Modelling the potential impact of gonococcal vaccines
5th Asia Pacific Global Summit and Expo on Vaccines & Vaccination
July 27-29, 2015 Brisbane, Australia

Andrew P. Craiga, Richard T. Graya, Jennifer L. Edwardsb, Michael A. Apicellac, Michael P. Jenningsd, David P.Wilsona and Kate L. Seibd

Posters-Accepted Abstracts: J Vaccines Vaccin

Abstract:

Gonorrhoea, one of the most common sexually transmitted infections worldwide, can lead to serious sequelae, including infertility and increased HIV transmission. Recently, untreatable, multidrug-resistant Neisseria gonorrhoeae strains have been reported. In the absence of new antibiotics, and given the speed with which resistance has emerged to all previously used antibiotics, development of a vaccine would be the ideal solution to this public health emergency. Understanding the desired characteristics, target population, and expected impact of an anti-gonococcal vaccine is essential to facilitate vaccine design, assessment, and implementation. The modelling presented herein aims to fill these conceptual gaps and inform future gonococcal vaccine development. Using an individual-based, epidemiological simulation model, gonococcal prevalence was simulated in a heterosexual population of 100, 000 individuals (with a ~1.7% prevalence rate) after the introduction of vaccines with varied efficacy (10- 100%) and duration of protection (2.5-20 years). Model simulations predicted that gonococcal prevalence could be reduced by, at least, 90% after 20 years, if all 13-yearolds were given a vaccine with 50% efficacy that does not wane. A comparable reduction in prevalence could be achieved by a vaccine with 100% efficacy that wanes after 7.5 years. A 40% reduction in prevalence would be achieved with a non-waning vaccine of just 20% efficacy. A vaccine of moderate efficacy and duration could have a substantive impact on gonococcal prevalence and disease sequelae, if coverage is high and protection lasts over the highest risk period (i.e. most sexual partner change) among youths.