tetano
Editor, Senior Moderator
Vaccines (Basel)
. 2020 Nov 12;8(4):E675.
doi: 10.3390/vaccines8040675.
Association between Exposure to Influenza Vaccination and COVID-19 Diagnosis and Outcomes
Pietro Ragni[SUP] 1 [/SUP], Massimiliano Marino[SUP] 1 [/SUP], Debora Formisano[SUP] 1 [/SUP], Eufemia Bisaccia[SUP] 2 [/SUP], Stefania Scaltriti[SUP] 2 [/SUP], Emanuela Bedeschi[SUP] 2 [/SUP], Roberto Grilli[SUP] 1 [/SUP]
Affiliations
Abstract
We explored whether influenza vaccination (IV) affects susceptibility to SARS-CoV-2 infection and clinical outcomes in COVID-19 patients in 17,608 residents of the Italian province of Reggio Emilia undergoing a SARS-CoV-2 test. Exposure to IV was ascertained and the strength of the association with SARS-CoV-2 positivity expressed with odds ratios (OR). Rates of hospitalisations and death in those found positive were assessed and hazard ratios (HR) were estimated. The prevalence of IV was 34.3% in the 4885 SARS-CoV-2 positive and 29.5% in the 12,723 negative subjects, but the adjusted OR indicated that vaccinated individuals had a lower probability of testing positive (OR = 0.89; 95% CI 0.80-0.99). Among the 4885 positive individuals, 1676 had received IV. After adjusting for confounding factors, there was no association between IV and hospitalisation (1.00; 95% CI 0.84-1.29) or death (HR = 1.14; 95% CI 0.95-1.37). However, for patients age ≥65 vaccinated close to the SARS-CoV-2 outbreak, HRs were 0.66 (95% CI: 0.44-0.98) and 0.70 (95% CI 0.50-1.00), for hospitalisation and death, respectively. In this study, IV was associated with a lower probability of COVID-19 diagnosis. In COVID-19 patients, overall, IV did not affect outcomes, although a protective effect was observed for the elderly receiving IV almost in parallel with the SARS-CoV-2 outbreak. These findings provide reassurance in planning IV campaigns and underscore the need for exploring further their impact on COVID-19.
Keywords: COVID-19; SARS-Cov-2; case-negative study; influenza vaccine; retrospective cohort study.
. 2020 Nov 12;8(4):E675.
doi: 10.3390/vaccines8040675.
Association between Exposure to Influenza Vaccination and COVID-19 Diagnosis and Outcomes
Pietro Ragni[SUP] 1 [/SUP], Massimiliano Marino[SUP] 1 [/SUP], Debora Formisano[SUP] 1 [/SUP], Eufemia Bisaccia[SUP] 2 [/SUP], Stefania Scaltriti[SUP] 2 [/SUP], Emanuela Bedeschi[SUP] 2 [/SUP], Roberto Grilli[SUP] 1 [/SUP]
Affiliations
- PMID: 33198368
- DOI: 10.3390/vaccines8040675
Abstract
We explored whether influenza vaccination (IV) affects susceptibility to SARS-CoV-2 infection and clinical outcomes in COVID-19 patients in 17,608 residents of the Italian province of Reggio Emilia undergoing a SARS-CoV-2 test. Exposure to IV was ascertained and the strength of the association with SARS-CoV-2 positivity expressed with odds ratios (OR). Rates of hospitalisations and death in those found positive were assessed and hazard ratios (HR) were estimated. The prevalence of IV was 34.3% in the 4885 SARS-CoV-2 positive and 29.5% in the 12,723 negative subjects, but the adjusted OR indicated that vaccinated individuals had a lower probability of testing positive (OR = 0.89; 95% CI 0.80-0.99). Among the 4885 positive individuals, 1676 had received IV. After adjusting for confounding factors, there was no association between IV and hospitalisation (1.00; 95% CI 0.84-1.29) or death (HR = 1.14; 95% CI 0.95-1.37). However, for patients age ≥65 vaccinated close to the SARS-CoV-2 outbreak, HRs were 0.66 (95% CI: 0.44-0.98) and 0.70 (95% CI 0.50-1.00), for hospitalisation and death, respectively. In this study, IV was associated with a lower probability of COVID-19 diagnosis. In COVID-19 patients, overall, IV did not affect outcomes, although a protective effect was observed for the elderly receiving IV almost in parallel with the SARS-CoV-2 outbreak. These findings provide reassurance in planning IV campaigns and underscore the need for exploring further their impact on COVID-19.
Keywords: COVID-19; SARS-Cov-2; case-negative study; influenza vaccine; retrospective cohort study.