End-of-season influenza vaccine effectiveness in adults and children, United Kingdom, 2016/17
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
The United Kingdom is in the fourth season of introducing
a universal childhood influenza vaccine programme.
The 2016/17 season saw early influenza
A(H3N2) virus circulation with care home outbreaks
and increased excess mortality particularly in those
65 years or older. Virus characterisation data indicated
emergence of genetic clusters within the
A(H3N2) 3C.2a group which the 2016/17 vaccine strain
belonged to. Methods: The test-negative case–control
(TNCC) design was used to estimate vaccine effectiveness
(VE) against laboratory confirmed influenza in
primary care. Results: Adjusted end-of-season vaccine
effectiveness (aVE) estimates were 39.8% (95%
confidence interval (CI): 23.1 to 52.8) against all influenza
and 40.6% (95% CI: 19.0 to 56.3) in 18–64-yearolds,
but no significant aVE in≥65-year-olds. aVE
was 65.8% (95% CI: 30.3 to 83.2) for 2–17-year-olds
receiving quadrivalent live attenuated influenza vaccine.
Discussion: The findings continue to provide support
for the ongoing roll-out of the paediatric vaccine
programme, with a need for ongoing evaluation. The
importance of effective interventions to protect the
≥65-year-olds remains.
a universal childhood influenza vaccine programme.
The 2016/17 season saw early influenza
A(H3N2) virus circulation with care home outbreaks
and increased excess mortality particularly in those
65 years or older. Virus characterisation data indicated
emergence of genetic clusters within the
A(H3N2) 3C.2a group which the 2016/17 vaccine strain
belonged to. Methods: The test-negative case–control
(TNCC) design was used to estimate vaccine effectiveness
(VE) against laboratory confirmed influenza in
primary care. Results: Adjusted end-of-season vaccine
effectiveness (aVE) estimates were 39.8% (95%
confidence interval (CI): 23.1 to 52.8) against all influenza
and 40.6% (95% CI: 19.0 to 56.3) in 18–64-yearolds,
but no significant aVE in≥65-year-olds. aVE
was 65.8% (95% CI: 30.3 to 83.2) for 2–17-year-olds
receiving quadrivalent live attenuated influenza vaccine.
Discussion: The findings continue to provide support
for the ongoing roll-out of the paediatric vaccine
programme, with a need for ongoing evaluation. The
importance of effective interventions to protect the
≥65-year-olds remains.
Date Issued
2017-11-02
Date Acceptance
2017-08-15
Citation
Eurosurveillance, 2017, 22 (44), pp.10-22
ISSN
1560-7917
Publisher
European Centre for Disease Prevention and Control
Start Page
10
End Page
22
Journal / Book Title
Eurosurveillance
Volume
22
Issue
44
Copyright Statement
This work is licensed under a Creative Commons Attribution 4.0 International License.
Subjects
Science & Technology
Life Sciences & Biomedicine
Infectious Diseases
A(H1N1) PDM09 STRAIN
DECREASED EFFECTIVENESS
STATES
VIRUS
A(H3N2)
CANADA
Publication Status
Published