aidsmap news story
The presentation of a study at CROI 2026 caused consternation when it appeared to contradict data that have served as the basis for the ‘Undetectable equals Untransmittable’ (U=U) campaign, which informs people with HIV that they cannot pass on HIV during sex if they have an ‘undetectable’ viral load – defined in the foundational studies as below 200.
The study, presented by Dr Michael Martin of Johns Hopkins University calculated that someone testing with a low but detectable viral load ranging from 200-1000 did have a quantifiable risk of passing on HIV in the next year.
In couples where one partner was HIV positive and the other negative, its model suggested that someone whose viral load was 15,000 or more at a particular timepoint had a 14% risk of passing on HIV to their partner within a year, and 2.9% if their viral load was 1000 at that timepoint.
But what really concerned audience members was that the model said that if their viral load was 200 at the time of testing, then there was still 0.6% risk of their passing on HIV to their partner in the following year.
Read the full news story here.View all aidsmap reports from CROI 2026
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