Cost of HIV in Switzerland - A cost‐of‐illness analysis to quantify the economic and social impact of the HIV epidemic in Switzerland and its progress towards ending the epidemic

Abstract

Switzerland has achieved considerable progress in HIV care, with high treatment coverage and viral suppression among diagnosed people living with HIV. However, new infections continue to occur, and the remaining gap in the HIV care cascade is primarily related to diagnosis. In view of upcoming funding cuts, updated estimates of the lifetime economic burden of new HIV infections are needed to inform prevention policy, resource allocation, and progress towards UNAIDS and Swiss National Programme (NAPS) elimination targets. This cost-of-illness study estimated the lifetime direct medical and broader societal costs associated with one new HIV infection in Switzerland. We developed an incidence-based state-transition Markov model to simulate the lifetime progress through CD4 categories-defined health states of a newly infected person living with HIV in Switzerland. The model followed individuals in annual cycles across CD4 >500 cells/µL, CD4 200-500 cells/µL, CD4 <200 cells/µL, and death. Direct medical costs included antiretroviral therapy, outpatient visits, diagnostics and monitoring, and inpatient care. Indirect and broader societal costs included morbidity-related productivity losses, productivity losses due to premature mortality, depression-related costs, and monetised quality-adjusted life-year (QALY) losses. Costs were estimated using a bottom-up approach based on Swiss prices, tariffs, inpatient data, Swiss HIV Cohort Study inputs, Swiss mortality data, and published evidence. Future costs and outcomes were discounted at 3% annually. Sensitivity analyses examined the impact of discounting, age at infection, productivity assumptions, HIV utility ratios, and willingness-to-pay thresholds. A scenario analysis estimated the potential economic implications of reaching the UNAIDS diagnosis target of 95% in Switzerland. In the base case, the total lifetime cost of one new HIV infection in Switzerland was estimated at CHF 731,130. Direct medical costs accounted for CHF 289,584, while indirect and broader societal costs accounted for CHF 441,546. ART was the dominant direct cost component, amounting to CHF 258,224 and representing approximately 89% of direct medical costs. Other direct cost components were smaller: outpatient visits accounted for CHF 8,034, diagnostics for CHF 16,384, and inpatient care for CHF 6,942. Among indirect costs, productivity losses amounted to CHF 198,348, consisting of CHF 124,878 from morbidity-related paid work losses and CHF 73,469 from productivity losses due to premature mortality. Depression-related costs contributed CHF 3,198, while monetised QALY losses accounted for CHF 240,000. Sensitivity analyses showed that total lifetime costs ranged from CHF 611,130 under a lower willingness-to-pay threshold to CHF 1,192,145 in the undiscounted scenario. In the UNAIDS diagnosis scenario, increasing the diagnosed proportion from 93% to 95% was estimated to reduce the undiagnosed population by approximately 352 individuals. Depending on the transmission assumption applied, this corresponded to 24-70 avoided infections and potential lifetime cost savings of CHF 17.8-51.2 million. The lifetime economic burden of a new HIV infection in Switzerland is substantial and extends beyond direct medical costs. While ART is the main driver of direct medical costs, indirect and broader societal costs, particularly productivity losses and quality-of-life losses, account for a larger share of the total burden. These findings support sustained investment in HIV prevention, targeted testing, early diagnosis, and linkage to care. In the Swiss context, further progress towards UNAIDS and NAPS targets may generate meaningful long-term value by preventing new infections and avoiding lifetime medical and societal costs.