Vernazza writes that the publication was primarily aimed at Swiss physicians, informing them that it was about time to discuss new data on infectiousness with patients. Problematic differences in prevention messages were already being observed by the Commission: some physicians openly discussed the very low risk of transmission on ART and reassured patients who said they had condomless sex with their steady partner, whereas others told HIV-positive patients under therapy that all condomless sex – even with their HIV-positive partner – was risky.
He says at the time it was clear that ART did, in fact, reduce the likelihood of transmission, but the Commission’s estimate on the magnitude of this risk was neither discussed with patients nor communicated widely. The Commission summarised the epidemiological and biological knowledge known at the time and concluded that the risk of transmission in a differing HIV status partnership where the positive partner was on fully suppressive ART can be considered negligible. The focus of the paper was on how to communicate this information with an affected partnership where one partner was HIV positive.
Summarising the past eight years, Vernazza says one randomised and two on-going observational trials continue to support the “no-risk” hypothesis of the Swiss statement, while the basis for the statement – the absence of observed cases – has further increased over time. He points out that since this was a hot topic since its publication, one might expect an even higher degree of scrutiny amongst physicians to investigate and publish suspected cases compared with the years before 2008. Therefore, he notes, a further lack of documented cases should be even more convincing than it was in 2008.
But still, he writes, some authorities such as the US Centres for Disease Control and Prevention (CDC) remain reluctant to consider condomless sex with a partner under fully suppressive ART to be safe enough to recommend that clinicians openly discuss this option with their patients. In fact, he says, the CDC even proposed that HIV-negative individuals with HIV-positive steady partners should not only use condoms but should also be offered pre-exposure prophylaxis (PrEP) as an additional safeguard. The recommendation comes without a calculation of the number and cost to prevent a single case of HIV infection.
Vernazza writes that there were three key issues that motivated the publication of the Swiss statement in 2008, criminalisation, conception, and the conviction that it was ethical to engage patients in shared decision making. And, he notes, the positive effects of the statement have exceeded the Commission’s expectations, both in terms of geography and impact.
Until 2008, Switzerland was one of the countries with the highest numbers of convictions for perceived or potential HIV exposure. The effect of the statement was so convincing that Geneva’s deputy public prosecutor, Yves Bertossa, called for a revisit of an HIV exposure prosecution after reading about the Swiss statement. The Geneva Court of Justice subsequently quashed the conviction and there have been no further reports of prosecutions for HIV exposure since the ruling.
Furthermore, the Swiss statement has influenced other expert groups to produce statements that have impacted criminal law policy in some jurisdictions, including Canada, England, Wales and Scotland and Sweden. Despite this, the number of jurisdictions that recognise the prevention benefit of treatment in a criminal law context is still frustratingly low. Vernazza says: “We hope that other experts in HIV science, public health and law around the world will live up to their professional and ethical responsibilities to assist those in the criminal justice system to understand and interpret current medical and scientific evidence regarding HIV and take similar action.”
The second positive development in Switzerland after the statement, he says, was the “normalisation” of conception in Swiss HIV-serodiscordant couples. Swiss patients and their partners learned rapidly that there was no relevant risk of transmission under optimal treatment, thus the need for artificial reproductive technology to conceive a child was no longer an issue for fertile couples. As a consequence, reproductive assistance has not further been used in Switzerland after the statement which was well supported by Swiss physicians and experts in HIV prevention in Switzerland. He says numerous affected couples have now conceived naturally in Switzerland. In contrast, in neighbouring countries where an official declaration on transmission risk is still lacking, reproductive centres still offer insemination with processed semen, sometimes at high cost, meaning that the reproductive rights of people living with HIV are sometimes not achieved.
Vernazza notes that the Swiss statement has also empowered clinicians and other healthcare workers around the world to talk honestly and openly with their patients about the prevention benefit of ART. In 2013, consolidated HIV treatment and prevention guidelines from the World Health Organisation recognised for the first time the additional HIV prevention effect of ART. Subsequently, the International AIDS Society produced guidance influenced by the pragmatism and honesty of the Swiss statement to help healthcare workers counsel their patients with better understanding and greater clarity on the treatment and prevention benefits of ART.
But, Vernazza writes, perhaps the most important legacy of the Swiss statement has been the empowerment of people living with HIV. In 2009, at an international technical consultation on “positive prevention” convened by the Global Network of People Living with HIV/AIDS (GNP+) and UNAIDS, a new rights-based programme was conceived: “Positive Health, Dignity and Prevention (PHDP)”. Before this, many “positive prevention” programmes had placed an undue burden of responsibility for HIV transmission on HIV-positive people. PHDP shifts the focus of preventing HIV transmission to a shared responsibility of all individuals irrespective of HIV status. Central to this are evidence-informed, human-rights-based policies and programmes that support individuals living with HIV to make choices that address their needs and allow them to live healthy lives free from stigma and discrimination, such as those implemented in Switzerland following the Swiss statement.
He says these positive benefits should never be underestimated in the efforts to end the dual epidemics of HIV and HIV-related stigma.Full Swiss Medical Weekly report