TABLE 3

Influenza VE for Prevention of Influenza A and B–Associated Hospitalizations Among Children by Using Documented Influenza Vaccination Status Supplemented by Parental Report, NVSN, 2018–2019


Influenza-Positive (Case Patients)Influenza-Negative (Control Patients)VE
No. Vaccinated/Total%No. Vaccinated/Total%VE, % (95% CI)Adjusteda VE, % (95% CI)
All influenza viruses
 All ages106/22647964/15666245 (27 to 58)41 (20 to 56)
  6 mo to <5 y54/10950730/11466444 (17 to 62)46 (19 to 64)
  5–17 y52/11744234/4205636 (4 to 58)23 (−23 to 51)
A(H3N2) viruses50/10846964/15666246 (20 to 63)41 (11 to 61)
A(H1N1)pdm09 viruses36/8343964/15666252 (25 to 69)47 (16 to 67)
  • a Adjusted for study site, age as a continuous variable, and calendar time (monthly intervals).