tetano
Editor, Senior Moderator
J Pediatric Infect Dis Soc
. 2025 Jul 30
iaf069.
doi: 10.1093/jpids/piaf069. Online ahead of print. Effectiveness of cell culture-based influenza vaccine, 2023-2024
Huong Q Nguyen[SUP] 1 [/SUP], Oluwakemi D Alonge[SUP] 1 [/SUP], Kayla E Hanson[SUP] 1 [/SUP], Elisha Stefanski[SUP] 1 [/SUP], Joshua G Petrie[SUP] 1 [/SUP], Karita Ambrose[SUP] 2 [/SUP], Ashesh Ghandhi[SUP] 2 [/SUP], Adam Bissonnette[SUP] 1 [/SUP], Gregg C Sylvester[SUP] 2 [/SUP], Jennifer K Meece[SUP] 1 [/SUP], Edward A Belongia[SUP] 1 [/SUP]
Affiliations
Background: The cell culture-based inactivated influenza vaccine (ccIIV) was first approved for use in children aged 4 through 17 years in 2016 in the United States. The approved age indication for ccIIV was expanded to include children 6 months and older beginning the 2022-2023 season. There is limited real-world data on ccIIV effectiveness in children. We assessed ccIIV effectiveness using the test-negative design during the 2023-2024 season.
Methods: Patients aged 6 months through 64 years who sought outpatient or telehealth care for acute respiratory illness were actively recruited between October 2023 and May 2024. Symptom eligibility criteria included cough with illness duration ≤7 days. Respiratory samples were tested by RT-PCR to identify influenza cases. Vaccination dates and products were determined by immunization records. Analyses were restricted to ccIIV recipients and unvaccinated participants. ccIIV effectiveness was estimated as [100% X (1 - odds ratio)] for vaccination in cases versus test-negative controls, with adjustment for age and calendar time.
Results: Among 1850 participants, 12% were age 6 months through 3 years, 32% were age 4 through 17 years, and 56% were age 18 through 64 years. Influenza was detected in 505 (27%) participants; 267 had influenza A/H1N1pdm09, 149 had influenza B, 56 had influenza A/H3N2, and 33 had influenza A with unknown subtype. 470 (25%) received ccIIV. Among children (age 6 months through 17 years), ccIIV effectiveness was 64% [95% confidence interval (CI), 37%-81%] against influenza A/H1N1pdm09, 75% (95% CI, 43%-91%) against influenza B, and 76% (95% CI, 4%-97%) against influenza A/H3N2. Among adults (age 18 through 64 years), ccIIV effectiveness was 56% (95% CI, 31%-73%) against influenza A/H1N1pdm09, 62% (95% CI, 13%-86%) against influenza B, and 33% (95% CI, -62%-76%) against influenza A/H3N2. Young children aged 6 months through 3 years had the highest point estimates (88%-98%).
Conclusion: ccIIV generated substantial real-world effectiveness against medically attended, laboratory-confirmed influenza in children and adults during a season when influenza A/H1N1pdm09 viruses predominated and influenza B and influenza A/H3N2 co-circulated at lower levels.
Keywords: cell-based influenza vaccine; influenza; pediatric; vaccine effectiveness.
. 2025 Jul 30
iaf069.doi: 10.1093/jpids/piaf069. Online ahead of print. Effectiveness of cell culture-based influenza vaccine, 2023-2024
Huong Q Nguyen[SUP] 1 [/SUP], Oluwakemi D Alonge[SUP] 1 [/SUP], Kayla E Hanson[SUP] 1 [/SUP], Elisha Stefanski[SUP] 1 [/SUP], Joshua G Petrie[SUP] 1 [/SUP], Karita Ambrose[SUP] 2 [/SUP], Ashesh Ghandhi[SUP] 2 [/SUP], Adam Bissonnette[SUP] 1 [/SUP], Gregg C Sylvester[SUP] 2 [/SUP], Jennifer K Meece[SUP] 1 [/SUP], Edward A Belongia[SUP] 1 [/SUP]
Affiliations
- PMID: 40736196
- DOI: 10.1093/jpids/piaf069
Background: The cell culture-based inactivated influenza vaccine (ccIIV) was first approved for use in children aged 4 through 17 years in 2016 in the United States. The approved age indication for ccIIV was expanded to include children 6 months and older beginning the 2022-2023 season. There is limited real-world data on ccIIV effectiveness in children. We assessed ccIIV effectiveness using the test-negative design during the 2023-2024 season.
Methods: Patients aged 6 months through 64 years who sought outpatient or telehealth care for acute respiratory illness were actively recruited between October 2023 and May 2024. Symptom eligibility criteria included cough with illness duration ≤7 days. Respiratory samples were tested by RT-PCR to identify influenza cases. Vaccination dates and products were determined by immunization records. Analyses were restricted to ccIIV recipients and unvaccinated participants. ccIIV effectiveness was estimated as [100% X (1 - odds ratio)] for vaccination in cases versus test-negative controls, with adjustment for age and calendar time.
Results: Among 1850 participants, 12% were age 6 months through 3 years, 32% were age 4 through 17 years, and 56% were age 18 through 64 years. Influenza was detected in 505 (27%) participants; 267 had influenza A/H1N1pdm09, 149 had influenza B, 56 had influenza A/H3N2, and 33 had influenza A with unknown subtype. 470 (25%) received ccIIV. Among children (age 6 months through 17 years), ccIIV effectiveness was 64% [95% confidence interval (CI), 37%-81%] against influenza A/H1N1pdm09, 75% (95% CI, 43%-91%) against influenza B, and 76% (95% CI, 4%-97%) against influenza A/H3N2. Among adults (age 18 through 64 years), ccIIV effectiveness was 56% (95% CI, 31%-73%) against influenza A/H1N1pdm09, 62% (95% CI, 13%-86%) against influenza B, and 33% (95% CI, -62%-76%) against influenza A/H3N2. Young children aged 6 months through 3 years had the highest point estimates (88%-98%).
Conclusion: ccIIV generated substantial real-world effectiveness against medically attended, laboratory-confirmed influenza in children and adults during a season when influenza A/H1N1pdm09 viruses predominated and influenza B and influenza A/H3N2 co-circulated at lower levels.
Keywords: cell-based influenza vaccine; influenza; pediatric; vaccine effectiveness.