Risk of sexual transmission of HIV in the context of viral load suppression.

Background: In 2018, the Public Health Agency of Canada (PHAC) published a systematic review to calculate the risk of sexual transmission of human immunodeficiency virus (HIV) in the context of antiretroviral therapy (ART). In 2022, PHAC commissioned the Canadian Agency for Drugs and Technologies in Health (CADTH) to conduct a rapid review of evidence published since 2017. We undertook a meta-analysis of relevant studies from these two reviews. Methods: Studies from the rapid review that adequately assessed exposure (HIV viral load) and outcome (HIV seroconversion) were included and assessed for risk of bias (RoB) and certainty of evidence. Results were pooled to estimate the risk of HIV transmission per 100 person-years. Results: Three studies from the rapid review were eligible for inclusion and one was excluded after RoB assessment. In the remaining studies examining risk among people living with HIV who take ART and maintain a suppressed viral load (fewer than 200 copies/mL, measured every 4-6 months), no sexual transmissions of HIV were observed. The pooled incidence estimate based on these studies, and one from the 2018 PHAC review, was zero transmissions/100 person-years (95% CI: 0.00-0.10). No studies in the rapid review provided data on the risk of sexual transmission of HIV in situations of varying levels of viral load. Conclusion: This update highlights the consistency of evidence since the 2018 PHAC review. There remains no evidence of HIV transmission to sexual partners when a person living with HIV is on ART and maintains a suppressed viral load.

Translating evidence into practice with the National Advisory Committee on Sexually Transmitted and Blood-Borne Infections.

For over 30 years, the Government of Canada has developed guidelines on sexually transmitted and blood-borne infections (STBBI) with a group of subject matter experts. This expert group provided advice to the Public Health Agency of Canada (PHAC) from 2004 to 2019; transitioning to the National Advisory Committee on STBBI (NAC-STBBI) in 2019. NAC-STBBI supports PHAC's mandate to prevent and control infectious diseases by providing advice for the development of STBBI guidelines. The methodology for developing the NAC-STBBI recommendations is evolving to a more rigorous, systematic and transparent process that is consistent with current standards in guideline development. It is also informed by-and aligned with-the methods of several other major guideline developers. The methodology incorporates the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach, as appropriate, when conducting evidence reviews and developing recommendations. Recommendations will be published on the canada.ca website with the supporting NAC-STBBI Statement detailing the methodology and evidence used to develop them. This process will ensure that PHAC provides trustworthy evidence-based STBBI recommendations to primary care providers and public health professionals.