AUTHOR=Ferrante Pierpaolo 

TITLE=The first 2 years of COVID-19 in Italy: Incidence, lethality, and health policies

JOURNAL=Frontiers in Public Health

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2022.986743

DOI=10.3389/fpubh.2022.986743

ISSN=2296-2565

ABSTRACT=Background: The novel coronavirus disease 2019 (COVID-19) is an ongoing pandemic that was first recognized in China in December 2019. This paper aims to provide a detailed overview of the first two years of the pandemic in Italy.
Design and methods: Using the negative binomial distribution, the daily incidence of infections was estimated from the virus’s lethality and the moving-averaged deaths. The lethality of the original strain (estimated through national sero-surveys) was adjusted daily for age of infections, hazard ratios of virus variants and the cumulative distribution of vaccinated individuals. 
Results: From February 24, 2020, to February 28, 2022, there were 20,833,018 (20,728,924-20,937,375) cases distributed over five waves. The overall lethality rate was 0.73%, but daily it ranged from 2.78% (in the first wave) to 0.15% (in the last wave). The first two waves had the highest number of daily deaths (about 710) and the last wave showed the highest peak of daily infections (220,487). Restriction measures of population mobility strongly slowed the viral spread. During the second year of the pandemic, vaccines prevented 10,000,000 infections and 115,000 deaths. 
Conclusion: Almost 40% of COVID-19 infections have gone undetected, likely because they were asymptomatic or paucisymptomatic. Mobility restriction measures were an effective suppression strategy while distance learning and smart working were effective mitigation strategies. A massive test campaign made it possible to detect asymptomatic cases, especially among younger people. Despite the variants of concern, vaccines strongly reduced the pandemic impact on the healthcare system avoiding strong restriction measures.