IN2 A Model-Based Estimation of the Cost-of-Illness Associated with Neisseria gonorrhoea in England and the USA: Assessing the Potential Impact of Antimicrobial Resistance and Long-Term Health Problems

Abstract

Both Neisseria gonorrhoeae (Ng) incidence and antimicrobial resistance (AMR) are increasing in England and the USA. Existing cost-of-illness analyses are limited, regarding quantification of AMR impact and long-term health consequences of Ng infection. We conducted a cost-of-illness study in these countries to specifically address these gaps. A Markov-model, using 2018 surveillance data, simulated Ng infections over a lifetime in three sexually-active cohorts aged 13-75 years: women, men-having-sex-with-men (MSM) and men-having-sex-with-women (MSW). A decision tree modelled the probabilities and costs of Ng infections and subsequent long-term health problems i.e., pelvic inflammatory disease (PID), infertility, human immunodeficiency virus (HIV) and prostate cancer, and AMR impact. All input parameters were from the literature. Discount rates of 3.5% (England) and 3% (USA) were applied. Scenarios explored varying AMR prevalence over time and AMR impact on long-term health problems. A total of 72,647 (England) / 988,396 (USA) Ng infections were estimated to occur over lifetime, with total discounted direct medical costs of £14,128,529 / $441,430,301 and an average cost per infection of £194 / $447. Women accounted for 55% / 69% of the total costs, with a higher average cost per infection of £293 / $807, versus £174 / $263 for MSM and £103 / $186 for MSW. Health-problems accounted for 52% / 72% of the total costs, with PID in women and HIV in MSM responsible for the majority of these costs. In AMR scenarios, total costs of up to £15,670,608 / $485,747,595 were estimated. Ng infections pose a substantial financial burden to healthcare systems, with the highest costs per infection observed in women. Differences in costs across countries are likely to be due to different healthcare systems. Given the expected rise in AMR, costs are likely to increase, underlining the need for prevention of Ng in both England and the USA.