV for self-use (CorDx 4 in 1 Laien-Antigen Kombi-Test RS-Viren + Corona COVID-19 + Influenza A + B”; reported diagnostic accuracy by manufacturer: SARS-CoV-2: sensitivity 94.23%, specificity 100%; Influenza A: sensitivity 100%, specificity 99.82 %; Influenza B: sensitivity 98.90%, specificity 99.94%; RSV: sensitivity 99.82%, specificity 99.78%). Weekly self-sampling started in October 2023 and lasted until March 2024. Participants tested themselves on a weekly basis each Monday or Tuesday plus symptom reporting of ARI, as well as spontaneous reports of an ARI outside of this time-frame. Observed weekly proportions of positive tests in all participants with 95% confidence intervals adjusted for test performance were calculated by age and region and distributed in real-time to the public scientific dashboard (current URL: muspad.shinyapps.io/pcr4all/).

Preliminary results: Overall, 17,345 participants were invited and 2,000 self-registered by end of January 2024 of which 1,589 filled out the demographic questionnaire (median age: 54; 61% female). The SARS-CoV-2 positivity ranged from 0.13% (95% 0.02 – 0.76) in week 4 of 2024 to 4.88% (95% 3.82 – 6.22) in week 48 of 2023; Influenza A positivity ranged from 0.00% (95% 0.00 – 0.30) in week 47 of 2023 to 0.90% (95% 0.39 – 1.85) in week 3 of 2024; Influenza B positivity ranged from 0.00% (95% 0.00 – 1.43) in week 10 of 2024 to 0.95% (95% 0.37 – 2.28) in week 7 of 2024; RSV positivity ranged from 0.00% (95% 0.00 – 0.24) in week 3 of 2024 to 0.31% (95% 0.04 – 0.88) in week 48 of 2023.

Discussion: Adding population-based positivity of respiratory infections with continuous online reporting in a subcohort of MuSPAD was feasible. In comparison to sentinel surveillance, we found plausible positivity for SARS-CoV-2 but could not trace RSV and Influenza positivity well. We plan to use this data among other things to inform an ODE model for respiratory diseases to evaluate if weekly monitoring of symptomatic and asymptomatic individuals is a feasible surveillance technique.

The authors declare that they have no competing interests.

The authors declare that a positive ethics committee vote has been obtained.