tetano
Editor, Senior Moderator
Clin Infect Dis
. 2022 Jul 22;ciac577.
doi: 10.1093/cid/ciac577. Online ahead of print.
Sustained within-season vaccine effectiveness against influenza-associated hospitalization in children: Evidence from the New Vaccine Surveillance Network, 2015-2016 through 2019-2020
Leila C Sahni[SUP] 1 2 [/SUP], Eric A Naioti[SUP] 3 [/SUP], Samantha M Olson[SUP] 3 [/SUP], Angela P Campbell[SUP] 3 [/SUP], Marian G Michaels[SUP] 4 [/SUP], John V Williams[SUP] 4 [/SUP], Mary Allen Staat[SUP] 5 [/SUP], Elizabeth P Schlaudecker[SUP] 5 [/SUP], Monica M McNeal[SUP] 5 [/SUP], Natasha B Halasa, Laura S Stewart[SUP] 6 [/SUP], James D Chappell[SUP] 6 [/SUP], Janet A Englund[SUP] 7 [/SUP], Eileen J Klein[SUP] 7 [/SUP], Peter G Szilagyi[SUP] 8 [/SUP], Geoffrey A Weinberg[SUP] 9 [/SUP], Christopher J Harrison, Rangaraj Selvarangan[SUP] 10 [/SUP], Jennifer E Schuster[SUP] 10 [/SUP], Parvin H Azimi[SUP] 11 [/SUP], Monica N Singer[SUP] 11 [/SUP], Vasanthi Avadhanula[SUP] 12 [/SUP], Pedro A Piedra[SUP] 1 12 [/SUP], Flor M Munoz[SUP] 1 2 12 [/SUP], Manish M Patel[SUP] 3 [/SUP], Julie A Boom[SUP] 1 2 [/SUP]
Affiliations
Abstract
Background: Adult studies have demonstrated within-season declines in influenza vaccine effectiveness (VE); data in children are limited.
Methods: We conducted a prospective, test-negative study of children 6 months-17 years hospitalized with acute respiratory illness at 7 pediatric medical centers during the 2015-2016 through 2019-2020 influenza seasons. Case-patients were children with an influenza-positive molecular test matched by illness onset to influenza-negative control-patients. We estimated VE [100% x (1 - odds ratio)] by comparing the odds of receipt of ≥1 dose of influenza vaccine ≥14 days before illness onset among influenza-positive children to influenza-negative children. Changes in VE over time between vaccination date and illness onset date were estimated using multivariable logistic regression.
Results: Of 8,430 children, 4,653 (55%) received ≥1 dose of influenza vaccine. On average, 48% were vaccinated through October and 85% through December each season. Influenza vaccine receipt was lower in case-patients than control-patients (39% vs. 57%, p < 0.001); overall VE against hospitalization was 53% (95% CI: 46%-60%). Pooling data across 5 seasons, the odds of influenza-associated hospitalization increased 4.2% (-3.2%-12.2%) per month since vaccination, with an average VE decrease of 1.9% per month (n = 4,000, p = 0.275). Odds of hospitalization increased 2.9% (95% CI: -5.4%-11.8%) and 9.6% (95% CI: -7.0%-29.1%) per month in children ≤8 years (n = 3,084) and 9-17 years (n = 916), respectively. These findings were not statistically significant.
Conclusions: We observed minimal, not statistically significant within-season declines in VE. Vaccination following current ACIP guidelines for timing of vaccine receipt remains the best strategy for preventing influenza-associated hospitalizations in children.
Keywords: case control; influenza; pediatrics; vaccination.
. 2022 Jul 22;ciac577.
doi: 10.1093/cid/ciac577. Online ahead of print.
Sustained within-season vaccine effectiveness against influenza-associated hospitalization in children: Evidence from the New Vaccine Surveillance Network, 2015-2016 through 2019-2020
Leila C Sahni[SUP] 1 2 [/SUP], Eric A Naioti[SUP] 3 [/SUP], Samantha M Olson[SUP] 3 [/SUP], Angela P Campbell[SUP] 3 [/SUP], Marian G Michaels[SUP] 4 [/SUP], John V Williams[SUP] 4 [/SUP], Mary Allen Staat[SUP] 5 [/SUP], Elizabeth P Schlaudecker[SUP] 5 [/SUP], Monica M McNeal[SUP] 5 [/SUP], Natasha B Halasa, Laura S Stewart[SUP] 6 [/SUP], James D Chappell[SUP] 6 [/SUP], Janet A Englund[SUP] 7 [/SUP], Eileen J Klein[SUP] 7 [/SUP], Peter G Szilagyi[SUP] 8 [/SUP], Geoffrey A Weinberg[SUP] 9 [/SUP], Christopher J Harrison, Rangaraj Selvarangan[SUP] 10 [/SUP], Jennifer E Schuster[SUP] 10 [/SUP], Parvin H Azimi[SUP] 11 [/SUP], Monica N Singer[SUP] 11 [/SUP], Vasanthi Avadhanula[SUP] 12 [/SUP], Pedro A Piedra[SUP] 1 12 [/SUP], Flor M Munoz[SUP] 1 2 12 [/SUP], Manish M Patel[SUP] 3 [/SUP], Julie A Boom[SUP] 1 2 [/SUP]
Affiliations
- PMID: 35867698
- DOI: 10.1093/cid/ciac577
Abstract
Background: Adult studies have demonstrated within-season declines in influenza vaccine effectiveness (VE); data in children are limited.
Methods: We conducted a prospective, test-negative study of children 6 months-17 years hospitalized with acute respiratory illness at 7 pediatric medical centers during the 2015-2016 through 2019-2020 influenza seasons. Case-patients were children with an influenza-positive molecular test matched by illness onset to influenza-negative control-patients. We estimated VE [100% x (1 - odds ratio)] by comparing the odds of receipt of ≥1 dose of influenza vaccine ≥14 days before illness onset among influenza-positive children to influenza-negative children. Changes in VE over time between vaccination date and illness onset date were estimated using multivariable logistic regression.
Results: Of 8,430 children, 4,653 (55%) received ≥1 dose of influenza vaccine. On average, 48% were vaccinated through October and 85% through December each season. Influenza vaccine receipt was lower in case-patients than control-patients (39% vs. 57%, p < 0.001); overall VE against hospitalization was 53% (95% CI: 46%-60%). Pooling data across 5 seasons, the odds of influenza-associated hospitalization increased 4.2% (-3.2%-12.2%) per month since vaccination, with an average VE decrease of 1.9% per month (n = 4,000, p = 0.275). Odds of hospitalization increased 2.9% (95% CI: -5.4%-11.8%) and 9.6% (95% CI: -7.0%-29.1%) per month in children ≤8 years (n = 3,084) and 9-17 years (n = 916), respectively. These findings were not statistically significant.
Conclusions: We observed minimal, not statistically significant within-season declines in VE. Vaccination following current ACIP guidelines for timing of vaccine receipt remains the best strategy for preventing influenza-associated hospitalizations in children.
Keywords: case control; influenza; pediatrics; vaccination.