Seasonal Influenza Vaccine Effectiveness, 2017-2018

Table. Description of patients by Race/ethnicity
Race Number % Total
White, non-Hispanic 6059 72
Black, non-Hispanic 658 8
Hispanic 881 10
Other, non-Hispanic 812 10

*Missing 53 cases

Table. Influenza virus type and subtype among influenza-positive patients
Virus Type Number % Total
Influenza A 2103 69
H3N2 1761 58
H1N1 318 10
Not subtyped 24 <1
Influenza B 958 31
B Yamagata 908 30
B Victoria 39 <1
Lineage not determined 11 <1

Rolfes et. AL, 2019

Table. Influenza vaccine effectiveness for all vaccine types, 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 3050 (42) 5386 (53) 38% (31 to 43)
6 mos–8 262 (28) 847 (57) 68% (55 to 77)
9–17 837 (31) 965 (39) 32% (16 to 44)
18–49 965 (33) 1894 (43) 33% (21 to 44)
50–64 571 (53) 937 (63) 30% (13 to 44)
≥65 415 (76) 743 (80) 17% (-14 to 39)
Table. Influenza vaccine effectiveness for all vaccine types, Influenza A viruses
Age group (years) Influenza positive
Total
Influenza positive
(% Vaccinated)
Influenza negative
Total
Influenza negative
(% Vaccinated)
Adjusted VE % Adjusted 95% CI
All ages 2103 (43) 5386 (53) 30% (22 to 38)
6 mos–8 217 (30) 847 (56) 64% (50 to 75)
9–17 575 (32) 965 (39) 28% (9 to 43)
18–49 688 (36) 1894 (43) 21% (4 to 35)
50–64 350 (58) 937 (63) 20% (-5 to 39)
≥65 273 (77) 743 (80) 11% (-28 to 38)
Table. Influenza vaccine effectiveness for all vaccine types, 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 1761 (45) 5386 (53) 22% (12 to 31)
6 mos–8 155 (36) 847 (56) 54% (33 to 69)
9–17 488 (35) 965 (39) 18% (-6 to 36)
18–49 581 (38) 1894 (43) 14% (-6 to 30)
50–64 298 (56) 937 (63) 21% (-5 to 41)
≥65 239 (77) 743 (80) 10% (-32 to 39)
Table. Influenza vaccine effectiveness for all vaccine types, Influenza A(H1N1)pdm09 viruses
Age group (years) Influenza positive Total Influenza positive (% Vaccinated) Influenza negative Total Influenza negative (% Vaccinated) Adjusted VE % Adjusted 95% CI
All ages 318 (29) 5386 (53) 62% (50 to 71)
6 mos–8 59 (12) 847 (56) 87% (71 to 95)
9–17 88 (17) 965 (39) 70% (46 to 67)
18–49 98 (28) 1894 (43) 48% (18 to 67)
50–64 40 (48) 937 (63) 36% (-23 to 67)
≥65 33 (75) 743 (80) 19% (-91 to 65)
Table. Influenza vaccine effectiveness for all vaccine types, Influenza B/Yamagata lineage viruses
Age group (years) Influenza positive Total Influenza positive (% Vaccinated) Influenza negative Total Influenza negative (% Vaccinated) Adjusted VE % Adjusted 95% CI
All ages 908 (41) 5386 (53) 48% (39 to 55)
6 mos–8 40 (25) 847 (56) 77% (49 to 90)
9–17  242 (31) 965 (39) 28% (1 to 48)
18-49 268 (25) 1894 (43) 56% (41 to 68)
50-64 216 (51) 937 (63) 42% (21 to 58)
≥165 142 (76) 743 (80) 26% (-17 to 53)
Table. Influenza vaccine effectiveness for all vaccine types, Influenza B/Victoria lineage viruses
Age group (years) Influenza positive Total Influenza positive (% Vaccinated) Influenza negative Total Influenza negative (% Vaccinated) Adjusted VE % Adjusted 95% CI
All ages 39 (21) 5386 (53) 76% (45 to 89)