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CMAJ
CMAJ
9711805
CMAJ : Canadian Medical Association Journal
0820-3946
1488-2329
CMA Impact Inc.

10.1503/cmaj.240906
196e1011
Practice
Five Things to Know about …
Respiratory syncytial virus vaccination in older adults
Killikelly April PhD
Siu Winnie MD MSc
Abrams Elissa M. MD MPH
Salvadori Marina I. MD
Centre for Immunization Programs (Killikelly, Siu, Abrams), Public Health Agency of Canada; School of Epidemiology and Public Health (Siu), Faculty of Medicine, University of Ottawa; Public Health Agency of Canada (Salvadori), Ottawa, Ont.
Correspondence to: April Killikelly, april.killikelly@phac-aspc.gc.ca
9 9 2024
09 9 2024
196 29 E1011E1011
© 2024 CMA Impact Inc. or its licensors
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY-NC-ND 4.0) licence, which permits use, distribution and reproduction in any medium, provided that the original publication is properly cited, the use is noncommercial (i.e., research or educational use), and no modifications or adaptations are made. See: https://creativecommons.org/licenses/by-nc-nd/4.0/
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pmcOlder adults are at increased risk of hospital admission, intensive care unit admission, and death due to respiratory syncytial virus (RSV)1

Most people experience mild RSV reinfections throughout their lifetime, particularly during respiratory virus season (November to March in Canada). People are at higher risk if they are older than 75 years or if they have comorbid conditions (e.g., pulmonary and cardiovascular conditions). In Canada, the rate of hospital admission related to RSV for adults aged 50 years and older is 16 per 100 000 people and increases to 63 per 100 000 for those aged 80 years and older.1

Vaccination against RSV prevents illness in older adults

In 2 randomized controlled trials of the 2 RSV vaccines available in Canada, vaccination prevented RSV-related lower respiratory tract illness (defined with slight differences in each trial) with efficacies of 66.7% (97% confidence interval [CI] 28.8%–85.8%) and 82.6% (97% CI 57.9%–94.1%), respectively, in adults aged 60 years and older.2,3

People aged 75 years and older and those with chronic medical conditions may benefit the most from RSV vaccination

Data from clinical trials and early postmarket surveillance after vaccination show a small increase in the incidence of neuroinflammatory events (e.g., Guillain–Barré syndrome).4 People aged 75 years and older who are frail or have chronic medical conditions are likely to have a favourable benefit despite this small potential risk.

Vaccination is recommended for those who are at increased risk of severe RSV disease

The National Advisory Committee on Immunization recommends RSV vaccination programs for adults aged 75 years and older, and adults aged 60 years and older who are residents of nursing homes and other chronic care facilities.5 Healthy adults older than 60 years may consider deferring vaccination until they are at higher risk of severe outcomes from RSV.

One dose of an RSV vaccine has been shown to offer protection against disease for at least 2 respiratory virus seasons6

Additional vaccine doses have been less successful at boosting immune responses in the short term, and the clinical significance of this is unclear. As RSV vaccination was introduced in Canada only in 2023, currently there are no recommendations on timing of a second dose.

Competing interests: Elissa Abrams is a board member of the Canadian Society of Allergy and Clinical Immunology and president of the Allergy Section of the Canadian Paediatric Society. No other competing interests were declared.

This article has been peer reviewed.
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References

1 Abrams E Doyon-Plourde P Davis P . Burden of disease of respiratory syncytial virus in older adults and adults considered at high risk of severe infection. medRxiv 2024 Mar. 19. doi: 10.1101/2024.03.18.24304476.
2 Walsh EE Pérez Marc G Zareba AM .; RENOIR Clinical Trial Group. Efficacy and safety of a bivalent RSV prefusion F vaccine in older adults. N Engl J Med 2023;388 :1465–77.37018468
3 Papi A Ison MG Langley JM .; AReSVi-006 Study Group. Respiratory syncytial virus prefusion F protein vaccine in older adults. N Engl J Med 2023;388 :595–608.36791160
4 Lloyd P . Evaluation of Guillain–Barré syndrome (GBS) following respiratory syncytial virus (RSV) vaccination among adults 65 years and older. Meeting of the Advisory Committee on Immunization Practices (ACIP) respiratory syncytial virus (RSV) vaccine, adults; 2024 June 26–28; Atlanta. Atlanta: Centers for Disease Control and Prevention.
5 National Advisory Committee on Immunization (NACI) statement on the prevention of respiratory syncytial virus (RSV) in older adults. Ottawa: Public Health Agency of Canada; 2024. Available: https://www.canada.ca/en/public-health/services/publications/vaccines-immunization/national-advisory-committee-immunization-statement-prevention-rsv-disease-older-adults.html (accessed 2024 Aug. 14).
6 Ison MG Papi A Athan E .; AReSVi-006 Study Group. Efficacy and safety of respiratory syncytial virus prefusion F protein vaccine (RSVPreF3 OA) in older adults over 2 RSV seasons. Clin Infect Dis 2024;78 :1732–44.38253338
