Skip to main content Accessibility help
×
Home

Effectiveness of influenza vaccination in the elderly in South Africa

  • A. van VUUREN (a1) (a2), P. RHEEDER (a2) (a3) and E. HAK (a4)

Summary

This study primarily aimed to estimate the association between influenza vaccination and the occurrence of hospitalization for acute respiratory or cardiovascular diseases, or all-cause death during the influenza season in an elderly population in South Africa. We conducted a nested case-control study using data from a cohort of 45 522 elderly members of a private medical funding organization during the moderate 2004 influenza season. In 1282 (2·8%) subjects the combined outcome occurred and the influenza vaccination rate in controls was 15·4%. After adjustments for measured confounders, vaccination was associated with a statistically significant reduction of 19% (95% confidence interval 3·1–32·9) in the combined outcome. Post-hoc sensitivity analysis of the potential impact of potential healthy user bias showed that confounding, if present, could have caused this finding. Our data were inconclusive regarding the benefits of influenza vaccination in elderly persons in South Africa and given the low vaccine uptake, long-term follow-up is warranted.

  • View HTML
    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      Effectiveness of influenza vaccination in the elderly in South Africa
      Available formats
      ×

      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      Effectiveness of influenza vaccination in the elderly in South Africa
      Available formats
      ×

      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      Effectiveness of influenza vaccination in the elderly in South Africa
      Available formats
      ×

Copyright

Corresponding author

*Author for correspondence: A. van Vuuren, Medihelp, PO Box 26004, Arcadia, 0007, South Africa. (Email: avanvuuren@medihelp.co.za)

References

Hide All
1. Nichol, KL, et al. Effectiveness of influenza vaccine in the community-dwelling elderly. New England Journal of Medicine 2007; 357: 13731381.
2. Hak, E, et al. Influence of high-risk medical conditions on the effectiveness of influenza vaccination among elderly members of 3 large managed-care organizations. Clinical Infectious Diseases 2002; 35: 370377.
3. Smith, NM, et al. Prevention and control of influenza. Recommendations of the Advisory Committee on Immunization Practices (ACIP) (http://www.cdc.gov/mmwr/preview/mmwrhtml/rr55e628a1.htm). Accessed 2 August 2008.
4. Martin, DJ, Schoub, BD. Benefit: cost evaluation of influenza vaccination in South Africa. Occupational Health SA 1997; 3: 2328.
5. Szucs, T. The socio-economic burden of influenza. Journal of Antimicrobial Chemotherapy 1999; 44 (Suppl. B): 1115.
6. Hak, E, et al. A nested case-control study of influenza vaccination was a cost-effective alternative to a full cohort analysis. Journal of Clinical Epidemiology 2004; 57: 875880.
7. Ernster, VL. Nested case-control studies. Preventive Medicine 1994; 23: 587594.
8. Pearce, N. What does the odds ratio estimate in a case-control study? International Journal of Epidemiology 1993; 22: 11891192.
9. Gross, PA, et al. The efficacy of influenza vaccine in elderly persons: a meta-analysis and review of the literature. Annals of Internal Medicine 1995; 123: 518527.
10. Rivetti, D, et al. Vaccines for preventing influenza in the elderly. Cochrane Review 2006. Issue no. 3. Art no.: CD004876. doi:10.1002/14651858.CDC004876.pub2.
11. Epidemiology Unit, Respiratory Virus Surveillance. National Institute for Communicable Diseases Annual Report, 2004, p. 38.
12. Nichol, KL, Wuorema, J, Von Sternberg, T. Benefits of influenza vaccination for low-, intermediate- and high-risk senior citizens. Archives of Internal Medicine 1998; 158: 17691776.
13. Hak, E, et al. Clinical effectiveness of influenza vaccination in persons younger than 65 years with high-risk medical conditions. Archives of Internal Medicine 2005; 165: 274280.
14. Hak, E, et al. Conventional influenza vaccination is not associated with complications in working-age patients with asthma or chronic obstructive pulmonary disease. American Journal of Epidemiology 2003; 157: 692700.
15. Nichol, KL, Baken, L, Nelson, A. Relation between influenza vaccination and outpatient visits, hospitalizations, and mortality in elderly persons with chronic lung disease. Annals of Internal Medicine 1999; 130: 397403.
16. Looijmans-Van den, Akker I, et al. Clinical effectiveness of first and repeat influenza vaccination in adult and elderly diabetic patients. Diabetes Care 2006; 29: 17711776.
17. Nordin, J, et al. Influenza vaccine effectiveness in preventing hospitalizations and deaths in persons 65 years or older in Minnesota, New York, and Oregon: Data from 3 Health Plans. Journal of Infectious Diseases 2001; 184: 665670.
18. Simonson, L, et al. Impact of influenza vaccination on seasonal mortality in the US elderly population. Archives of Internal Medicine 2005; 165: 265272.
19. Jefferson, T, et al. Efficacy and effectiveness of influenza vaccines in elderly people: a systematic review. Lancet 2005; 366: 11651174.
20. Jackson, LA, et al. Evidence of bias in estimates of influenza vaccine effectiveness in seniors. International Journal of Epidemiology 2006; 35: 337344.

Keywords

Effectiveness of influenza vaccination in the elderly in South Africa

  • A. van VUUREN (a1) (a2), P. RHEEDER (a2) (a3) and E. HAK (a4)

Metrics

Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed