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Letter

Concerns for low coverage of influenza vaccination in middle-aged adults

, &
Pages 1989-1990 | Received 05 Jun 2013, Accepted 21 Jun 2013, Published online: 21 Jun 2013

Abstract

A survey in Hong Kong on middle-aged adults revealed a low influenza vaccination uptake rate of 13%. As a heterogeneous population comprising individuals at different levels of risk for complications, effective development of strategy for improving vaccination coverage in middle-aged adults should be prioritized.

To the editor

While the vulnerability of elderly people for influenza disease has been well established, parallel problem in middle-aged adults (between 50 and 64 y old) is less well appreciated. In the late 90s, American Academy of Family Physicians recommended lowering the age of routine influenza vaccination to 50, in view of their higher risk of complications from influenza.Citation1 Influenza-related hospitalization and mortality was reported to be substantial in an Australian study using data obtained between 1998 and 2005.Citation2 More recently from a global perspective, the high risk of death from influenza A (H1N1) was found to be similar between middle-age adults and the elderly (≥ 65).Citation3 In Hong Kong, for example, 41% of serious or fatal influenza occurred in middle-aged persons, compared with 17% in elderly, during the Winter season of 2010/11.Citation4 The incidence of severe disease was highest at age 51 to 60, despite a similar seroprevalence compared with younger people.Citation5 To protect public health, influenza vaccination is generally recommended for middle-aged adults, though the actual process, its acceptance and coverage vary across countries.Citation6,Citation7

In Hong Kong, the Government has recommended that people of age 50–64 receive influenza vaccination yearly, but unlike that for elderly there is no subsidy involved.Citation2 To determine the coverage of vaccination and its associated factors, we conducted a postal survey before the Winter influenza season in 2012 in one representative administrative district, targeting households with ≥ 1 adults aged 50–64. With an estimated response rate of 10.5%, the study enrolled 441 respondents, of which only 13% had received vaccination prior to the influenza season. As subsidy is not provided, it is not surprising that a majority (76%) was vaccinated at private clinics and full payment was made by 63% of the vaccinees. Respondents generally had a low perceived risk of influenza disease. The main factors associated with vaccination were an older age, being economically active, history of previous vaccination, chronic disease (). The low vaccination uptake has arisen from a relatively low perceived risk of influenza disease, and the demand for self-payment for a preventive measure that needs to be administered yearly. Understandably, there were subpopulations with underlying medical conditions, who would more likely see influenza as a health threat. Middle-aged adults do not constitute a uniform population with common characteristics, but can be roughly divided into 2 groups, some at a higher risk of complications from influenza and other at similar risk as the general population, or low risk. Our result of a 13% uptake was identical to that for lower risk middle-aged persons reported in a study in England, where 57% of higher risk persons had received the vaccination.Citation8

Table 1. Factor associated with receiving vaccination before the winter influenza season 2012/13 (n = 441)

Through modeling, studies in countries in Europe, United States and Australia had concluded that the vaccination of middle aged adults was generally cost-effective.Citation9-Citation12 While direct extrapolation of results from these models should be cautioned, the low uptake of influenza vaccine in middle-aged persons would nevertheless undermine efforts to prevent influenza infection and disease in the community. In the development of vaccination program, the heterogeneity of middle-aged population poses a challenge to public health authorities. Financial subsidy does not necessarily increase vaccination uptake if the self-perceived ‘lower risk’ sub-populations do not come forward for vaccination. New strategy is needed to boost uptake of middle-aged men and women in order to reduce population morbidity and slowing population spread of seasonal influenza virus.

Conflicts of interest

The authors declare that there are no conflicts of interest.

References

  • Zimmerman RK, American Academy of Family Physicians. Lowering the age for routine influenza vaccination to 50 years: AAFP leads the nation in influenza vaccine policy. Am Fam Physician 1999; 60:2061 - 6, 2069-70; PMID: 10569508
  • Newall AT, Wood JG, Macintyre CR. Influenza-related hospitalisation and death in Australians aged 50 years and older. Vaccine 2008; 26:2135 - 41; http://dx.doi.org/10.1016/j.vaccine.2008.01.051; PMID: 18325639
  • Van Kerkhove MD, Vandemaele KA, Shinde V, Jaramillo-Gutierrez G, Koukounari A, Donnelly CA, et al, WHO Working Group for Risk Factors for Severe H1N1pdm Infection. Risk factors for severe outcomes following 2009 influenza A (H1N1) infection: a global pooled analysis. PLoS Med 2011; 8:e1001053; http://dx.doi.org/10.1371/journal.pmed.1001053; PMID: 21750667
  • Scientific Committee on Vaccine Preventable Diseases. Recommendation on seasonal influenza vaccination for the 2011/2012 season. Hong Kong: Department of Health Centre for Health Protection, 2011.
  • Zhang AJ, To KK, Tse H, Chan KH, Guo KY, Li C, et al. High incidence of severe influenza among individuals over 50 years of age. Clin Vaccine Immunol 2011; 18:1918 - 24; http://dx.doi.org/10.1128/CVI.05357-11; PMID: 21900532
  • Centers for Disease Control and Prevention (CDC). Prevention and control of influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP)--United States, 2012-13 influenza season. MMWR Morb Mortal Wkly Rep 2012; 61:613 - 8; PMID: 22895385
  • Mereckiene J, Cotter S, D’Ancona F, Giambi C, Nicoll A, Levy-Bruhl D, et al, VENICE project gatekeepers group. Differences in national influenza vaccination policies across the European Union, Norway and Iceland 2008-2009. Euro Surveill 2010; 15:19700; PMID: 21087586
  • Joseph C, Elgohari S, Nichols T, Verlander N. Influenza vaccine uptake in adults aged 50-64 years: policy and practice in England 2003/2004. Vaccine 2006; 24:1786 - 91; http://dx.doi.org/10.1016/j.vaccine.2005.10.024; PMID: 16289767
  • Aballéa S, Chancellor J, Martin M, Wutzler P, Carrat F, Gasparini R, et al. The cost-effectiveness of influenza vaccination for people aged 50 to 64 years: an international model. Value Health 2007; 10:98 - 116; http://dx.doi.org/10.1111/j.1524-4733.2006.00157.x; PMID: 17391419
  • Aballéa S, De Juanes JR, Barbieri M, Martin M, Chancellor J, Oyagüez I, et al. The cost effectiveness of influenza vaccination for adults aged 50 to 64 years: a model-based analysis for Spain. Vaccine 2007; 25:6900 - 10; http://dx.doi.org/10.1016/j.vaccine.2007.07.033; PMID: 17764790
  • Maciosek MV, Solberg LI, Coffield AB, Edwards NM, Goodman MJ. Influenza vaccination health impact and cost effectiveness among adults aged 50 to 64 and 65 and older. Am J Prev Med 2006; 31:72 - 9; http://dx.doi.org/10.1016/j.amepre.2006.03.008; PMID: 16777545
  • Newall AT, Scuffham PA, Kelly H, Harsley S, Macintyre CR. The cost-effectiveness of a universal influenza vaccination program for adults aged 50-64 years in Australia. Vaccine 2008; 26:2142 - 53; http://dx.doi.org/10.1016/j.vaccine.2008.01.050; PMID: 18343537

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