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Rates of hospitalisation for herpes zoster may warrant vaccinating Indigenous Australians under 70

Meru Sheel, Frank H Beard, Aditi Dey, Kristine Macartney and Peter B McIntyre
Med J Aust 2017; 207 (9): 395-396. || doi: 10.5694/mja16.01468
Published online: 6 November 2017

Herpes zoster (HZ) is caused by reactivation of latent varicella zoster virus infection. The most common complication of HZ is post-herpetic neuralgia (PHN), which is often debilitating and refractory to treatment.1 The incidence of both HZ and PHN increases markedly with age.2 In November 2016, a vaccine for HZ was included in Australia’s National Immunisation Program (NIP) for all people aged 70, together with a 5-year catch-up program for those aged 71–79 years.3 The vaccine is cost-effective for people aged 70–79, but is registered for vaccinating people from age 50.3

Concerns have been raised by clinicians in Aboriginal and Torres Strait Islander (Indigenous) health care that the NIP age criterion does not take into account the special circumstances of Indigenous Australians. First, fewer than 2% of Indigenous Australians are 70 years or older, compared with 10% of the non-Indigenous population (Box). Second, vaccines for pneumococcal disease and influenza are funded for Indigenous people from a younger age (50 and 15 years respectively) than for non-Indigenous Australians (65 years).4

There are few published data on the incidence of HZ among Indigenous Australians; in particular, analyses of HZ-related general practice encounters have not reported Indigenous-specific data.2 We therefore compared data from the Australian Institute of Health and Welfare (AIHW) National Hospital Morbidity Database on the rates of HZ-related hospitalisations of Indigenous and non-Indigenous Australians during 2007–2011. We excluded Tasmanian and Australian Capital Territory data, as recommended by the AIHW for this period.5 Hospitalisations associated with HZ were identified by International Classification of Diseases, revision 10, Australian modification (ICD-10-AM) codes B02.0–B02.9, and classified as principal diagnoses if recorded in the primary diagnostic field. Mid-year population estimates were obtained from the Australian Bureau of Statistics. Age-specific hospitalisation rates, incidence rate ratios (IRRs), and 95% confidence intervals (CIs) were estimated by negative binomial regression in Stata 13.1 (StataCorp).

We identified 214 HZ-related (principal) hospitalisations of Indigenous people and 11 252 of non-Indigenous people (Box). Hospitalisation rates were similar for Indigenous and non-Indigenous people aged 70–79 years or over 80, but were significantly higher among Indigenous people in younger age groups. For people aged 60–69 years, the IRR was 1.77 (95% CI, 1.27–2.48); further, the confidence interval for the hospitalisation rate of Indigenous people aged 60–69 years (34 [95% CI, 22–50] per 100 000 population) overlapped that of the rate for non-Indigenous people aged 70–79 years (44.8 [95% CI, 43.1–46.5] per 100 000 population). The results were similar when hospitalisations for which HZ was recorded in any diagnostic field were analysed (data not shown).

Patients hospitalised for HZ are at the severe end of the disease spectrum, accounting for only 3% of all HZ cases.2,6 Nevertheless, our findings suggest that the burden of severe HZ among Indigenous Australians in their 60s is higher than for non-Indigenous Australians. This higher disease burden adds to other considerations that support reviewing the age criteria for funded zoster vaccination of Indigenous Australians.

Box – Hospitalisations for herpes zoster (principal diagnosis) of Indigenous and non-Indigenous Australians, 2007–2011

Age group

Indigenous Australians


Non-Indigenous Australians


Incidence rate ratio (95% CI)

Number, 2007–2011*

5-year population (% of Indigenous population)

Average annual hospitalisations per 100 000 population (95% CI)

Number, 2007–2011*

5 year population (% of non-Indigenous population)

Average annual hospitalisations per 100 000 population (95% CI)


0–49 years

110

2 687 761 (87.6%)

4.1 (3.3–5.1)

1553

68 660 660 (68.1%)

2.3 (2.1–2.5)

1.81 (1.46–2.24)

50–59 years

34

218 589 (7.1%)

16 (11–22)

1071

12 819 945 (12.7%)

8.3 (7.4–9.4)

1.87 (1.29–2.71)

60–69 years

35

104 776 (3.4%)

34 (22–50)

1804

9 581 725 (9.5%)

18.8 (17.9–19.8)

1.77 (1.27–2.48)

70–79 years

16

42 995 (1.4%)

37 (18–79)

2631

5 877 963 (5.8%)

44.8 (43.1–46.5)

0.83 (0.51–1.36)

≥ 80 years

19

14 315 (0.5%)

132 (67–262)

3390

3 825 213 (3.8%)

89.8 (48.7–166)

1.47 (0.57–3.78)

All ages

214

3 068 436

7.0 (5.5–8.8)

11 252

100 765 506

11.2 (10.6–11.7)

0.62 (0.53–0.73)


* Age-specific hospitalisations (ICD-10-AM codes B02.0–B02.9) in New South Wales, Victoria, Queensland, Western Australia, South Australia and the Northern Territory. † Ratio of hospitalisation rates for Indigenous v non-Indigenous Australians.

Received 22 December 2016, accepted 20 February 2017

  • Meru Sheel1,2
  • Frank H Beard1,3
  • Aditi Dey1,3
  • Kristine Macartney1,3
  • Peter B McIntyre1,3

  • 1 National Centre for Immunisation Research and Surveillance, the Children's Hospital at Westmead, Sydney, NSW
  • 2 National Centre for Epidemiology and Population Health, Australian National University, Canberra, ACT
  • 3 University of Sydney, Sydney, NSW


Acknowledgements: 

This work was supported by the National Centre for Immunisation Research and Surveillance. Meru Sheel is a scholar in the Master of Philosophy in Applied Epidemiology program at the Australian National University.

Competing interests:

No relevant disclosures.

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access_time 02:47, 6 December 2017
David Corbet, Jenny Royle

The Research Letter by Sheel et al (1) states that “Concerns have been raised by clinicians in Aboriginal and Torres Strait Islander health care that the National Immunisation Program age criterion does not take into account the special circumstances of Indigenous Australians”
 
As clinicians working in Aboriginal and Torres Strait Islander health care, who have written about this topic (2), we felt it is important to raise the following issues.

Zoster vaccine is registered (3) from 50 years of age, but is unfunded until 70. It is unaffordable to many, costing around $200. Due to a lower life-expectancy, many Aboriginal and Torres Strait Islander people will die before they are able to access the funded vaccination. Life expectancy for a male Aboriginal and Torres Strait Islander child born in 2012 is 69.1 years, and 73.7 years for females (4).

The article demonstrates the increased burden of zoster disease requiring hospitalisation in the 50-59 and 60-69 year age groups (1).

The zoster vaccine prevents a significant number of cases of shingles, reduces the severity of many cases, and reduces post herpetic neuralgia. Shingles is a preventable condition occurring in Aboriginal and Torres Strait Islander populations but we are denying many the opportunity to benefit from the vaccine which is not consistent with ‘Close the Gap’ strategies.

We welcome these research findings and support the call to re-evaluate the age criteria for zoster vaccination for Aboriginal and Torres Strait Islander peoples.

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1. Rates of hospitalisation for herpes zoster may warrant vaccinating Indigenous Australians under 70
Meru Sheel, Frank H Beard, Aditi Dey, Kristine Macartney and Peter B McIntyre
Med J Aust 2017; 207 (9): 395-396. || doi: 10.5694/mja16.01468

2. Calls for shingles vaccine program to cater for Aboriginal and Torres Strait Islander people. David Corbet and Jenny Royle, Croakey Health Blog, published Jan 04, 2017.
https://croakey.org/calls-for-shingles-vaccine-program-to-cater-for-aboriginal-and-torres-strait-islander-people/

3. NCIRS Fact Sheet: August 2017. Accessed online 22/11/17.
 http://www.ncirs.edu.au/assets/provider_resources/fact-sheets/zoster-vaccine-fact-sheet.pdf

4. Estimates and Projections, Aboriginal and Torres Strait Islander Australians, 2001 to 2026. Australian Bureau of Statistics. LATEST ISSUE Released at 11:30 AM (CANBERRA TIME) 30/04/2014. Accessed online 22/11/17. http://www.abs.gov.au/ausstats/abs@.nsf/Products/6694405ADBF2B03BCA257CC9001439A6?opendocument

Competing Interests: No relevant disclosures.

Dr David Corbet
Surfcoast Medical Centre

Dr Jenny Royle
NEST Family Clinic

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