: Background: Reinfections occur as a response to natural infections wanes and novel strains of SARS-CoV-2 emerge. The present research explored the correlation between sex, age, COVID-19 vaccination, prior infection hospitalization, and SARS-CoV-2 reinfection in Sicily, Italy. Materials and Methods: A population-based retrospective cohort study was articulated using the vaccination flux from a regional registry and the Sicilian COVID-19 monitoring system of the Italian Institute of Health. Only adult Sicilians were included in the study, and hazard ratios were calculated using Cox regression. Results: Partial vaccination provided some protection (adj-HR: 0.92), when compared to unvaccinated individuals; furthermore, reinfection risk was reduced by full vaccination (adj-HR: 0.43), and the booster dose (adj-HR: 0.41). Males had a lower risk than females of reinfection with SARS-CoV-2 (adj-HR: 0.75). Reinfection with SARS-CoV-2 was diminished by hospitalization during the first infection (adj-HR: 0.78). Reinfection risk was higher among those aged 30-39 and 40-49 compared to those aged 18-29, whereas those aged 60-69, 70-79, and 80+ were statistically protected. Reinfection was significantly more frequent during the wild-type-Alpha, Delta, Delta-Omicron, and Omicron dominance/codominance waves compared to the wild type. Conclusions: This study establishes a solid base for comprehending the reinfection phenomenon in Sicily by pinpointing the most urgent policy hurdles and identifying some of the major factors. COVID-19 vaccination, one of the most effective public health tools, protects against reinfection, mostly caused by the Omicron strain. Elderly and hospitalized people's lower risk suggests stricter PPE use.

Maniscalco, L., Genovese, D., Ravazzolo, B., Vella, G., Sparacia, B., Vitale, F., et al. (2023). Low Risk of SARS-CoV-2 Reinfection for Fully or Boosted mRNA Vaccinated Subjects in Sicily: A Population-Based Study Using Real-World Data. VACCINES, 11(12) [10.3390/vaccines11121757].

Low Risk of SARS-CoV-2 Reinfection for Fully or Boosted mRNA Vaccinated Subjects in Sicily: A Population-Based Study Using Real-World Data

Maniscalco, Laura
Primo
;
Genovese, Dario;Ravazzolo, Barbara;Vella, Giuseppe;Sparacia, Benedetta;Vitale, Francesco;Matranga, Domenica;Amodio, Emanuele
Ultimo
2023-11-26

Abstract

: Background: Reinfections occur as a response to natural infections wanes and novel strains of SARS-CoV-2 emerge. The present research explored the correlation between sex, age, COVID-19 vaccination, prior infection hospitalization, and SARS-CoV-2 reinfection in Sicily, Italy. Materials and Methods: A population-based retrospective cohort study was articulated using the vaccination flux from a regional registry and the Sicilian COVID-19 monitoring system of the Italian Institute of Health. Only adult Sicilians were included in the study, and hazard ratios were calculated using Cox regression. Results: Partial vaccination provided some protection (adj-HR: 0.92), when compared to unvaccinated individuals; furthermore, reinfection risk was reduced by full vaccination (adj-HR: 0.43), and the booster dose (adj-HR: 0.41). Males had a lower risk than females of reinfection with SARS-CoV-2 (adj-HR: 0.75). Reinfection with SARS-CoV-2 was diminished by hospitalization during the first infection (adj-HR: 0.78). Reinfection risk was higher among those aged 30-39 and 40-49 compared to those aged 18-29, whereas those aged 60-69, 70-79, and 80+ were statistically protected. Reinfection was significantly more frequent during the wild-type-Alpha, Delta, Delta-Omicron, and Omicron dominance/codominance waves compared to the wild type. Conclusions: This study establishes a solid base for comprehending the reinfection phenomenon in Sicily by pinpointing the most urgent policy hurdles and identifying some of the major factors. COVID-19 vaccination, one of the most effective public health tools, protects against reinfection, mostly caused by the Omicron strain. Elderly and hospitalized people's lower risk suggests stricter PPE use.
26-nov-2023
Maniscalco, L., Genovese, D., Ravazzolo, B., Vella, G., Sparacia, B., Vitale, F., et al. (2023). Low Risk of SARS-CoV-2 Reinfection for Fully or Boosted mRNA Vaccinated Subjects in Sicily: A Population-Based Study Using Real-World Data. VACCINES, 11(12) [10.3390/vaccines11121757].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10447/621280
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