Potential impact of vaccination against Neisseria meningitidis on Neisseria gonorrhoeae in the United States: results from a decision-analysis model.

Components in 4CMenB vaccine against Neisseria meningitidis serogroup B have shown to potentially cross-react with Neisseria gonorrhoeae. We modeled the theoretical impact of a US 4CMenB vaccination program on gonorrhea outcomes. A decision-analysis model was populated using published healthcare utilization and cost data. A two-dose adolescent vaccination campaign was assumed, with protective immunity starting at age 15 years and a base-case efficacy against gonorrhea of 20%. The 20%-efficacy level is an assumption since no clinical data have yet quantified the efficacy of 4CMenB against Neisseria gonorrhoea. Key outcome measures were reductions in gonorrhea and HIV infections, reduction in quality-adjusted life-years (QALYs) lost, and the economically justifiable price assuming a willingness-to-pay threshold of $75,000 per QALY gained. Adolescent vaccination with 4CMenB would prevent 83,167 (95% credible interval [CrI], 44,600-134,600) gonorrhea infections and decrease the number of HIV infections by 55 (95% CrI, 2-129) per vaccinated birth cohort in the USA. Excluding vaccination costs, direct medical costs for gonorrhea would reduce by $28.7 million (95% CrI, $6.8-$70.0 million), and income and productivity losses would reduce by $40.0 million (95% CrI, $8.2-$91.7 million). Approximately 83% of the reduction in lost productivity is generated by avoiding HIV infections. At a cost of $75,000 per QALY gained, and incremental to the vaccine's effect on meningococcal disease, a price of $26.10 (95% CrI, $9.10-$57.20) per dose, incremental to the price of the meningococcal vaccine, would be justified from the societal perspective. At this price, the net cost per infection averted would be $1,677 (95% CrI, $404-$2,564). Even if the cross-immunity of 4CMenB vaccine and gonorrhea is only 20%, the reduction in gonorrhea infections and associated costs would be substantial.