ORIGINAL ARTICLE

The potential epidemiological impact of a genital herpes vaccine for women

G P Garnett¹, G Dubin³, M Slaoui² and T Darcis²

¹ Department of Infectious Disease Epidemiology, Imperial College of Science, Technology and Medicine, St Mary’s Campus, Norfolk Place, London, UK
² GlaxoSmithKline Biologicals, Rixensart, Belgium
³ GlaxoSmithKline, King of Prussia, PA, USA

Correspondence to:
Correspondence to:
Professor Geoffrey Garnett
Department of Infectious Disease Epidemiology, Imperial College of Science, Technology and Medicine, St Mary’s Campus, Norfolk Place, London, UK; g.garnett{at}ic.ac.uk

Background: In two phase III vaccine trials immunisation of women previously uninfected by herpes simplex virus provided protection against genital herpes disease. In deciding policy, an evaluation of the epidemiological impact of the partial protection provided by the vaccine should be considered.

Methods: A sex and sexual activity stratified deterministic differential and partial differential equation model of the natural history of herpes simplex virus type 2 (HSV-2) and the impact of vaccination is developed and analysed. To explore the role of vaccination, the pattern of viral shedding and the transmission of infection during sexual acts within sexual partnerships are described.

Results: Using literature derived estimates of parameter values and assuming efficacy in only 40% of women the impact of the vaccine depends on assumptions made about its action. The vaccine has a limited impact if it only prevents disease but a more substantial impact if it reduces asymptomatic viral shedding, which it could do indirectly by preventing infection or directly by modifying the biology of the infection. Concern over the implications of a vaccine that prevents disease but has no impact on viral shedding was addressed in a worst case scenario. Here there is a modest increase in the incidence of infection in both men and women but an increase in disease prevalence in men alone, since the virus directly protects some women from disease.

Conclusions: Results suggest that a herpes vaccine should be used universally and that a vaccine that only protects HSV-1-/2- women can paradoxically have a significant epidemiological impact, the scale of which depends upon changes in patterns of viral shedding.

Keywords: HSV-2 epidemiology; genital herpes epidemiology; herpes vaccination; vaccination policy; mathematical modelling; targeting

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

• Herbst-Kralovetz, M. M., Pyles, R. B. (2006). Quantification of Poly(I:C)-Mediated Protection against Genital Herpes Simplex Virus Type 2 Infection.. J. Virol. 80: 9988-9997 [Abstract] [Full Text]  
• Rosenthal, S. L., Stanberry, L. R. (2005). Parental Acceptability of Vaccines for Sexually Transmitted Infections. Arch Pediatr Adolesc Med 159: 190-192 [Full Text]