How Switzerland Prevented Hundreds of HIV Diagnoses With PrEP — and Who Is Still Being Left Behind

A new analysis presented at HIV Drug Therapy Glasgow 2026 highlights the impact of Switzerland’s national PrEP strategy. But despite substantial progress, significant gaps remain, particularly among women and people with specific prevention needs.

GLASGOW, November 2026 — Switzerland’s efforts to expand access to HIV pre-exposure prophylaxis, or PrEP, appear to have delivered substantial public health benefits.

An analysis presented by Benjamin Hampel of the University of Zurich at HIV Drug Therapy Glasgow 2026 estimated that approximately 268 HIV diagnoses were averted during the study period following the implementation of PrEP.

Yet the findings also revealed a persistent challenge: the benefits of HIV prevention are not reaching everyone equally.

Women, in particular, remain significantly underrepresented among PrEP users in Switzerland.

A National Prevention Strategy Shows Results

Since 2019, Switzerland has implemented SwissPrEPared, a national observational study and prevention program designed to improve access to PrEP and the quality of HIV prevention services.

More than 10,000 people have participated in the program, which researchers estimate includes approximately 70 percent of all PrEP users in Switzerland.

In July 2024, another important milestone was reached when Switzerland’s mandatory health insurance system began covering PrEP and related healthcare services under specified conditions. The initial reimbursement arrangement is scheduled to continue until December 2026.

To evaluate the program’s impact, researchers combined information from three sources: Switzerland’s national mandatory HIV reporting system, SwissPrEPared, and the Swiss HIV Cohort Study.

They applied a difference-in-differences statistical model, comparing changes in HIV diagnoses among men who have sex with men (MSM), the population accounting for most PrEP use in Switzerland, with changes among heterosexual comparison groups.

The analysis also accounted for potential influences from the COVID-19 pandemic and migration associated with the war in Ukraine.

An Estimated 268 HIV Diagnoses Averted

The results suggest a substantial prevention effect.

Compared with the control group, the model estimated an average annual difference of 44.6 fewer HIV diagnoses among MSM during the post-intervention period.

When the analysis was restricted to Swiss MSM, the estimated annual difference was 37.6 fewer diagnoses.

Overall, researchers estimated that 268 HIV diagnoses were averted during the study period, with a 95 percent confidence interval ranging from 170.6 to 366.0.

Importantly, this figure represents a statistical estimate rather than a direct count of infections prevented.

The researchers compared observed trends with a modeled scenario of what might have occurred without the intervention.

Nevertheless, the findings provide evidence that the expansion of PrEP has contributed substantially to reducing HIV diagnoses in Switzerland.

The People HIV Prevention Is Missing

Despite these gains, the analysis identified important differences between people accessing PrEP and MSM newly diagnosed with HIV.

Among PrEP users, 58 percent had a university degree, compared with 30 percent of MSM newly diagnosed with HIV.

Swiss nationals were also more strongly represented among PrEP users, accounting for 54 percent compared with 44 percent in the comparison group.

These differences raise questions about how education, health literacy and structural barriers may influence access to HIV prevention.

The researchers also examined why some men had not initiated PrEP before receiving an HIV diagnosis.

A lack of perceived personal HIV risk was reported by 30 percent, while 23 percent cited insufficient awareness of PrEP.

These findings highlight a fundamental limitation of prevention programs: making an effective intervention available does not necessarily mean that everyone who could benefit from it will recognize their need for it or know how to access it.

Women Remain Underrepresented

The limited participation of women emerged as an additional concern during the discussion following the presentation.

Asked about the number of women accessing PrEP, Hampel acknowledged that their representation remained low.

According to his response, cisgender women accounted for approximately 1 to 2 percent of PrEP users. He suggested that uptake among transgender women was increasing, although the overall proportion of women remained below 5 percent.

Hampel acknowledged that more could be done to improve women’s representation.

The figures highlight a persistent imbalance in HIV prevention.

Although PrEP can provide effective HIV protection across different populations, its uptake in Switzerland remains concentrated among men who have sex with men.

The presentation did not provide a detailed analysis of the reasons for women’s low participation. Questions therefore remain about how to improve awareness, accessibility and the delivery of PrEP services for women.

Sex Work and Chemsex Highlight Additional Prevention Gaps

The study also examined characteristics associated with HIV diagnoses among participants in SwissPrEPared.

Men diagnosed with HIV within the program were more likely to report involvement in sex work and chemsex than those in the comparison group.

Sex work was reported by 32 percent compared with 8.5 percent, while chemsex was reported by 20 percent compared with approximately 9 percent.

These findings suggest that conventional PrEP delivery models may not fully address the needs of people in certain circumstances.

The researchers emphasized the importance of tailoring prevention services to people engaged in sex work and chemsex.

Long-acting PrEP options could become an important part of this approach, potentially offering greater flexibility for individuals who face challenges with daily oral medication or prefer alternative prevention methods.

However, further research will be needed to establish how effectively these approaches can address existing prevention gaps.

The Next Challenge for HIV Prevention

Switzerland’s experience demonstrates the potential impact of a coordinated national PrEP strategy.

The estimated reduction in HIV diagnoses among MSM represents an important public health achievement.

But the findings also show that success is not evenly distributed.

Women remain substantially underrepresented, while differences in education, risk perception and prevention needs continue to influence who accesses PrEP.

The researchers concluded that future strategies should expand beyond MSM to include other populations at risk of HIV, improve risk awareness particularly among younger MSM, and develop more tailored services for people engaged in sex work and chemsex.

The findings presented in Glasgow point toward a broader lesson for HIV prevention.

Scientific advances have made HIV prevention increasingly effective. The challenge now is ensuring that those advances reach the people who need them.

The next major gains may depend not only on developing better medicines, but also on making existing prevention options more accessible, inclusive and responsive to different communities.