tetano
Editor, Senior Moderator
J Infect Public Health
. 2021 Feb 23;14(5):674-680.
doi: 10.1016/j.jiph.2021.02.003. Online ahead of print.
A comparative study between the incidence and epidemiological features of Influenza-Like Illness and laboratory-confirmed COVID-19 cases in the Italian epicenter (Lombardy)
Francesca Grosso[SUP] 1 [/SUP], Ambra Castrofino[SUP] 1 [/SUP], Gabriele Del Castillo[SUP] 1 [/SUP], Cristina Galli[SUP] 1 [/SUP], Sandro Binda[SUP] 1 [/SUP], Laura Pellegrinelli[SUP] 1 [/SUP], Laura Bubba[SUP] 1 [/SUP], Danilo Cereda[SUP] 2 [/SUP], Marcello Tirani[SUP] 2 [/SUP], Maria Gramegna[SUP] 2 [/SUP], Silvana Castaldi[SUP] 3 [/SUP], Elena Pariani[SUP] 4 [/SUP]
Affiliations
Abstract
Introduction: In Lombardy, the influenza surveillance system relies on sentinel physicians that weekly report data on the number of Influenza-Like Illness (ILI) and a part of them also collect nasopharyngeal samples for virologic analyses. This study aims at comparing the ILI incidence of 2019-2020 influenza season with the incidence of COVID-19 cases in order to better understand the current epidemic and to evaluate whether the implementation of ILI surveillance system could succeed in early detection and monitoring of COVID-19 diffusion.
Methods: The distribution of ILI cases in the seasons 2017-2018, 2018-2019 and 2019-2020 was taken in consideration and the curve trends were compared and analyzed according to geographical areas, age groups and time differences.
Results: The curve trends presented a similar pattern up to the 9th week; in fact, a reduction in the ILI incidence rate was observed in the 2017-2018 and 2018-2019 season but in the 2019-2020 an increase in the reported ILI emerged. The relation between the numbers reported by 2019-2020 ILI surveillance and those reported for COVID-19 is supported by the curve trends, the correspondence between age groups, the correspondence by geographical location, and also by the results of the nasopharyngeal swab tests performed.
Discussion: The influenza surveillance system is an effective tool for early detection of COVID-19. It may provide timely and high-quality data evaluating the SARS-CoV-2 burden among population with ILI. Implementation of the system has to be prioritized in order to identify any future novel respiratory pathogen with pandemic potential.
Keywords: Influenza-Like Illness; Laboratory-confirmed COVID-19; SARS-CoV-2 epidemic; Surveillance of influenza.
. 2021 Feb 23;14(5):674-680.
doi: 10.1016/j.jiph.2021.02.003. Online ahead of print.
A comparative study between the incidence and epidemiological features of Influenza-Like Illness and laboratory-confirmed COVID-19 cases in the Italian epicenter (Lombardy)
Francesca Grosso[SUP] 1 [/SUP], Ambra Castrofino[SUP] 1 [/SUP], Gabriele Del Castillo[SUP] 1 [/SUP], Cristina Galli[SUP] 1 [/SUP], Sandro Binda[SUP] 1 [/SUP], Laura Pellegrinelli[SUP] 1 [/SUP], Laura Bubba[SUP] 1 [/SUP], Danilo Cereda[SUP] 2 [/SUP], Marcello Tirani[SUP] 2 [/SUP], Maria Gramegna[SUP] 2 [/SUP], Silvana Castaldi[SUP] 3 [/SUP], Elena Pariani[SUP] 4 [/SUP]
Affiliations
- PMID: 33865059
- PMCID: PMC7901382
- DOI: 10.1016/j.jiph.2021.02.003
Abstract
Introduction: In Lombardy, the influenza surveillance system relies on sentinel physicians that weekly report data on the number of Influenza-Like Illness (ILI) and a part of them also collect nasopharyngeal samples for virologic analyses. This study aims at comparing the ILI incidence of 2019-2020 influenza season with the incidence of COVID-19 cases in order to better understand the current epidemic and to evaluate whether the implementation of ILI surveillance system could succeed in early detection and monitoring of COVID-19 diffusion.
Methods: The distribution of ILI cases in the seasons 2017-2018, 2018-2019 and 2019-2020 was taken in consideration and the curve trends were compared and analyzed according to geographical areas, age groups and time differences.
Results: The curve trends presented a similar pattern up to the 9th week; in fact, a reduction in the ILI incidence rate was observed in the 2017-2018 and 2018-2019 season but in the 2019-2020 an increase in the reported ILI emerged. The relation between the numbers reported by 2019-2020 ILI surveillance and those reported for COVID-19 is supported by the curve trends, the correspondence between age groups, the correspondence by geographical location, and also by the results of the nasopharyngeal swab tests performed.
Discussion: The influenza surveillance system is an effective tool for early detection of COVID-19. It may provide timely and high-quality data evaluating the SARS-CoV-2 burden among population with ILI. Implementation of the system has to be prioritized in order to identify any future novel respiratory pathogen with pandemic potential.
Keywords: Influenza-Like Illness; Laboratory-confirmed COVID-19; SARS-CoV-2 epidemic; Surveillance of influenza.