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Clinical Trial
. 2022 Jan 24;19(3):1274.
doi: 10.3390/ijerph19031274.

Epidemiology of SARS-CoV-2 Infection in Italy Using Real-World Data: Methodology and Cohort Description of the Second Phase of Web-Based EPICOVID19 Study

Fulvio Adorni  1 , Nithiya Jesuthasan  1 , Elena Perdixi  1 , Aleksandra Sojic  1 , Andrea Giacomelli  2 , Marianna Noale  3 , Caterina Trevisan  4   5 , Michela Franchini  6 , Stefania Pieroni  6 , Liliana Cori  6 , Claudio Maria Mastroianni  7 , Fabrizio Bianchi  6 , Raffaele Antonelli-Incalzi  8 , Stefania Maggi  3 , Massimo Galli  2 , Federica Prinelli  1 , On Behalf Of The Epicovid Working Group
Affiliations
Clinical Trial

Epidemiology of SARS-CoV-2 Infection in Italy Using Real-World Data: Methodology and Cohort Description of the Second Phase of Web-Based EPICOVID19 Study

Fulvio Adorni et al. Int J Environ Res Public Health. .

Abstract

Digital technologies have been extensively employed in response to the SARS-CoV-2 pandemic worldwide. This study describes the methodology of the two-phase internet-based EPICOVID19 survey, and the characteristics of the adult volunteer respondents who lived in Italy during the first (April-May 2020) and the second wave (January-February 2021) of the epidemic. Validated scales and ad hoc questionnaires were used to collect socio-demographic, medical and behavioural characteristics, as well as information on COVID-19. Among those who provided email addresses during phase I (105,355), 41,473 participated in phase II (mean age 50.7 years ± 13.5 SD, 60.6% females). After a median follow-up of ten months, 52.8% had undergone nasopharyngeal swab (NPS) testing and 13.2% had a positive result. More than 40% had undergone serological test (ST) and 11.9% were positive. Out of the 2073 participants with at least one positive ST, 72.8% had only negative results from NPS or never performed it. These results indicate that a large fraction of individuals remained undiagnosed, possibly contributing to the spread of the virus in the community. Participatory online surveys offer a unique opportunity to collect relevant data at individual level from large samples during confinement.

Keywords: COVID-19; SARS-CoV-2; observational study; public health; self-reported data; testing; web-based survey.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Flow-chart of the participants in phase II EPICOVID19 survey.
Figure 2
Figure 2
Response rates by Italian region in the phase II survey. Darker coloured regions indicate higher response rates.
Figure 3
Figure 3
Frequency of self-reported symptoms by sex between March 2020 and February 2021 (n = 41,473) and p-values of the comparisons between females and males.
Figure 4
Figure 4
Distribution of positivity to SARS-CoV-2 by type of test performed in 4411 cases between March 2020 and February 2021 by sex. NPS: nasopharyngeal swab. ST: serological test.
See this image and copyright information in PMC

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