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Observational Study
. 2022 Jan 6;8(1):e30006.
doi: 10.2196/30006.

Individuals With SARS-CoV-2 Infection During the First and Second Waves in Catalonia, Spain: Retrospective Observational Study Using Daily Updated Data

Lia Alves-Cabratosa  1 , Marc Comas-Cufí  1 , Jordi Blanch  1 , Ruth Martí-Lluch  1   2 , Anna Ponjoan  1   2 , Antoni Castro-Guardiola  2   3   4 , Abelardo Hurtado-Ganoza  2   3 , Ana Pérez-Jaén  3 , Maria Rexach-Fumaña  2   3 , Delfi Faixedas-Brunsoms  5   6 , Maria Angels Gispert-Ametller  4   7 , Anna Guell-Cargol  7 , Maria Rodriguez-Batista  7 , Ferran Santaularia-Font  7 , Ramon Orriols  2   4   8   9   10 , Marc Bonnin-Vilaplana  2   4   8   9 , Juan Carlos Calderón López  2   4   8   9 , Gladis Sabater-Talaverano  2   4   8   9 , Francesc Xavier Queralt Moles  11 , Sara Rodriguez-Requejo  12   13 , Esteve Avellana-Revuelta  12   13 , Elisabet Balló  4   12 , Ester Fages-Masmiquel  12 , Josep-Maria Sirvent  14 , Carol Lorencio  14 , Josep Miquel Morales-Pedrosa  14 , Patricia Ortiz-Ballujera  14 , Rafel Ramos  1   2   4   12
Affiliations
Observational Study

Individuals With SARS-CoV-2 Infection During the First and Second Waves in Catalonia, Spain: Retrospective Observational Study Using Daily Updated Data

Lia Alves-Cabratosa et al. JMIR Public Health Surveill. .

Abstract

Background: A description of individuals with SARS-CoV-2 infection comparing the first and second waves could help adapt health services to manage this highly transmissible infection.

Objective: We aimed to describe the epidemiology of individuals with suspected SARS-CoV-2 infection, and the characteristics of patients with a positive test comparing the first and second waves in Catalonia, Spain.

Methods: This study had 2 stages. First, we analyzed daily updated data on SARS-CoV-2 infection in individuals from Girona (Catalonia). Second, we compared 2 retrospective cohorts of patients with a positive reverse-transcription polymerase chain reaction or rapid antigen test for SARS-CoV-2. The severity of patients with a positive test was defined by their admission to hospital, admission to intermediate respiratory care, admission to the intensive care unit, or death. The first wave was from March 1, 2020, to June 24, 2020, and the second wave was from June 25, 2020, to December 8, 2020.

Results: The numbers of tests and cases were lower in the first wave than in the second wave (26,096 tests and 3140 cases in the first wave versus 140,332 tests and 11,800 cases in the second wave), but the percentage of positive results was higher in the first wave than in the second wave (12.0% versus 8.4%). Among individuals with a positive diagnostic test, 818 needed hospitalization in the first wave and 680 in the second; however, the percentage of hospitalized individuals was higher in the first wave than in the second wave (26.1% versus 5.8%). The group that was not admitted to hospital included older people and those with a higher percentage of comorbidities in the first wave, whereas the characteristics of the groups admitted to hospital were more alike.

Conclusions: Screening systems for SARS-CoV-2 infection were scarce during the first wave, but were more adequate during the second wave, reflecting the usefulness of surveillance systems to detect a high number of asymptomatic infected individuals and their contacts, to help control this pandemic. The characteristics of individuals with SARS-CoV-2 infection in the first and second waves differed substantially; individuals in the first wave were older and had a worse health condition.

Keywords: COVID-19; SARS-CoV-2; comparison; epidemiology; pandemic; population characteristics; timeline; waves.

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Conflict of interest statement

Conflicts of Interest: None declared.

Figures

Figure 1
Figure 1
Comparison of the number and percentage of suspected and confirmed cases in the first (from March 1, 2020, to June 24, 2020) and second (from June 25, 2020, to December 8, 2020) SARS-CoV-2 waves in Girona (Catalonia).
Figure 2
Figure 2
Daily number of individuals with a positive and/or negative SARS-CoV-2 test in Girona (Catalonia) from March 1, 2020, to December 8, 2020.
Figure 3
Figure 3
Daily evolution of the empiric reproduction number (7 days; ρ7) and cumulative incidence rate (14 days; IA14) of positive cases in Girona (Catalonia), from March 1, 2020, to December 8, 2020.
Figure 4
Figure 4
Daily number of individuals with a positive SARS-CoV-2 test in hospital over time (from March 1, 2020, to December 8, 2020) in Girona (Catalonia).
See this image and copyright information in PMC

References

    1. Zorn CK, Pascual JM, Bosch W, Thiel DD, Francis D, Casler JD, Nassar A, Parkulo MA, Dunn AN, Waters TS, Hasse CH, Zargham B, Gross TL, Johnson CJ, Rigdon AW, Bruce CJ, Thielen KR. Addressing the Challenge of COVID-19: One Health Care Site's Leadership Response to the Pandemic. Mayo Clin Proc Innov Qual Outcomes. 2021 Feb;5(1):151–160. doi: 10.1016/j.mayocpiqo.2020.11.001. https://linkinghub.elsevier.com/retrieve/pii/S2542-4548(20)30258-7 S2542-4548(20)30258-7 - DOI - PMC - PubMed
    1. Weekly operational update on COVID-19 - 11 January 2021. World Health Organization. [2021-12-20]. https://www.who.int/publications/m/item/weekly-operational-update-on-cov... .
    1. Nacoti M, Ciocca A, Giupponi A, Brambillasca P, Lussana F, Pisano M, Goisis G, Bonacina D, Fazzi F, Naspro R. At the Epicenter of the Covid-19 Pandemic and Humanitarian Crises in Italy: Changing Perspectives on Preparation and Mitigation. NEJM Catalyst. [2021-12-20]. https://catalyst.nejm.org/doi/full/10.1056/CAT.20.0080 . - DOI
    1. Fanelli D, Piazza F. Analysis and forecast of COVID-19 spreading in China, Italy and France. Chaos Solitons Fractals. 2020 May;134:109761. doi: 10.1016/j.chaos.2020.109761. http://europepmc.org/abstract/MED/32308258 S0960-0779(20)30163-6 - DOI - PMC - PubMed
    1. Auener S, Kroon D, Wackers E, Dulmen SV, Jeurissen P. COVID-19: A Window of Opportunity for Positive Healthcare Reforms. Int J Health Policy Manag. 2020 Oct 01;9(10):419–422. doi: 10.34172/ijhpm.2020.66. http://europepmc.org/abstract/MED/32610730 - DOI - PMC - PubMed

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