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Estimating the critical immunity threshold for preventing hepatitis A outbreaks in men who have sex with men

  • D. G. REGAN (a1), J. G. WOOD (a2), C. BENEVENT (a3), H. ALI (a1), L. WATCHIRS SMITH (a1), P. W. ROBERTSON (a4), M. J. FERSON (a2) (a5), C. K. FAIRLEY (a6) (a7), B. DONOVAN (a1) (a8) and M. G. LAW (a1)...
Summary

Several outbreaks of hepatitis A in men who have sex with men (MSM) were reported in the 1980s and 1990s in Australia and other countries. An effective hepatitis A virus (HAV) vaccine has been available in Australia since 1994 and is recommended for high-risk groups including MSM. No outbreaks of hepatitis A in Australian MSM have been reported since 1996. In this study, we aimed to estimate HAV transmissibility in MSM populations in order to inform targets for vaccine coverage in such populations. We used mathematical models of HAV transmission in a MSM population to estimate the basic reproduction number (R 0) and the probability of an HAV epidemic occurring as a function of the immune proportion. We estimated a plausible range for R 0 of 1·71–3·67 for HAV in MSM and that sustained epidemics cannot occur once the proportion immune to HAV is greater than ~70%. To our knowledge this is the first estimate of R 0 and the critical population immunity threshold for HAV transmission in MSM. As HAV is no longer endemic in Australia or in most other developed countries, vaccination is the only means of maintaining population immunity >70%. Our findings provide impetus to promote HAV vaccination in high-risk groups such as MSM.

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Corresponding author
* Author for correspondence: Professor D. G. Regan, The Kirby Institute, UNSW Australia, Sydney, NSW 2052, Australia. (Email: dregan@kirby.unsw.edu.au)
References
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1. Gorgos, L. Sexual transmission of viral hepatitis. Infectious Disease Clinics of North America 2013; 27: 811836.
2. Nelson, NP, Murphy, TV. Hepatitis A: the changing epidemiology of hepatitis A. Clinical Liver Disease 2013; 2: 227230.
3. Australian Government Department of Health. National Notifiable Diseases Surveillance System (NNDSS) (http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-nndss-nndssintro.htm). Accessed 4 September 2015.
4. Ferson, MJ, Young, LC, Stokes, ML. Changing epidemiology of hepatitis A in the 1990s in Sydney, Australia. Epidemiology and Infection 1998; 121: 631636.
5. Stewart, T, Crofts, N. An outbreak of hepatitis A among homosexual men in Melbourne. Medical Journal of Australia 1993; 158: 519521.
6. Stokes, M-L, Ferson, MJ, Young, LC. Outbreak of hepatitis A among homosexual men in Sydney. American Journal of Public Health 1997; 87: 20392041.
7. Kani, J, et al. Hepatitis A virus infection among homosexual men. British Medical Journal 1991; 302: 13991399.
8. Schomer, K, et al. Hepatitis A among homosexual men – United States, Canada, and Australia. Journal of the American Medical Association 1992; 267: 15871588.
9. Heywood, AE, et al. Changes in seroprevalence to hepatitis A in Victoria, Australia: a comparison of three time points. Vaccine 2012; 30: 60206026.
10. Anderson, RM, May, RM. Infectious Diseases of Humans: Dynamics and Control. New York: Oxford University Press, 1991.
11. Gay, NJ, et al. Age-specific antibody prevalence to hepatitis A in England: implications for disease control. Epidemiology and Infection 1994; 113: 113120.
12. Hanna, JN, Hills, SL, Humphreys, JL. Impact of hepatitis A vaccination of Indigenous children on notifications of hepatitis A in north Queensland. Medical Journal of Australia 2004; 181: 482485.
13. Hull, BP, et al. Immunisation Coverage Annual Report, 2011. Communicable Diseases Intelligence 2013; 37: E291E312.
14. National Centre for Immunisation Research and Surveillance. Vaccine preventable diseases and vaccination coverage in Aboribinal and Torres Strait Islander people, Australia 2006–2010. Communicable Diseases Intelligence 2013; 37: S1S92.
15. Weerakoon, AP, et al. Immunity to hepatitis A when outbreaks of infection in men who have sex with men (MSM) are rare. Vaccine 2012; 30: 34303434.
16. Ali, H, et al. Increasing hepatitis A immunity in men who have sex with men in Sydney, 1996–2012. Vaccine. Published online: 26 January 2015. doi:10.1016/j.vaccine.2015.01.090.
17. Stokes, M-L. An outbreak of hepatitis A among homosexual men in Eastern Sydney, 1991–1992 (Master's Thesis). University of New South Wales, 1994.
18. Hollinger, FB, Martin, A. Hepatitis A virus. In: Knipe, DM, Howley, PM, eds. Fields Virology, 6th edn. New York: Lippincott Williams & Wilkins, 1990, pp. 550581.
19. Vynnycky, E, White, RG. An Introduction to Infectious Disease Modelling. New York: Oxford University Press, 2010.
20. Bauch, CT, et al. A dynamic model for assessing universal hepatitis A vaccination in Canada. Vaccine 2007; 25: 17191726.
21. Ciocca, M. Clinical course and consequences of hepatitis A infection. Vaccine 2000; 18 (Suppl. 1): S7174.
22. Delimar, N, et al. Epidemiological model of hepatitis A. Periodicum Biologorum 1993; 95: 409414.
23. Holmes, KK, et al. (eds). Sexually Transmitted Diseases, 4th edn. New York: McGraw-Hill, 2007.
24. Lemon, SM. The natural history of hepatitis A: the potential for transmission by transfusion of blood or blood products. Vox Sanguinis 1994; 67: 1923.
25. Van Effelterre, TP, et al. A mathematical model of hepatitis a transmission in the United States indicates value of universal childhood immunization. Clinical Infectious Diseases 2006; 43: 158164.
26. Phan, C, Hollinger, FB. Hepatitis A: natural history, immunopathogenesis, and outcome. Clinical Liver Disease 2013; 2: 231234.
27. Martin, A, Lemon, SM. Hepatitis A virus: from discovery to vaccines. Hepatology 2006; 43: S164S172.
28. Madeddu, D, et al. Estimating population distribution and HIV prevalence among homosexual and bisexual men. Sexual Health 2006; 3: 3743.
29. Poynten, IM, et al. Geographical clustering of anal cancer incidence in Australia. Sexual Health 2012; 9: 509512.
30. McLachlan, GJ, Peel, D. Finite Mixture Models. New York: Wiley-Interscience, 2000.
31. Saltelli, A, et al. Sensitivity Analysis In Practise: A Guide to Assessing Scientific Models. Chichester: Wiley, 2004.
32. Hoare, A, Regan, DG, Wilson, DP. Sampling and sensitivity analyses tools (SaSAT) for computational modelling. Theoretical Biology and Medical Modelling 2008; 5: 118.
33. Blower, SM, Dowlatabadi, H. Sensitivity and uncertainty analysis of complex models of disease transmission: an HIV model, as an example. International Statistical Review 1994; 62: 229243.
34. Australian Government Department of Health and Ageing. The Australian Immunisation Handbook, 10th edn, 2013 (http://www.health.gov.au/internet/immunise/publishing.nsf/Content/handbook10-4-4). Accessed 26 March 2015.
35. STIs in Gay Men Action Group (STIGMA). Australian sexually transmitted infection & HIV testing guidelines 2014 for asymptomatic men who have sex with men (http://stipu.nsw.gov.au/stigma/sti-testing-guidelines-for-msm/). Accessed 4 September 2015.
36. Centre for Social Research in Health in collaboration with The Kirby Institute. Gay periodic surveys (https://csrh.arts.unsw.edu.au/research/projects/gay-community-periodic-surveys/). Accessed 7 September 2015.
37. Donnelly, CA, et al. Serial intervals and the temporal distribution of secondary infections within households of 2009 pandemic influenza A (H1N1): implications for influenza control recommendations. Clinical Infectious Diseases 2011; 52: S123S130.
38. Farrington, CP, Kanaan, MN, Gay, NJ. Estimation of the basic reproduction number for infectious diseases from age-stratified serological survey data. Journal of the Royal Statistical Society: Series C (Applied Statistics) 2001; 50: 251292.
39. Hens, N. Inferring reproductive numbers from the final size epidemic data on hepatitis A in Flanders, Belgium: truncation, censoring and heterogeneity, 2011 (http://www2.warwick.ac.uk/fac/sci/statistics/crism/workshops/infer/talks/hens_et_al_infer_2011.pdf). Accessed 26 March 2015.
40. Jacobsen, K, Koopman, J. The effects of socioeconomic development on worldwide hepatitis A virus seroprevalence patterns. International Journal of Epidemiology 2005; 34: 600609.
41. Martinelli, D, et al. Control of hepatitis A by universal vaccination of children and adolescents: an achieved goal or a deferred appointment? Vaccine 2010; 28: 67836788.
42. Grulich, AE, et al. Sex in Australia: homosexual experience and recent homosexual encounters. Australian and New Zealand Journal of Public Health 2003; 27: 155163.
43. de Visser, RO, et al. Sex in Australia: heterosexual experience and recent heterosexual encounters among a representative sample of adults. Australian and New Zealand Journal of Public Health 2003; 27: 146154.
44. Australasian Sexual Health Alliance (ASHA). Australian STI management guidelines for use in primary care (http://www.sti.guidelines.org.au/resources/filter/item/hepatitis-a-2). Accessed 4 September 2015.
45. Storholm, ED, et al. Hepatitis vaccination of men who have sex with men at gay pride events. Prevention Science 2010; 11: 219227.
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