Can HIV epidemics among MSM be eliminated through participation in preexposure prophylaxis rollouts?

Abstract

To study the conditions under which PrEP coverage can eliminate HIV among men who have sex with men (MSM) in the Paris region.Design: Mathematical modeling. Methods:We propose an innovative approach, combining a transmission model with a game-theoretic model, for decision-making about PrEP use. Individuals at high risk of HIV infection decide to use PrEP, depending on their perceived risk of infection and the relative cost of using PrEP versus antiretroviral treatment (ART), which includes monetary and/or non-monetary aspects, such as price and access model of PrEP, consequences of being infected and lifelong ART.Results: If individuals assessed correctly their infection risk, and the cost of using PrEP were sufficiently low, then the PrEP rollout could lead to elimination. Specifically, assuming 86% PrEP effectiveness, as observed in two clinical trials, a minimum PrEP coverage of 55% (95% CI:43%-64%) among high-risk MSM would achieve elimination in the Paris region. A complete condom drop by MSM using PrEP slightly increases the minimum PrEP coverage required for elimination, by ~1%, while underestimation of their own HIV infection risk would require PrEP programs reduce the cost of using PrEP by a factor ~2 to achieve elimination. Conclusions: Elimination conditionsare not yet met in the Paris region, where at most 47% of high-risk MSM were using PrEP as of mid-2019. Further lowering the cost of PrEP and promoting a fair perception of HIV risk are required and should be maintained in the long run, to maintain elimination status.

Non-selective distribution of infectious disease prevention may outperform risk-based targeting

“…Among the latter, 4 are in the transition zone. Europe is in the high-efficacy region, in accordance with previous studies recommending risk-based distribution 5 , 37 . Notably, many communities in areas of active PrEP roll-out 38 are in the low-efficacy region: it is the case of Brazil and of those in southern Africa (excluding Botswana).…”

Preexposure Prophylaxis to Eliminate HIV in Taiwan by 2030: A Modeling Study

“…Even if risk compensation is 100% (all users stop using condoms), our modelling results still showed that such a decrease in condom use among those who use PrEP (which acts like a molecular condom) would, in fact, have a negligible effect on HIV epidemic control (Table 2A for stochastic modelling, and Table 4 for deterministic modelling). Jijón et al ( 2021) also reported similar results, indicating that risk compensation with none of the PrEP users using condom only minimally increase the PrEP coverage rate required for elimination 25 . Likewise, our study further revealed that the other two often-raised concerns for PrEP, imperfect (75%) adherence and occasional (1%) drug resistance, do not have a meaningful impact on the effect of a high-coverage PrEP program in eliminating the HIV epidemic among MSM.…”

“…Rapid, targeted, high-coverage roll-out of PrEP was associated with a rapid decline in new HIV diagnoses in New South Wales, Australia 23 . Modeling studies suggested that HIV elimination might be possible in the Netherlands and the Paris region with PrEP coverage rates of 82% and 55%, respectively 24,25 . However, the necessity, impact on achieving the WHO's goal to end the AIDS epidemic by 2030, and costeffectiveness of implementing a high-coverage PrEP program for HIV elimination have not yet been evaluated.…”

“…coverage rate, in the context of existing ART coverage, could theoretically eliminate HIV among MSM in the Netherlands24 . More recently,Jijón et al (2021) showed that a minimum PrEP coverage of 55%, which has yet to be achieved, could eliminate the HIV epidemic among high-risk MSM in the Paris region25 . In the current study, we employed stochastic modeling to demonstrate that, without a high-coverage PrEP program, the elimination of HIV in Taiwan remains unattainable.…”

Impact of voluntary testing on infectious disease epidemiology: A game theoretic approach

“…However, decisions made by individuals, within a given epidemiological context, have been typically described using mixed models, merging a game-theoretic model and an epidemic model [40,51,52]. Several topics have been addressed thus far: voluntary vaccination [42,50,[53][54][55][56][57][58][59][60][61][62][63][64], adoption of pre-exposure prophylaxis [65], social distancing [66][67][68] and self-isolation [69]. In fact, Hellmann and Thiele [69] modeled home testing as an aid in the decision making about whether or not to self-isolate.…”