US Flu VE Data for 2018-2019

Interim Estimates - MMWR

Reference: Unpublished Estimates Presented at the ACIP June 2019 meetingpdf icon

Description of patients enrolled in the US Flu VE Network, 2018-2019

Age
Age Number % Total
6 months-8 years 2434 24
9-17 years 1265 13
18-49 years 3266 32
50-64 years 1772 18
65+ years 1304 13
Gender
Gender Number % Total
Male 4033 40
Female 6008 60
Race/ethnicity
Race Number % Total
White, non-Hispanic 6872 68
Black, non-Hispanic 1142 11
Hispanic 948 9
Other, non-Hispanic 1024 10
Influenza virus type and subtype among influenza-positive patients, US Flu VE Network, 2018-2019
Virus Type Number % Total
Influenza A 2731 98
H3N2 1350 48
H1N1pdm09 1342 48
Not subtyped 48 15
Influenza B 64 2
B Yamagata 22 1
B Victoria 41 1
Lineage not determined 1 <1%

Influenza vaccine effectiveness for all vaccine types, 2018-19

Against influenza A or B viruses
Age group (years) Influenza positive
Total
Influenza positive
(% Vaccinated)
Influenza negative
Total
Influenza negative
(% Vaccinated)
Adjusted VE % Adjusted 95% CI
All ages 2795 48 7246 56 29% (21 to 35)
6 mos–8 759 40 1675 58 49% (38 to 58)
9–17 493 45 772 41 6% (-22 to 27)
18–49 831 39 2435 44 25% (10 to 37)
50–64 448 60 1324 62 12% (-12 to 31)
≥65 264 81 1040 83 12% (-29 to 41)
Influenza A(H1N1) viruses
Age group (years) Influenza positive
Total
Influenza positive
(% Vaccinated)
Influenza negative
Total
Influenza negative
(% Vaccinated)
Adjusted VE % Adjusted 95% CI
All ages 1342 (43) 7246 (56) 44% (36, 51)
Influenza A (H3N2) viruses
Age group (years) Influenza positive
Total
Influenza positive
(% Vaccinated)
Influenza negative
Total
Influenza negative
(% Vaccinated)
Adjusted VE % Adjusted 95% CI
All ages 1350 (52) 7246 (56) 9% (-4, 20)