Viral genetic variation accounts for a third of variability in HIV-1 set-point viral load in Europe

HIV-1 set-point viral load—the approximately stable value of viraemia in the first years of chronic infection—is a strong predictor of clinical outcome and is highly variable across infected individuals. To better understand HIV-1 pathogenesis and the evolution of the viral population, we must quantify the heritability of set-point viral load, which is the fraction of variation in this phenotype attributable to viral genetic variation. However, current estimates of heritability vary widely, from 6% to 59%. Here we used a dataset of 2,028 seroconverters infected between 1985 and 2013 from 5 European countries (Belgium, Switzerland, France, the Netherlands and the United Kingdom) and estimated the heritability of set-point viral load at 31% (CI 15%–43%). Specifically, heritability was measured using models of character evolution describing how viral load evolves on the phylogeny of whole-genome viral sequences. In contrast to previous studies, (i) we measured viral loads using standardized assays on a sample collected in a strict time window of 6 to 24 months after infection, from which the viral genome was also sequenced; (ii) we compared 2 models of character evolution, the classical “Brownian motion” model and another model (“Ornstein–Uhlenbeck”) that includes stabilising selection on viral load; (iii) we controlled for covariates, including age and sex, which may inflate estimates of heritability; and (iv) we developed a goodness of fit test based on the correlation of viral loads in cherries of the phylogenetic tree, showing that both models of character evolution fit the data well. An overall heritability of 31% (CI 15%–43%) is consistent with other studies based on regression of viral load in donor–recipient pairs. Thus, about a third of variation in HIV-1 virulence is attributable to viral genetic variation

The HIV continuum of care in European Union countries in 2013: data and challenges

BACKGROUND: UNAIDS has set a 90-90-90 target to curb the HIV epidemic by 2020, but methods used to assess whether countries have reached this target are not standardised, hindering comparisons. METHODS: Through a collaboration formed by the European Centre for Disease Prevention and Control (ECDC) with European HIV cohorts and surveillance agencies, we constructed a standardised, four-stage continuum of HIV care for 11 European Union (EU) countries for 2013. Stages were defined as: 1) number of people living with HIV (PLHIV) in the country by end of 2013; 2) proportion of stage 1 ever diagnosed; 3) proportion of stage 2 ever initiated ART; and 4) proportion of stage 3 who became virally-suppressed (≤200 copies/mL). Case surveillance data were used primarily to derive stages 1 (using back-calculation models) and 2, and cohort data for stages 3 and 4. RESULTS: In 2013, 674,500 people in the 11 countries were estimated to be living with HIV, ranging from 5,500 to 153,400 in each country. Overall HIV prevalence was 0.22% (range 0.09%-0.36%). Overall proportions, of each previous stage, were 84% diagnosed, 84% on ART, and 85% virally-suppressed (60% of PLHIV). Two countries achieved ≥90% for all stages, and over half had reached ≥90% for at least one stage. CONCLUSIONS: EU countries are nearing the 90-90-90 target. Reducing the proportion undiagnosed remains the greatest barrier to achieving this target, suggesting further efforts are needed to improve HIV testing rates. Standardising methods to derive comparable continuums of care remains a challenge

Increasing hepatitis B vaccination coverage and decreasing hepatitis B co-infection prevalence among people with HIV-1 in Germany, 1996–2019. Results from a cohort study primarily in men who have sex with men

Objectives: Viral hepatitis co-infection among people living with HIV is known to accelerate the progression of liver disease and AIDS. An increased prevalence and incidence of hepatitis B virus (HBV) infection among people living with HIV demands continuous monitoring to adapt targeted prevention strategies to reach the global goals of eliminating viral hepatitis as a public health threat. Methods: We determined the prevalence and incidence of HBV for the years 1996–2019 from yearly blood sample testing and questionnaire reports among people living with HIV belonging to a nationwide, multicentre observational, prospective cohort study. Results: Among this study population of 3479 participants, the majority (87%) indicated that being men who have sex with men (MSM) was their likely HIV transmission route; 51% were recruited from Berlin. HBV prevalence for acute/chronic and resolved infections decreased from 4.1% and 45% in 1996–1999 to 1.3% and 16% in 2019, respectively. Simultaneously, participants with a serological status indicating HBV vaccination increased from 25% in 1996–1999 to 69% in 2019. Among vaccinated participants with relevant information (n = 1135), 38% received their first HBV vaccination after HIV infection. The HBV incidence rate in 565 eligible participants decreased from 6.9/100 person-years in 2004–2007 to 0.45/100 person-years in 2015. Conclusion: Increasing vaccination coverage because of a general HBV vaccination recommendation and catch-up vaccination efforts among risk groups decreased HBV infection prevalence over time among this study population of people living with HIV, primarily MSM and from Berlin. Despite this success, the prevalence and incidence of HBV remains higher than in the general population in Germany. This emphasizes the need for continued HBV prevention by promoting HBV vaccination and HBV screening at regular intervals based on the individual risk behaviour.Peer Reviewe

The Incidence of AIDS-Defining Illnesses at a Current CD4 Count ≥200 Cells/µL in the Post-Combination Antiretroviral Therapy Era

The incidence of AIDS was higher in patients with a current CD4 count of 500-749 cells/µL compared to 750-999 cells/µL, but did not decrease further at higher CD4 levels. Results were similar in those virologically suppressed on combination antiretroviral therapy, suggesting immune reconstitution is incomplete until CD4 >750/µ

Does rapid HIV disease progression prior to combination antiretroviral therapy hinder optimal CD4 + T-cell recovery once HIV-1 suppression is achieved?

Objective: This article compares trends in CD4+ T-cell recovery and proportions achieving optimal restoration (>=500 cells/µl) after viral suppression following combination antiretroviral therapy (cART) initiation between rapid and nonrapid progressors. Methods: We included HIV-1 seroconverters achieving viral suppression within 6 months of cART. Rapid progressors were individuals experiencing at least one CD4+ less than 200 cells/µl within 12 months of seroconverters before cART. We used piecewise linear mixed models and logistic regression for optimal restoration. Results: Of 4024 individuals, 294 (7.3%) were classified as rapid progressors. At the same CD4+ T-cell count at cART start (baseline), rapid progressors experienced faster CD4+ T-cell increases than nonrapid progressors in first month [difference (95% confidence interval) in mean increase/month (square root scale): 1.82 (1.61; 2.04)], which reversed to slightly slower increases in months 1–18 [-0.05 (-0.06; -0.03)] and no significant differences in 18–60 months [-0.003 (-0.01; 0.01)]. Percentage achieving optimal restoration was significantly lower for rapid progressors than nonrapid progressors at months 12 (29.2 vs. 62.5%) and 36 (47.1 vs. 72.4%) but not at month 60 (70.4 vs. 71.8%). These differences disappeared after adjusting for baseline CD4+ T-cell count: odds ratio (95% confidence interval) 0.86 (0.61; 1.20), 0.90 (0.38; 2.17) and 1.56 (0.55; 4.46) at months 12, 36 and 60, respectively. Conclusion: Among people on suppressive antiretroviral therapy, rapid progressors experience faster initial increases of CD4+ T-cell counts than nonrapid progressors, but are less likely to achieve optimal restoration during the first 36 months after cART, mainly because of lower CD4+ T-cell counts at cART initiation

Calculation of Direct Antiretroviral Treatment Costs and Potential Cost Savings by Using Generics in the German HIV ClinSurv Cohort

BACKGROUND/AIM OF THE STUDY: The study aimed to determine the cost impacts of antiretroviral drugs by analysing a long-term follow-up of direct costs for combined antiretroviral therapy, cART, -regimens in the nationwide long-term observational multi-centre German HIV ClinSurv Cohort. The second aim was to develop potential cost saving strategies by modelling different treatment scenarios. Antiretroviral regimens (ART) from 10,190 HIV-infected patients from 11 participating ClinSurv study centres have been investigated since 1996. Biannual data cART-initiation, cART-changes, surrogate markers, clinical events and the Centre of Disease Control- (CDC)-stage of HIV disease are reported. Treatment duration was calculated on a daily basis via the documented dates for the beginning and end of each antiretroviral drug treatment. Prices were calculated for each individual regimen based on actual office sales prices of the branded pharmaceuticals distributed by the license holder including German taxes. During the 13-year follow-up period, 21,387,427 treatment days were covered. Cumulative direct costs for antiretroviral drugs of €812,877,356 were determined according to an average of €42.08 per day (€7.52 to € 217.70). Since cART is widely used in Germany, the costs for an entire regimen increased by 13.5%. Regimens are more expensive in the advanced stages of HIV disease. The potential for cost savings was calculated using non-nucleotide-reverse-transcriptase-inhibitor, NNRTI, more frequently instead of ritonavir-boosted protease inhibitor, PI/r, in first line therapy. This calculation revealed cumulative savings of 10.9% to 19.8% of daily treatment costs (50% and 90% substitution of PI/r, respectively). Substituting certain branded drugs by generic drugs showed potential cost savings of between 1.6% and 31.8%. Analysis of the data of this nationwide study reflects disease-specific health services research and will give insights into the cost impacts of antiretroviral therapy, and might allow a more rational allocation of resources within the German health care system

Effect of incident hepatitis C infection on CD4+ cell count and HIV RNA trajectories based on a multinational HIV seroconversion cohort

Background: Most studies on hepatitis C virus (HCV)/HIV-coinfection do not account for the order and duration of these two infections. We aimed to assess the effect of incident HCV infection, and its timing relative to HIV seroconversion (HIVsc) in HIV-positive MSM on their subsequent CD4+ T-cell count and HIV RNA viral load trajectories. Methods: We included MSM with well estimated dates of HIVsc from 17 cohorts within the CASCADE Collaboration. HCV-coinfected MSM were matched to as many HIV monoinfected MSM as possible by HIV-infection duration and combination antiretroviral therapy (cART) use. We used multilevel random-effects models stratified by cART use to assess differences in CD4+ cell count and HIV RNA viral load trajectories by HCV-coinfection status. Findings: We matched 214 (ART-naive) and 147 (on cART) HCV-coinfected MSM to 5384 and 3954, respectively, matched controls. The timing of HCV seroconversion (HCVsc) relative to HIVsc had no demonstrable effect on HIV RNA viral load or CD4+ cell count trajectories. In the first 2–3 years following HCVsc CD4+ cell counts were lower among HCV-coinfected MSM, but became comparable with HIV monoinfected MSM thereafter. In ART-naive MSM, during the first 2 years after HCVsc, HIV RNA viral load levels were lower or comparable with HIV monoinfected, tending to be higher thereafter. In MSM on cART, HCV had no significant effect on having a detectable HIV RNA viral load. Interpretation: Irrespective of the duration of HIV infection when HCV is acquired, CD4+ cell counts were temporarily lower following HCVsc, even when on cART. The clinical implications of our findings remain to be further elucidated

Phylogenetic estimation of the viral fitness landscape of HIV-1 set-point viral load.

Set-point viral load (SPVL), a common measure of human immunodeficiency virus (HIV)-1 virulence, is partially determined by viral genotype. Epidemiological evidence suggests that this viral property has been under stabilising selection, with a typical optimum for the virus between 10 <sup>4</sup> and 10 <sup>5</sup> copies of viral RNA per ml. Here we aimed to detect transmission fitness differences between viruses from individuals with different SPVLs directly from phylogenetic trees inferred from whole-genome sequences. We used the local branching index (LBI) as a proxy for transmission fitness. We found that LBI is more sensitive to differences in infectiousness than to differences in the duration of the infectious state. By analysing subtype-B samples from the Bridging the Evolution and Epidemiology of HIV in Europe project, we inferred a significant positive relationship between SPVL and LBI up to approximately 10 <sup>5</sup> copies/ml, with some evidence for a peak around this value of SPVL. This is evidence of selection against low values of SPVL in HIV-1 subtype-B strains, likely related to lower infectiousness, and perhaps a peak in the transmission fitness in the expected range of SPVL. The less prominent signatures of selection against higher SPVL could be explained by an inherent limit of the method or the deployment of antiretroviral therapy