More HIV-1 RNA detected and quantified with the Cobas 6800 system in patients on antiretroviral therapy.

BACKGROUND: Target-detected (TD) results or low-level viraemia (LLV) can be observed in HIV-1 patients on ART, which regularly raises questions. OBJECTIVES: We describe here the impact on HIV-1 RNA quantification of switching from the COBAS AmpliPrep/COBAS TaqMan (CAP/CTM) to the Cobas 6800 system (C6800), based on analyses of viraemia close to the lower limit of quantification (LLoQ). PATIENTS AND METHODS: We retrospectively selected two groups of patients: 200 individuals whose viral loads (VLs) were consistently <50 copies/mL with CAP/CTM for at least 3 years before switching to C6800 (group 1), and 35 other patients with confirmed LLV when C6800 was in use (group 2). In both groups, we compared several consecutive VL results performed before and after the change of quantification assay. Analyses were performed with McNemar's paired tests or Fisher's exact tests. RESULTS: In group 1, the frequency of TD results (below or above the LLoQ) increased significantly after the switch to C6800 for patients with <25% of results being TD for VLs performed with CAP/CTM (P < 0.0001). Significantly more patients had at least one VL ≥20 or ≥50 copies/mL with C6800, in both group 1 (37.0% versus 18.5%; P < 0.0001 and 6.5% versus 0%; P = 0.0009, respectively) and group 2 (100% versus 66%; P = 0.0015 and 97% versus 40%; P < 0.0001, respectively). CONCLUSIONS: C6800 revealed residual or low-level HIV-1 RNA that was not detected with CAP/CTM, resulting in twice as many patients being found to have a VL ≥20 copies/mL. Physicians and patients should be aware of possible differences in results between assays, and it is crucial to specify the quantitative assay used in studies.

Household transmission of SARS-CoV-2 infection in the Paris/Ile-de-France area.

This st udy aims to evaluate the prevalence of SARS-CoV-2 antibodies in locked-down family households to determine viral dynamics and immunity acquisition. COVID-19 individuals and their households in lockdown under the same roof during early spring 2020 were interviewed and tested using rapid immunochromatographic lateral flow antibodies assays (LFA) between July and September 2020. Outcomes were secondary infection rate (SIR) among contacts, household infection rate, and predictors of transmission. We enrolled 87 households including 87 COVID-19 index cases (female 78.2%; median age: 47.0 years, IQR: 42.0-51.5) and 255 contacts (males: 52.9%; median age: 19.0 years, IQR: 11.0-43.5) consisting of their children (42%) or spouses/partners (28.2%). A total of 95/255 contacts were SARS-CoV-2 antibody positive leading to a SIR of 37.3% (95% confidence interval (CI): 31.3-43.5%). Viral transmission was observed in 54 households (62%). SARS-CoV-2 infection was asymptomatic in 33/95 (34.7%) of SARS-CoV-2-positive contacts. Independent predictors of virus transmission from index to contacts were housing surface area < 60 m2 (OR: 5.6 [1.1; 28.2] and a four-member family compared to five (OR: 3.6 [1.2; 10.3]). Households represent a high-risk setting for SARS-CoV-2 transmission through close contact within the family amplified by the number of family members and the housing surface area.

Intermittent Bictegravir/Emtricitabine/Tenofovir Alafenamide Treatment Maintains High Level of Viral Suppression in Virally Suppressed People Living with HIV.

In this observational study, we aimed to evaluate whether bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) administered 5 or 4 days a week is able to maintain viral suppression in people living with HIV (PLHIV). We enrolled 85 patients who initiated intermittent B/F/TAF between 28 November 2018 and 30 July 2020: median (IQR) age 52 years (46-59), duration of virological suppression 9 years (3-13), CD4 633/mm3 (461-781). Median follow-up was 101 weeks (82-111). The virological success rate (no virological failure [VF]: confirmed plasma viral load [pVL] ≥ 50 copies/mL, or single pVL ≥ 200 copies/mL, or ≥50 copies/mL with ART change) was 100% (95%CI 95.8-100) and the strategy success rate (pVL < 50 copies/mL with no ART regimen change) was 92.9% (95%CI 85.3-97.4) at W48. Two VF occurred at W49 and W70, in 2 patients self-reporting poor compliance. No resistance mutation emerged at time of VF. Eight patients presented strategy discontinuation for adverse events. There was no significant change in the CD4 count, residual viraemia rate, neither body weight during follow-up, but a slight increase in CD4/CD8 ratio (p = 0.02). In conclusion, our findings suggest that B/F/TAF administered 5 or 4 days a week could maintain the control of HIV replication in virologically suppressed PLHIV while reducing cumulative exposition of ART.