Rusina Grozdeva

By 2022, Bulgaria’s National Reference Laboratory had confirmed 4024 HIV cases. We analyzed 132 pol gene sequences to characterize the molecular epidemiology of HIV-1 subtypes A1, A6, and A7 (2001–2022). A1 accounted for 50.0% (66/132) of cases, increasing after 2014, with peaks in 2019 and 2022. A6 comprised 48.5% (64/132), dominating from 2005 to 2014 before stabilizing. A7 was rare (1.5%, 2/132), detected in 2003 and 2011. Transmission patterns varied: A1 was linked to men who have sex with men (MSM) (62.1%), while A6 was primarily heterosexual (HET) (82.8%) with a balanced gender distribution (56.3% male, 43.8% female). Resistance mutations were identified in 29.6% of cases, with A6 showing higher rates of nucleoside reverse transcriptase inhibitor (NRTI) (20.3%) and non-nucleoside reverse transcriptase inhibitor (NNRTI) (7.8%) resistance than A1. Phylogenetic analysis revealed that 13 Bulgarian sequences (9.8%) were involved in transmission clusters, including 10 (7.6%) from sub-subtype A1 and 3 (2.3%) from sub-subtype A6, highlighting distinct genetic diversity and transmission patterns. Despite significant migration from Ukraine in 2022, A6 prevalence remained unchanged, suggesting localized transmission dynamics. These findings highlight a shifting HIV-1 sub-subtype distribution in Bulgaria and emphasize the need for targeted prevention, diagnosis, and treatment strategies tailored to the evolving molecular landscape.

Background: SARS-CoV-2 can trigger hyperinflammation, leading to severe COVID-19, presenting with pneumonia, acute respiratory distress syndrome (ARDS), and multiple organ failure. Specific biomarkers like leukocytes, CRP, NLR, AST, LDH, D-dimer, ferritin, and IL-6 are associated with disease severity. Anakinra, an IL-1 receptor antagonist, has been proposed to mitigate hyperinflammation, but its clinical efficacy remains uncertain. This study aimed to evaluate the effect of Anakinra on inflammatory biomarkers, oxygenation status, and survival outcomes in hospitalized patients with moderate to severe COVID-19 (according to the National Institute of Health severity scale), compared to standard treatment. Methods: A retrospective analysis included 65 patients (mean age 75.51 ± 9.54 years; 58.5% male, 41.5% female) hospitalized with moderate to severe COVID-19. Patients were divided into two groups: a control group receiving standard treatment (n = 24) and a target group treated with Anakinra (n = 41). Biomarkers and oxygenation status were assessed on Days 0, 3, and 7. Statistical analyses compared the groups for changes in leukocytes, NLR, CRP, AST, LDH, D-dimer, ferritin, and IL-6. Results: Anakinra treatment was associated with significant reductions in leukocytes, NLR, D-dimer, ferritin, IL-6, and CRP by Days 3 and 7. Improvements in oxygenation status were observed, although no survival benefits were noted. The control group showed no significant biomarker changes except for AST and LDH on Day 7. Conclusions: Anakinra demonstrated favorable effects on biomarkers and oxygenation in moderate to severe COVID-19 but did not improve survival. Further studies are needed to validate these findings.

A prospective clinical-epidemiological study was conducted to evaluate the dynamics of biomarkers in hospitalized patients with moderate to severe COVID-19 (according to the National Institute of Health severity scale) treated with Anakinra, compared to those receiving standard treatment. The study included 65 patients with a mean age of 75.51±9.54 years, ranging from 44 to 99 years. Among the study participants, 38 (58.5%) were male and 27 (41.5%) were female. The patients were divided into two groups: control group (standard treatment): 24 patients (36.9%) and target group (Anakinra treatment): 41 patients (63.1%). The results showed a significant relationship between the dynamics of leukocytes, ASAT, LDH, D-dimer, ferritin, and IL-6 and the administration of Anakinra. In the control group, no significant dynamics were observed in leukocyte count, D-dimer, ferritin, or IL-6. A statistically significant decrease in ASAT and LDH values in the control group was noted only on Day 7. In the Anakinra group, significantly (or with borderline statistical significance, p<0.1) lower mean values were observed for leukocytes, NLR, D-dimer, ferritin, and IL-6 on Days 3 and 7 compared to the control group. Additionally, significantly lower CRP values were detected in the Anakinra group on Day 7 compared to the control group.

The increased life expectancy of PLHIV (People Living with HIV) and the successful highly combined antiretroviral therapy (cART) poses new clinical challenges regarding aging and its co-morbid condition. It is commonly believed that HIV infection “accelerates” aging. Human immunodeficiency virus type 1 (HIV-1) infection is characterized by inflammation and immune activation that persists despite cART, and that may contribute to the development of co-morbid conditions. In this regard, we aimed to compare current cART regimens in light of premature aging to evaluate differences in their ability to reduce immune activation and inflammation in virologically suppressed patients. We studied a panel of biomarkers (IFN-γ, IL-1β, IL-12p70, IL-2, IL-4, IL-5, IL-6, IL-13, IL-18, GM-CSF, TNF-α, C-reactive protein, D-dimer, soluble CD14), which could provide a non-invasive and affordable approach to monitor HIV-related chronic inflammation. The results of the current study do not provide hard evidence favoring a particular cART regimen, although they show a less favorable regimen profile containing a protease inhibitor. Our data suggest an incomplete reduction of inflammation and immune activation in terms of the effective cART. It is likely that the interest in various biomarkers related to immune activation and inflammation as predictors of clinical outcomes among PLHIV will increase in the future.

Transmitted HIV drug resistance in Bulgaria was first reported in 2015 using data from 1988–2011. We determined the prevalence of surveillance drug resistance mutations (SDRMs) and HIV-1 genetic diversity in Bulgaria during 2012–2020 using polymerase sequences from 1053 of 2010 (52.4%) antiretroviral therapy (ART)-naive individuals. Sequences were analyzed for DRM using the WHO HIV SDRM list implemented in the calculated population resistance tool at Stanford University. Genetic diversity was inferred using automated subtyping tools and phylogenetics. Cluster detection and characterization was performed using MicrobeTrace. The overall rate of SDRMs was 5.7% (60/1053), with 2.2% having resistance to nucleoside reverse transcriptase inhibitors (NRTIs), 1.8% to non-nucleoside reverse transcriptase inhibitors (NNRTIs), 2.1% to protease inhibitors (PIs), and 0.4% with dual-class SDRMs. We found high HIV-1 diversity, with the majority being subtype B (60.4%), followed by F1 (6.9%), CRF02_AG (5.2%), A1 (3.7%), CRF12_BF (0.8%), and other subtypes and recombinant forms (23%). Most (34/60, 56.7%) of the SDRMs were present in transmission clusters of different subtypes composed mostly of male-to-male sexual contact (MMSC), including a 14-member cluster of subtype B sequences from 12 MMSC and two males reporting heterosexual contact; 13 had the L90M PI mutation and one had the T215S NRTI SDRM. We found a low SDRM prevalence amid high HIV-1 diversity among ART-naive patients in Bulgaria during 2012–2020. The majority of SDRMs were found in transmission clusters containing MMSC, indicative of onward spread of SDRM in drug-naive individuals. Our study provides valuable information on the transmission dynamics of HIV drug resistance in the context of high genetic diversity in Bulgaria, for the development of enhanced prevention strategies to end the epidemic.