Search Results (217)

The identification of recent HIV infections among newly diagnosed HIV cases is relevant to both implementing targeted prevention measures and estimating HIV incidence. We analyzed data on new HIV diagnoses in Italy from 2012 to 2023. We selected cases that were tested by at least one of three criteria (test for HIV recency, data on HIV seroconversion, clinical signs of acute HIV infection) to assess the rate of recent (<1 year) HIV infections. We analyzed these cases by gender, age group, nationality, and mode of transmission, and revaluated cases that were initially scored as a late diagnosis but then classified as a recent infection. Out of 36,289 new HIV diagnoses, 17,558 (48.8%) were tested for recent infection by at least one criterion and 3772 (21.5%) were classified as recent. At multivariate analysis, the probability of being recently infected was significantly higher among males, people aged 15–44 years, Italians, individuals diagnosed in Northern and Central Italy, heterosexual males, MSM, and people with a CD4 count ≥ 350 cells/uL at diagnosis. Of 8658 cases initially classified as late diagnoses, 979 (11.3%) were reclassified as recent by the aforementioned criteria. Monitoring recent infections among new HIV diagnoses is beneficial to individuals—because it motivates recently infected people to comply with antiretroviral treatment (which is more effective if started early) and to collaborate to partner notification, and to public health, as it provides evidence of epidemiological changes and stresses the need for targeted prevention in well-defined populations at risk. Full article

Background: Right ventricular (RV) dysfunction is associated with poor clinical outcomes in critically ill sepsis patients, but its pathophysiology and predictors are incompletely characterized. We aimed to investigate the predictors of RV dysfunction and its outcomes in sepsis patients admitted to the intensive care unit (ICU). Methods: This is a single-center retrospective cohort study of adult patients admitted to the ICU for sepsis who had echocardiography within 72 h of diagnosis. Patients with acute coronary syndrome, acute decompensated heart failure, or significant valvular dysfunction were excluded. RV dysfunction was defined as the presence of RV dilation, hypokinesis, or both. Demographics and clinical outcomes were obtained from electronic medical records. Results: A total of 361 patients were included in our study—47 with and 314 without RV dysfunction. The mean age of the population was 66.8 years and 54.6% were females. Compared to those without RV dysfunction, patients with RV dysfunction were more likely to require mechanical ventilation (63.8% vs. 43.9%, p = 0.01) and vasopressor support (61.7% vs. 36.6%, p < 0.01). On multivariate logistic regression analysis, increasing age (OR 1.03, 95% C.I. 1.00–1.06), a history of HIV infection (OR 5.88, 95% C.I. 1.57–22.11) and atrial fibrillation (OR 4.34, 95% C.I. 1.83–10.29), and presence of LV systolic dysfunction (OR 14.40, 95% C.I. 5.63–36.84) were independently associated with RV dysfunction. Patients with RV dysfunction had significantly worse 30-day survival (Log-Rank p = 0.023). On multivariate Cox regression analysis, older age (HR 1.02, 95% C.I. 1.00–1.04) and peak lactate (HR 1.16, 95% C.I. 1.11–1.21) were independent predictors of 30-day mortality. Conclusions: Among other findings, our data suggests a possible association between a history of HIV infection and RV dysfunction in critically ill sepsis patients, and this should be investigated further in future studies. Patients with evidence of RV dysfunction had poorer survival in this population; however this was not an independent predictor of mortality in the multivariate analysis. A larger cohort with a longer follow-up period may provide further insights. Full article

Artificial intelligence (AI) techniques—ranging from hybrid mechanistic–machine learning (ML) ensembles to gradient-boosted decision trees, support-vector machines, and deep neural networks—are transforming the management of seasonal influenza, respiratory syncytial virus (RSV), human immunodeficiency virus (HIV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Symptom-based triage models using eXtreme Gradient Boosting (XGBoost) and Random Forests, as well as imaging classifiers built on convolutional neural networks (CNNs), have improved diagnostic accuracy across respiratory infections. Transformer-based architectures and social media surveillance pipelines have enabled real-time monitoring of COVID-19. In HIV research, support-vector machines (SVMs), logistic regression, and deep neural network (DNN) frameworks advance viral-protein classification and drug-resistance mapping, accelerating antiviral and vaccine discovery. Despite these successes, persistent challenges remain—data heterogeneity, limited model interpretability, hallucinations in large language models (LLMs), and infrastructure gaps in low-resource settings. We recommend standardized open-access data pipelines and integration of explainable-AI methodologies to ensure safe, equitable deployment of AI-driven interventions in future viral-outbreak responses. Full article

The main challenge after engraftment of human tissues to mice is the development of graft-versus-host disease. It often occurs in an acute form, which reduces the time frame for observations. This is especially important to take into account when planning long-term studies of chronic diseases such as HIV infection. In addition, in mice, even with a similar genotype but different origin, the interaction between the graft and the recipient’s organism can manifest itself differently. We engrafted human immune cells in three different concentrations into immunodeficient NOD/Shi-Prkdc^scid Il2rg^em1/Cyagen mice. Then, the initial points of development of a severe graft-versus-host reaction and the maximum possible time window for humane observation were determined. The study included regular complete blood count and the monitoring of the dynamics of the concentration of human cells in the blood of mice. In addition, the effect of grafts on the activation of the recipient’s immune system was assessed. Finally, necropsy and histological and immunohistochemical examinations of the organs were performed to determine the localization of human cells. In this way, critical factors determining the success of human immune system reconstitution in mice were identified. Full article

While viral pathogens are often subdivided into neurotropic and non-neurotropic categories, systemic inflammation caused by non-neurotropic viruses still possesses the ability to alter the central nervous system (CNS). Studies of CNS disease induced by viral infection, whether neurotropic or not, are presented with a unique set of challenges. First, because brain biopsies are rarely necessary to diagnose viral-associated neurological disorders, antemortem tissue samples are not readily available for study and human pathological studies must rely on end-stage, postmortem evaluations. Second, in vitro models fail to fully capture the nuances of an intact immune system, necessitating the use of animal models to fully characterize pathogenesis and identify potential therapeutic approaches. Non-human primates (NHP) represent a particularly attractive animal model in that they overcome many of the limits posed by more distant species and most closely mirror human disease pathogenesis and susceptibility. Here, we review NHP infection models of viruses known to infect and/or replicate within cells of the CNS, including West Nile virus, the equine encephalitis viruses, Zika virus, and herpesviruses, as well as those known to alter the immune status of the brain in the absence of significant CNS penetrance, including human immunodeficiency virus (HIV) in the current era of combination antiretroviral therapy (cART) and the coronavirus of severe acute respiratory syndrome (SARS)-CoV−2. This review focuses on viruses with an established role in causing CNS disease, including encephalitis, meningitis, and myelitis and NHP models of viral infection that are directly translatable to the human condition through relevant routes of infection, comparable disease pathogenesis, and responses to therapeutic intervention. Full article

Background/Objective: Pulmonary fungal infections are a significant diagnostic challenge, primarily affecting immunocompromised individuals, such as those with HIV, cancer, or organ transplants, and they often lead to substantial morbidity and mortality if untreated. These infections trigger acute inflammatory and immune responses, which may progress to chronic inflammation. This process involves myofibroblast recruitment, the deposition of extracellular matrix, and vascular remodeling, ultimately contributing to pulmonary hypertension. Despite its clinical relevance, pulmonary hypertension secondary to fungal infections remains under-recognized in practice and poorly studied in research. Results/Conclusion: This narrative mini-review explores three key mechanisms underlying vascular remodeling in this context: (1) endothelial injury caused by fungal emboli or autoimmune reactions, (2) direct vascular remodeling during chronic infection driven by inflammation and fibrosis, and (3) distant vascular remodeling post-infection, as seen in granulomatous diseases like paracoccidioidomycosis. Further research and clinical screening for pulmonary hypertension in fungal infections are crucial to improving patient outcomes. Full article

Background: Vaccines represent one of the most affordable and efficient tools for controlling infectious diseases; however, the development of efficacious vaccines against complex pathogens remains a major challenge. Adjuvants play a relevant role in enhancing vaccine-induced immune responses. One such molecule is interferon-stimulated gene 15 (ISG15), a key modulator of antiviral immunity that acts both through ISGylation-dependent mechanisms and as a cytokine-like molecule. Methods: In this study, we assessed the immunostimulatory potential of ISG15 as an adjuvant in Modified Vaccinia virus Ankara (MVA)-based vaccine candidates targeting Zika virus (ZIKV) and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Early innate responses and immune cell infiltration were analyzed in immunized mice by flow cytometry and cytokine profiling. To elucidate the underlying mechanism of action of ISG15, in vitro co-infection studies were performed in macrophages. Finally, we evaluated the magnitude and functional quality of the elicited antigen-specific cellular immune responses in vivo. Results: Analysis of early innate responses revealed both platform- and variant-specific effects. ISG15AA preferentially promoted natural killer (NK) cell recruitment at the injection site, whereas ISG15GG enhanced myeloid cell infiltration in draining lymph nodes (DLNs), particularly when delivered via MVA. Moreover, in vitro co-infection of macrophages with MVA-based vaccine vectors and the ISG15AA mutant led to a marked increase in proinflammatory cytokine production, highlighting a dominant role for the extracellular, ISGylation-independent functions of ISG15 in shaping vaccine-induced immunity. Notably, co-infection of ISG15 with MVA-ZIKV and MVA-SARS-CoV-2 vaccine candidates enhanced the magnitude of antigen-specific immune responses in both vaccine models. Conclusions: ISG15, particularly in its ISGylation-deficient form, acts as a promising immunomodulatory adjuvant for viral vaccines, enhancing both innate and adaptive immune responses. Consistent with previous findings in the context of Human Immunodeficiency virus type 1 (HIV-1) vaccines, this study further supports the potential of ISG15 as an effective adjuvant for vaccines targeting viral infections such as ZIKV and SARS-CoV-2. Full article

Human cytomegalovirus (HCMV) coinfection is associated with a faster HIV disease progression and adverse clinical outcomes. HCMV-encoded miRNA expression, in individuals acutely infected with HIV (AHI), compared to those with HCMV monoinfection, was investigated in relation to viral replication and inflammation/immune activation. Sixteen individuals with AHI coinfected with HCMV were analyzed at serodiagnosis (T0) and after 6 (T1) and 12 (T2) months of antiretroviral therapy initiated within one week from serodiagnosis. Fourteen HCMV monoinfected subjects were also studied. Plasma RNA was reverse-transcribed and amplified with a panel designed to detect 14 different HCMV-microRNAs (miRNAs). VEGF-A and IP-10 plasma levels were quantified using ELISA. Except for hcmv-miR-70-3p, detected in all subjects, hcmv-miR-UL112-3p, hcmv-miR-US25-1-5p, hcmv-miR-US25-2-3p, hcmv-miR-US4-5p, hcmv-miR-US5-1, hcmv-miR-US5-2-3p, hcmv-miR-UL36-3p, and hcmv-miR-UL36-5p were significantly more frequently detected when HCMV DNA was present (lytic infection). In latent HCMV infection, hcmv-miR-UL22A-5p and hcmv-miR-UL148D were more frequently observed in HIV/HCMV-coinfected individuals, compared to mono-HCMV infection. Hcmv-miR-UL22A-5p and hcmv-miR-US33-5p showed a direct correlation with HIV-1 RNA. Notable positive correlations between hcmv-miR-UL22A-5p and the interferon-gamma-inducible protein 10 (IP-10), as well as between hcmv-miR-UL148D and the vascular endothelial growth factor A (VEGF-A), were also observed. HCMV-miRNA expression varies between lytic and latent infection and differs in HIV coinfection. In HCMV/HIV coinfection, increased levels of hcmv-miR-UL148D, associated with VEGF-A production, seem to be less linked to HIV viremia with respect to hcmv-miR-UL22A-5p and hcmv-miR-US33-5p. A deeper understanding of HCMV-encoded miRNA biology may facilitate the comprehension of HCMV/HIV coinfection pathogenetic mechanisms. Full article

Inflammation is a crucial component of the immune response essential for host defense and tissue repair. However, when the immune response becomes dysregulated, it can contribute to the pathogenesis of chronic diseases. While acute inflammation is a short-lived, protective response, chronic inflammation is sustained over time and can lead to immune dysfunction, tissue damage, and disease progression. The chronic inflammation theory of disease suggests that persistent immune activation/inflammation underlies both infectious and non-infectious conditions and serves as a unifying mechanism across distinct pathological states. In this review article, we argue that human immunodeficiency virus (HIV) infection represents a prime model for studying chronic inflammation, and that despite effective viral suppression with antiretroviral therapy (ART), people living with HIV (PLWH) exhibit persistent immune activation, systemic inflammation, and an increased risk of cardiovascular, metabolic, and neurodegenerative diseases. Here, the interplay between microbial translocation, immune dysregulation, and metabolic reprogramming fuels a state of chronic inflammation that accelerates disease progression beyond HIV itself. Key factors such as T-cell exhaustion, persistent monocyte/macrophage activation, and immunometabolic dysfunction contribute to such a sustained inflammatory state. This review explores the molecular and cellular mechanisms driving chronic inflammation in HIV infection with a focus on immunometabolism and its implications for broader inflammatory diseases. By understanding such pathways, we can identify novel therapeutic targets to mitigate inflammation-driven disease progression not only in HIV but across a spectrum of chronic inflammatory conditions. Full article

Type I interferons (IFN-Is) play a dual role in the immune response to HIV-1, providing early antiviral defense while driving immune dysfunction in the chronic phase. During acute infection, robust IFN signaling is critical in controlling viral replication, activating innate immunity, and limiting reservoir establishment. However, sustained IFN-I activation during chronic infection fuels systemic inflammation, immune exhaustion, and fibrosis, particularly in lymphoid tissues such as gut-associated lymphoid tissue (GALT). Prolonged IFN-I exposure upregulates inhibitory receptors on T cells, impairs metabolic fitness, and fosters an immunosuppressive cytokine milieu that weakens overall immune responses. In contrast to natural SIV (Simian immunodeficiency virus) hosts, IFN-I responses are tightly regulated to prevent chronic immune activation and tissue damage. However, humans and non-natural hosts experience persistent Interferon Stimulated Gene (ISG) expression and IFN-I driven inflammation. Emerging therapeutic strategies seek to harness the antiviral benefits of IFN-I while mitigating its pathogenic effects. Approaches such as the IFNAR blockade, autophagy induction, JAK-STAT inhibition, and combined immune inhibitory blockade therapy show promise in restoring immune balance and enhancing T cell function. This review examines the mechanisms of IFN-I dysregulation in chronic HIV-1 infection and highlights novel interventions aimed at finetuning IFN-I signaling for therapeutic benefit. Full article

Microglia are the primary target and reservoir of HIV infection in the central nervous system (CNS), which contributes to HIV-associated neurocognitive disorder (HAND). However, studying HIV infection of microglia has been challenged by the limited availability of primary human microglial cells. To overcome this issue, investigators have developed various microglial models for HIV studies, including immortalized human microglial cell lines, HIV latently infected microglial clones, peripheral blood monocyte-derived microglia (MMG), induced pluripotent stem cell (iPSC)-derived microglia (iMg), and microglia-containing cerebral organoids (MCOs) from iPSCs. Though these models have been used in many laboratories, the published data about their expression of the specific human microglia markers and the HIV entry receptors are conflicting. In addition, there is limited information about their feasibility and applicability as a suitable model for acute and/or latent HIV infection. This review provides a concise summary of the currently used human microglial models, with a focus on their suitability for NeuroHIV research. Full article

Background: The MeMed BV^® BV score is a novel, promising host-protein score, differentiating bacterial from viral infections, that combines the expression levels of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), interferon gamma-induced protein-10 (IP-10), and C-reactive protein (CRP). The aim of our study was to determine its diagnostic accuracy in hospitalized febrile children. Methods: A prospective study was performed from December 2023 to April 2024 in two pediatric clinics at “Aghia Sophia” Children’s Hospital, Athens, Greece. Patients > 3 months old, presenting with fever, clinical suspicion of acute infection, and symptoms onset up to 7 days prior were considered eligible. Patients with cancer, Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), Tuberculosis (TB), and immunodeficiency were excluded. Two pediatricians reviewed the clinical, laboratory, microbiological, and radiological data and assigned the final diagnosis. The experts were blinded to the BV scores. Results: One hundred and thirty-five patients were enrolled. The predominant medical condition was respiratory tract infection (59.3% lower, 26.7% upper). Twenty-nine (21.5%) patients were diagnosed with bacterial infections. The BV score demonstrated a sensitivity of 96.2%, specificity of 88.7%, and negative predictive value (NPV) of 98.9% for bacterial infections. Equivocal BV scores were reported in 8.9% of cases and were excluded from calculations. The area under the curve was 0.96 (95% CI: 0.93–0.99). A ROC curve analysis was performed, and the optimal cut-off score was estimated at 60, providing a sensitivity of 93.1%, specificity of 88.7%, and NPV of 97.9%. Conclusions: In our study population, the BV score showed high sensitivity and NPV in bacterial infection diagnosis. Further studies are needed to assess the possibility of replacing the “equivocal” range with a narrower one or a specific cut-off value. Full article

Acute HIV-1 infection (AHI) is a transient period where the virus causes evident damage to the immune system, including an extensive apoptosis of CD4+ T cells associated with a high level of activation and a major cytokine storm to fight the invading virus. HIV infection establishes persistence by integrating the viral genome into host cell DNA in both replicating and non-replicating forms, effectively hiding from immune surveillance within infected lymphocytes as cellular reservoirs. The measurement of total HIV-1 DNA in peripheral blood mononuclear cells (PBMCs) is a reliable reflection of this reservoir. Initiating treatments during AHI with nucleoside reverse transcriptase inhibitors (NRTIs) and/or integrase strand transfer inhibitors (INSTIs) is essential to alter the dynamics of the global reservoir expansion, and to reduce the establishment of long-lived cellular and tissue reservoirs, while preserving and enhancing specific and non-specific immune responses. Furthermore, some of the patients treated at the AHI stage may become post-treatment controllers and should be informative regarding the mechanism of viral control, so patients treated during AHI are undoubtedly the best candidates to test innovative remission strategies toward a functional cure that could play a pivotal role in long-term HIV control. AHI is characterized by high levels of viral replication, with a significant increase in the risk of HIV transmission. Detecting AHI and initiating early treatment following diagnosis provides a window of opportunity to control the epidemic, particularly in high-risk populations. Full article

Background/Objectives: Before the Coronavirus disease 2019 (COVID-19) era, the global prevalence of pulmonary arterial hypertension (PAH) was between 0.4 and 1.4 per 100,000 people. The long-term effects of protracted COVID-19 associated with pulmonary vascular disease (PVD) risk factors may increase this prevalence. According to preliminary data, the exact prevalence of early estimates places the prevalence of PVD in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection at 22%, although its predictive value remains unknown. PVD caused by COVID-19 co-infections is understudied and underreported, and its future impact is unclear. However, due to COVID-19/co-infection pathophysiological effects on pulmonary vascularization, PVD mortality and morbidity may impose a genuine concern—both now and in the near future. Based on reported studies, this literature review focused on the potential link between COVID-19, parasitic co-infection, and PVD. This review article also highlights hypothetical pathophysiological mechanisms between COVID-19 and parasitic co-infection that could trigger PVD. Methods: We conducted a systematic literature review (SLR) searching peer-reviewed articles, including link between COVID-19, parasitic co-infection, and PVD. Results: This review hypothesized that multiple pathways associated with pathogens such as underlying schistosomiasis, human immunodeficiency virus (HIV), pulmonary tuberculosis (PTB), pulmonary aspergillosis, Wuchereria bancrofti, Clonorchis sinensis, paracoccidioidomycosis, human herpesvirus 8, and scrub typhus coupled with acute or long COVID-19, may increase the burden of PVD and worsen its mortality in the future. Conclusions: Further experimental studies are also needed to determine pathophysiological pathways between PVD and a history of COVID-19/co-infections. Full article

Parvovirus B19 (B19V) infection can affect individuals of all ages, both immunocompetent and immunocompromised. This infection is typically acute and self-limiting, most commonly resulting in rash diseases and acute febrile illness. However, its involvement in atypical manifestations such as chronic kidney disease and acute liver failure have also been reported. Diagnosis of B19V is rarely conducted in these populations, and available studies on its prevalence are limited, outdated, and do not accurately depict the current situation. This study describes and discusses retrospective investigations into the role of B19V in cases of rash diseases, acute febrile illness, anemia, occurring in the context of chronic kidney disease and HIV coinfection, and acute liver failure when no identifiable etiological agent was found, focusing on various populations in Brazil. This overview underscores the importance of recognizing the potential for severe B19V infection in all individuals, regardless of perceived immune status, as well as of considering the possibility of B19V concurrent infection, in both high-risk groups and healthy individuals to reduce the risk of serious complications and improve patient outcomes, by considering the inclusion of B19V in the routine of diagnosis and implementing management strategies. This study was limited by the absence of national surveillance data of B19V in Brazil and by the analyses that occurred retrospectively. Full article