Efficacy of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate as treatment for primary or recent HIV infection

different technique and a definition of acute/recent HIV infection that is not exactly the same, their results are quite similar to ours. Remarkably, in terms of the prevalence of detection of polymorphic and accessory substitutions, they found 13.3% of patients with such substitutions, compared with 13.89% in our article. Moreover, even though they analyse resistance substitutions using population sequencing (with lower sensitivity than the massive sequencing performed in our centre), such an approach would not have modified our results since, in our series, all patients had a mutational load .90% of the viral load. Thus, our prevalence would have been the same using population sequencing. As with our cohort, the patients in the series of Fabrizio et al. are mostly MSM, infected with subtype B, and the most frequently detected integrase strand-transfer inhibitor (InSTI) substitution is 157Q. Several other European studies have noticed different levels of InSTI polymorphic and accessory substitutions in naive, recently diagnosed individuals. In Austria, 6% of recently diagnosed individuals had at least potentially low-level resistance to raltegravir or elvitegravir and 1% to dolutegravir. The rates of these polymorphisms and substitutions are lower in the UK and in Switzerland, but still present. In times of extremely effective antiretroviral regimens, even patients with multiple previous virological failures can become undetectable with relatively simple regimens. In this context, we agree with Fabrizio et al. that naive HIV individuals are increasingly being identified as the main source of resistance to antiretrovirals. This has been reported already in important European studies. We think that the next step is to identify, in our cohort and in other centres, such as that of Fabrizio et al., whether these patients—who all share the same risk factor for infection, the same strains with the same tropism and the same polymorphic and accessory substitutions—represent clusters of transmission or whether they are unrelated cases. While the prevalence may not change, the epidemiological message does.