tetano
Editor, Senior Moderator
Clin Infect Dis
. 2021 Jan 27;ciab060.
doi: 10.1093/cid/ciab060. Online ahead of print.
Effect of Vaccination on Preventing Influenza-Associated Hospitalizations Among Children During a Severe Season Associated with B/Victoria Viruses, 2019-2020
Angela P Campbell[SUP] 1 [/SUP], Constance Ogokeh[SUP] 1 2 [/SUP], Geoffrey A Weinberg[SUP] 3 [/SUP], Julie A Boom[SUP] 4 5 [/SUP], Janet A Englund[SUP] 6 [/SUP], John V Williams[SUP] 7 [/SUP], Natasha B Halasa[SUP] 8 [/SUP], Rangaraj Selvarangan[SUP] 9 10 [/SUP], Mary A Staat[SUP] 9 [/SUP], Eileen J Klein[SUP] 6 [/SUP], Monica McNeal[SUP] 11 [/SUP], Marian G Michaels[SUP] 7 [/SUP], Leila C Sahni[SUP] 4 5 [/SUP], Laura S Stewart[SUP] 8 [/SUP], Peter G Szilagyi[SUP] 3 12 [/SUP], Christopher J Harrison[SUP] 9 [/SUP], Joana Y Lively[SUP] 13 14 [/SUP], Brian Rha[SUP] 13 [/SUP], Manish Patel[SUP] 1 [/SUP]
Affiliations
Abstract
Background: The 2019-2020 influenza season was characterized by early onset with B/Victoria followed by A(H1N1)pdm09 viruses. Emergence of new B/Victoria viruses raised concerns about possible vaccine mismatch. We estimated vaccine effectiveness (VE) against influenza-associated hospitalizations and emergency department (ED) visits among U.S. children.
Methods: We assessed VE among children 6 months-17 years with acute respiratory illness and ≥10 days of symptoms enrolled at 7 pediatric medical centers in the New Vaccine Surveillance Network. Combined mid-turbinate/throat swabs were tested for influenza virus using molecular assays. Vaccination history was collected from parental report, state immunization information systems, and/or provider records. We estimated VE from a test-negative design using logistic regression to compare odds of vaccination among children testing positive versus negative for influenza.
Results: Among 2029 inpatients, 335 (17%) were influenza positive: 37% with influenza B/Victoria alone and 44% with influenza A(H1N1)pdm09 alone.VE was 62% (95% confidence interval [CI], 52%-71%) for influenza-related hospitalization, 54% (95% CI, 33%-69%) for B/Victoria viruses and 64% (95% CI, 49%-75%) for A(H1N1)pdm09. Among 2102 ED patients, 671 (32%) were influenza positive: 47% with influenza B/Victoria alone and 42% with influenza A(H1N1)pdm09 alone. VE was 56% (95% CI, 46%-65%) for an influenza-related ED visit, 55% (95% CI, 40%-66%) for B/Victoria viruses and 53% (95% CI, 37%-65%) for A(H1N1)pdm09.
Conclusions: Influenza vaccination provided significant protection against laboratory-confirmed influenza-associated hospitalizations and ED visits associated with the two predominantly circulating influenza viruses among children, including against the emerging B/Victoria virus subclade.
Keywords: Influenza; children; test negative design; vaccination.
. 2021 Jan 27;ciab060.
doi: 10.1093/cid/ciab060. Online ahead of print.
Effect of Vaccination on Preventing Influenza-Associated Hospitalizations Among Children During a Severe Season Associated with B/Victoria Viruses, 2019-2020
Angela P Campbell[SUP] 1 [/SUP], Constance Ogokeh[SUP] 1 2 [/SUP], Geoffrey A Weinberg[SUP] 3 [/SUP], Julie A Boom[SUP] 4 5 [/SUP], Janet A Englund[SUP] 6 [/SUP], John V Williams[SUP] 7 [/SUP], Natasha B Halasa[SUP] 8 [/SUP], Rangaraj Selvarangan[SUP] 9 10 [/SUP], Mary A Staat[SUP] 9 [/SUP], Eileen J Klein[SUP] 6 [/SUP], Monica McNeal[SUP] 11 [/SUP], Marian G Michaels[SUP] 7 [/SUP], Leila C Sahni[SUP] 4 5 [/SUP], Laura S Stewart[SUP] 8 [/SUP], Peter G Szilagyi[SUP] 3 12 [/SUP], Christopher J Harrison[SUP] 9 [/SUP], Joana Y Lively[SUP] 13 14 [/SUP], Brian Rha[SUP] 13 [/SUP], Manish Patel[SUP] 1 [/SUP]
Affiliations
- PMID: 33502489
- DOI: 10.1093/cid/ciab060
Abstract
Background: The 2019-2020 influenza season was characterized by early onset with B/Victoria followed by A(H1N1)pdm09 viruses. Emergence of new B/Victoria viruses raised concerns about possible vaccine mismatch. We estimated vaccine effectiveness (VE) against influenza-associated hospitalizations and emergency department (ED) visits among U.S. children.
Methods: We assessed VE among children 6 months-17 years with acute respiratory illness and ≥10 days of symptoms enrolled at 7 pediatric medical centers in the New Vaccine Surveillance Network. Combined mid-turbinate/throat swabs were tested for influenza virus using molecular assays. Vaccination history was collected from parental report, state immunization information systems, and/or provider records. We estimated VE from a test-negative design using logistic regression to compare odds of vaccination among children testing positive versus negative for influenza.
Results: Among 2029 inpatients, 335 (17%) were influenza positive: 37% with influenza B/Victoria alone and 44% with influenza A(H1N1)pdm09 alone.VE was 62% (95% confidence interval [CI], 52%-71%) for influenza-related hospitalization, 54% (95% CI, 33%-69%) for B/Victoria viruses and 64% (95% CI, 49%-75%) for A(H1N1)pdm09. Among 2102 ED patients, 671 (32%) were influenza positive: 47% with influenza B/Victoria alone and 42% with influenza A(H1N1)pdm09 alone. VE was 56% (95% CI, 46%-65%) for an influenza-related ED visit, 55% (95% CI, 40%-66%) for B/Victoria viruses and 53% (95% CI, 37%-65%) for A(H1N1)pdm09.
Conclusions: Influenza vaccination provided significant protection against laboratory-confirmed influenza-associated hospitalizations and ED visits associated with the two predominantly circulating influenza viruses among children, including against the emerging B/Victoria virus subclade.
Keywords: Influenza; children; test negative design; vaccination.