Vertical transmission of PRRSV2 strain NVSL 97-7895 occurs during mid-gestation.

A high prevalence of hepatitis B virus strains sharing a single S gene variant in Pakistan.

Serological profile of Toxoplasma gondii in HIV/AIDS patients and its association with disease progression.

Although LIV and TBEV are closely related tick-borne flaviviruses, the outcome of an infection in sheep is considerably different. Here, we show that the effectiveness of the innate immune response to limit virus replication corresponds to a specific clinical outcome. TBEV infection seemed to be efficiently controlled at the level of the prescapular lymph node by a moderate interferon-related cytokine response. This early control prevented likely further TBEV spread and entry in the CNS. In contrast, LIV was capable of replicating to high viral loads in prescapular lymph nodes, tonsils, and brain tissues despite the strong innate immune responses induced in these tissues, which probably contributed to the observed clinical signs. This further suggests that LIV has adapted to better circumvent innate immune responses than TBEV and that the clinical manifestations can be attributed to a dysregulated response.

Epidemiological and Genomic Surveillance of Influenza virus A, RSV B and SARS-CoV-2 in Bangladesh (2022-2024).

Mycobacterium colombiense is a seldom reported non-tuberculous mycobacteria causing infections mostly in immunosuppressed patients. Thus, we present the findings of three M. colombiense isolation cases from a third-level hospital in Monterrey, Mexico, during 2020-2024. Mycobacterial identification was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Anyplex™ MTB/NTM Real-time Detection. Patients were people living with Human Immunodeficiency Virus (PLHIV), with pneumonia and lymphadenopathy. Patients had high HIV viral loads and low CD4 counts (21-103 cells/mm3). None of the cases had specific Mycobacterium avium complex (MAC) treatment, and all of them showed clinical improvement. Current non-tuberculous mycobacteria discrimination tests may not effectively diagnose significant pathogens like M. colombiense, potentially leading to delays in treatment and negatively impacting patient outcomes.

Evaluating CMV Risk Stratification, Donor Characteristics, and Post-Transplant Outcomes in Kidney Transplant Recipients: A Retrospective Eurotransplant Center Analysis.

This study examined the association between high risk human papillomavirus viral load and cervical squamous lesions using the Cobas 4800 assay and evaluated its potential as an indicator for identifying CIN2+, and analyzed the impact of multiple infections on viral load and disease risk. A total of 3,838 women who underwent hr-HPV testing were included. The Cobas 4800 assay provided cycle threshold values, which were used as indirect measures of viral load. These values were correlated with histopathological diagnoses obtained within three months of HPV testing. Among all participants, 1,660 had normal histology, 900 had CIN1, 1,019 had CIN2/3, and 259 had SCC. HPV16 Ct values decreased with increasing lesion severity in both single and multiple infections, whereas HPV18 and the 12 other hr-HPV types showed no clear correlation with lesion grade. Multiple HPV infections involving HPV16 were not associated with an increased risk of CIN2 + compared with HPV16 single infection. For both HPV16 and HPV18, Ct values did not differ significantly across CIN1, CIN2/3, and SCC between single and multiple infections. ROC curve analysis of HPV16 single infections identified a Ct threshold of 32.25 for identifying CIN2+, with an area under the curve (AUC) of 0.72, a sensitivity of 80.7%, and a specificity of 54.4%. HPV16 viral load is correlated with cervical squamous lesions, irrespective of single or multiple infections. HPV16 viral load may serve as a biomarker for indicating cervical squamous lesion occurrence. In this study, no positive association was observed between co-infection and high-grade lesions, and viral loads did not differ significantly between single and multiple infection groups. Integrating viral load assessment into clinical evaluation could thus enable more individualized risk stratification and patient management. Not applicable.

Ebola Virus Disease (EVD) increases the risk for complications to a healthy pregnancy and delivery, notably post-partum hemorrhage. Additionally, successful management of post-partum hemorrhage and resource-intensive clinical interventions are difficult in the low-resourced setting of an Ebola Treatment Unit (ETU). This report describes the clinical course of a pregnant adolescent, gravida 2 para 1, with a history of delivery by cesarean section only 12 months before her second pregnancy. She was vaccinated with rVSV-ZEBOV following the death of a family member with confirmed EVD. She was admitted to the ETU 8 days after her vaccination, where a diagnosis of EVD in pregnancy was made, and her RT-PCR results on the blood sample showed a high viral load. At admission, she was 32 weeks pregnant. She was treated with mAb114, a neutralizing monoclonal antibody. In the first two days of her treatment, viral loads were measured, and they progressively declined after the third day of treatment. On day 3 of admission, following the failure of tocolysis, she delivered a preterm live infant. Her delivery was complicated by post-partum hemorrhage, two lateral cervical and vaginal mucosa lesions, with leakage of urine through the vagina, suggesting a genito-urinary fistula due to the extension of these lesions. A manual uterine exploration was required to remove placental debris with the administration of uterotonic drugs. Methylene blue instillation confirmed the vesicovaginal fistula. Due to a lack of obstetrical equipment in the ETU, the full extent of the cervical lesions could not be assessed nor repaired. Despite our resuscitation measures and mechanical cervical compression, she died 14h after delivery of hemorrhagic shock complicated by coagulopathy with severe acute respiratory distress in the setting of acute EVD infection despite decreasing viral load. In cases of Ebola in pregnancy, not all maternal deaths due to post-partum hemorrhage are necessarily due to EVD and, therefore, could be averted with resources to provide specialized obstetric and post-partum care.

Zika virus (ZIKV) infections have been linked to severe neurological disorders, including microcephaly and Guillain-Barré syndrome in humans as well as mouse models of ZIKV infection. Despite the association, the mechanisms underlying ZIKV-induced neuropathology remain incompletely understood. We have recently shown that antigen independent CD8+ T cells mediate neurological disease in ZIKV-infected mice independent of the amount of infectious virus in the CNS. To further investigate the role of brain viral load and lymphocytes in ZIKV infection we studied the viral kinetics, pathology, and immune responses of ZIKV-infected NOD-Rag1-/-Il2rg-/- mice, which are deficient in lymphoid cells. Despite prolonged high viral titers in the brain, NOD-Rag1-/-IL2rg-/- mice did not develop neurological symptoms following ZIKV infection, contrasting with the infection outcomes of Ifnar1-/- mice which exhibit paralysis despite lower viral load. Notably, we observed significant differences in brain myeloid cells in the presence or absence of lymphoid cells. While Ifnar1-/- mice showed robust infiltration of CD45hiCD11b+ cells in the brain, lymphocyte-deficient NOD-Rag1-/-IL2rg-/- mice exhibited reduced recruitment and activation of these cells. Additionally, we found that CD45hiCD11b+ cells displayed a more inflammatory phenotype in Ifnar1-/- mice compared to NOD-Rag1-/-IL2rg-/- mice. Our study highlights the complex interplay between the immune system and viral infection in ZIKV-induced neuropathology and underscores the importance of considering immune responses in the development of therapeutic interventions for ZIKV.

ABSTRACTIn Ontario, Canada, public health authorities can issue and enforce orders to people living with HIV (PLWH). However, how public health practitioners determine when someone's behaviours constitute ‘significant’ risk remains underexplored. We drew on assemblage theory to examine how HIV risk is co‐constituted through the interplay among biomedical technologies, institutional practices, legal frameworks and social discourses. We conducted 18 semi‐structured interviews with public health personnel and used reflexive thematic analysis. Five interrelated themes emerged. First, high viral load was considered a potential risk indicator when associated with high‐risk activities. Second, discontinuity in HIV care may flag individuals for intervention. Third, co‐infection with sexually transmissible and blood‐borne infections (STBBI) triggered a viral load review to assess HIV exposure potential. Fourth, noncompliance with public health directives positioned PLWH as needing management. Fifth, Undetectable = Untransmittable (U = U) discourses have reconfigured and neutralised risk, functioning as a technology of reflexive governance. However, uptake of U = U was described as uneven across Ontario's public health units, leading to variable, and sometimes coercive, approaches. By conceptualising HIV risk as emergent, this study challenges individualised notions of responsibility and highlights the relational production of risk. Adoption of U = U and equity‐based public health practices is needed to ensure nonpunitive HIV responses.

Dolutegravir (DTG) plus lamivudine (3TC) is one of the preferred treatment regimens for HIV, yet evidence remains limited for people living with HIV (PLWH) with high baseline viral load. This study aims to evaluate the effectiveness of DTG/3TC in treatment-naive PLWH with baseline viral load > 500,000copies/mL in China. In this real-world multicenter cohort study, PLWH with baseline viral load (VL) > 500,000copies/mL who initiated DTG/3TC were recruited across 18 clinical sites in China. Matched participants from the same sites with lower baseline VL were also included as a control group. Participants were followed for 48weeks. The primary endpoint was virological suppression (HIV-1 RNA < 50copies/mL) at week48 using the US Food and Drug Administration snapshot algorithm. Of the 375 PLWH enrolled, 150 were classified into the high VL group and 225 into the low VL group. Baseline median HIV-1 RNA was 5.99 and 5.07log10copies/mL, respectively. At week48, virologic suppression was achieved in 88.0% (95%CI 82.8-93.2%) of the high VL group and 92.0% (95%CI 87.9-96.2%) of the low VL group (P = 0.233); 7.5% and 4.0% of participants in the high and low VL groups had plasma HIV-1 RNA ≥ 50copies/mL, respectively. Median CD4 increases from baseline to week48 were 153.5 and 147.0cells/μL in the high and low VL groups, respectively (P = 0.408). Safety profiles were comparable, with one grade3 adverse event in each group. DTG/3TC showed favorable virological and safety outcomes in treatment-naive PLWH with baseline HIV-1 RNA > 500,000copies/mL, suggesting that it may be a viable option for PLWH with high baseline viral load. Chinese Clinical Trial Registry: ChiCTR2300074854.

PurposeThe goal of antiretroviral therapy is to achieve and sustain the suppression of human immunodeficiency virus (HIV) viral load. In this study, we aimed to identify risk factors for low-level viremia (LLV) and examine their association with clinical outcomes in South Korea.MethodsWe retrospectively reviewed the medical records of patients with human immunodeficiency virus infection registered at Seoul Medical Center and Hallym University Sacred Heart Hospital between 2014 and 2023. LLV was defined as at least two consecutive HIV RNA measurements of 40–199 copies/mL taken more than 4 weeks apart. Patients with LLV were compared with those who maintained virological suppression (viral load < 40 copies/mL).ResultsOf the 381 patients included in the analysis, 15 (3.94%) experienced LLV. Compared with patients who maintained virological suppression, patients with LLV more frequently had an initial viral load ≥ 500,000 copies/mL (P < 0.01). No significant differences were observed between the groups in the rates of virological rebound, new-onset acquired immune deficiency syndrome–defining conditions, or mortality. Multivariable logistic regression identified an initial viral load ≥ 500,000 copies/mL as an independent risk factor for LLV (adjusted odds ratio, 4.735; 95% confidence interval, 1.505–14.897).ConclusionA high viral load was a significant risk factor for LLV. Large multicenter studies are required to further investigate risk factors and clinical implications of LLV in people living with HIV.

Fate and transport of viruses, bacteria and antimicrobial resistance associated with wet wipes and microplastics through wastewater treatment to coastal waters.

Monkeypox (Mpox) is a zoonotic disease that threatens global public health. Different clades of monkeypox virus (MPXV) vary in transmissibility and pathogenicity. In 2023, a Clade Ib MPXV variant emerged in the Democratic Republic of the Congo, continued to spread in parts of Africa, and subsequently spilled over to other regions, posing new challenges for outbreak prevention and control. We established stable mouse models of MPXV Clade Ib infection by intranasally infecting C57BL/6/STAT1-/-, AGB6 (C57BL/6-Ifngr1-/-Ifnar1-/-), C57BL/6, and BALB/c mice. Susceptible strains showed marked body weight loss, high viral loads in tissues, and severe histopathological lesions. RNA-seq analysis of spleens at the early stage of infection showed that differentially expressed genes were mainly enriched in interferon-mediated antiviral pathways and inflammatory cytokine-related pathways, whereas genes associated with adaptive immune responses were downregulated. Comparative analysis showed that MPXV Clade Ib caused more severe disease phenotypes than Clade IIb under the same experimental conditions, which is consistent with reported differences in clinical severity. We established reproducible mouse models for MPXV Clade Ib infection and demonstrated that Clade Ib showed greater replication capacity and pathogenicity than Clade IIb in these models. This study also provides a foundation for subsequent research on the pathogenesis of MPXV and the evaluation of antiviral efficacy.

Porcine circovirus types 2 (PCV2) and 3 (PCV3) are globally distributed pathogens associated with reproductive disorders, subclinical infections, and multifactorial disease complexes in swine. To elucidate their epidemiological and evolutionary patterns in China, we examined 8426 clinical samples collected from 28 provincial‐level regions between 2022 and 2025. PCV2 showed substantially higher prevalence than PCV3 across production stages and clinical categories and exhibited pronounced seasonal peaks in autumn. PCV2 was most frequently detected in tissue samples and presented high viral loads in systemic wasting and enteric cases, whereas PCV3 occurred at lower viral loads and was predominantly identified in swabs, semen, and milk. A total of 181 PCV2 and 106 PCV3 ORF2 sequences were obtained for genetic analysis. PCV2d was confirmed as the overwhelmingly dominant genotype nationwide, while PCV3c predominated among circulating PCV3 lineages alongside coexisting PCV3a and PCV3b clusters. Selection pressure analyses indicated that both viruses were largely shaped by purifying selection, although PCV2 harbored a greater number of positively selected sites located in surface‐exposed regions of the Cap protein. Phylodynamic inference revealed long‐term stability in the effective population size of PCV2, whereas PCV3 experienced a recent expansion followed by stabilization. Spatial phylogeographic reconstruction demonstrated a centralized diffusion pattern for PCV2, with Hebei serving as a major transmission hub, in contrast to the multicentered and geographically admixed spread of PCV3. Collectively, these findings indicate that PCV2 remains the primary pathogenic burden in Chinese swine herds. In contrast, the more diffuse dissemination of PCV3 from multiple sources warrants sustained molecular monitoring, particularly in breeding populations.

Dengue manifestations range from mild fever to fatal shock, driven by viral virulence and host responses. While Kolkata is hyperendemic, data linking specific serotypes and viral load to clinical outcomes remains limited. This prospective observational study (January 2024-June 2025) analysed 120 dengue serology-reactive patients at a Kolkata teaching hospital. Viral nucleic acid was extracted for serotyping and quantification via the molecular method. Patients were stratified by severity using World Health Organization 2009 criteria. Dengue 2 serotype (DENV-2) was dominant (45.8%), followed by dengue 3 serotype (DENV-3) (33.3%) and coinfections (20.0%). Severe cases had significantly lower mean cycle threshold (Ct) values (23.4 vs 28.1; p<0.001). Multivariate analysis identified high viral load as an independent predictor of severity (adjusted odds ratio 0.89 per unit Ct decrease, p=0.003), indicating an 11% risk increase per unit Ct decrease. Notably, DENV-3 exhibited a strong trend toward higher mortality (adjusted odds ratio 3.31, p=0.08), accounting for 53.8% of fatal cases despite lower viraemia. The study identifies a 'prevalence-virulence dissociation' where DENV-2 dominates numerically but DENV-3 drives mortality. Quantitative viral load is a robust prognostic marker. Integrating real-time molecular surveillance and Ct threshold into triage protocols is vital for mitigating fatal outcomes in hyperendemic regions.

This study describes a TaqMan qPCR assay targeting the VP2 gene for the sensitive detection and quantification of amdoparvovirus DNA in various small mammals. The assay demonstrated high specificity, a low detection limit (3.60 × 101 copies/µL), and excellent repeatability (CV < 1.57%), proving 100-fold more sensitive than conventional PCR. Applying this method to 148 fecal and tissue samples from small mammals across four zoos in Guangdong, China, revealed an overall amdoparvovirus DNA detection rate of 25.0% (95%CI: 18.6% to 32.6%), significantly higher than the 18.92% detected by conventional PCR. High viral loads were notably found in spleen, lung, and mesenteric lymph nodes of individual animals, indicating systemic distribution of viral DNA in these cases. This research provides the first molecular evidence of amdoparvovirus circulation within the sampled zoo populations in Chinese, suggesting potential exposure among captive small mammals in these facilities. However, due to the opportunistic sampling design and heterogeneous sample types, further systematic surveillance is needed to assess the true prevalence and associated risks.

ABSTRACT Despite advances in antiretroviral therapy, viral suppression rates remain suboptimal among key populations in Lagos, Nigeria. This study investigated sociodemographic and clinical predictors of viral non-suppression in these high-risk groups. A retrospective matched case-control study was conducted using clinical records and structured adherence interviews of 520 ART-experienced participants (260 virally unsuppressed cases matched 1:1 with 260 suppressed controls) across six clinics in Lagos. Bivariate analyses and multivariable conditional logistic regression identified predictors of non-suppression, adjusting for matching factors. Baseline predictors, CD4 <200 cells/μL: adjusted odds ratio [aOR] = 4.12 (95% CI: 2.87–5.91; p < 0.001) and viral load >1000 copies/mL: aOR = 6.85 (95% CI: 4.23–11.09; p = 0.001), were strongly associated with non-suppression. TB coinfection independently predicted non-suppression (aOR = 2.34, 95% CI: 1.15–4.76; p = 0.015). Adherence barriers varied across subgroups but were not independently associated with suppression status after adjustment. Programs should prioritize earlier HIV diagnosis and rapid connection to care for patients presenting with low CD4 or high viral load, integrate TB/HIV services, and provide targeted adherence support, particularly for males with TB coinfection. List of Abbreviations: AIDS: Acquired Immunodeficiency Syndrome; aOR: Adjusted Odds Ratio; ART: Antiretroviral Therapy; AUC: Area Under the Curve; CHUM: Socioeconomic barriers; CI: Confidence Interval; CRB: Clinic-Related Barriers; EAC: Enhanced Adherence Counselling; FSW: Female Sex Workers;HBV: Hepatitis B Virus; HCV: Hepatitis C Virus; HIV: Human Immunodeficiency Virus; IPV: Intimate Partner Violence; IQR: Interquartile Range; LGA: Local Government Area; LSACA: Lagos State AIDS Control Agency; MSM: Men Who Have Sex with Men; NAIIS: Nigeria HIV/AIDS Indicator and Impact Survey; NGO: Non-Governmental Organisation; PHE: Psychological Distress; PWID: People Who Inject Drugs; STI: Sexually Transmitted Infection; TB: Tuberculosis; UNAIDS: Joint United Nations Program on HIV/AIDS; VL: Viral Load; WHO: World Health Organization

Although antiviral prophylaxis is standard for lymphoma patients with chronic hepatitis B virus (HBV) infection to prevent HBV reactivation (HBVr), the optimal timing for high-risk patients (baseline HBV deoxyribonucleic acid (DNA) ≥4 log10 IU/mL) during immunochemotherapy remains unclear. A multicentre retrospective study analysed 112 chronic HBV patients among 1120 newly diagnosed diffuse large B-cell lymphoma (DLBCL) patients, stratified by baseline viral load (low: <104 IU/mL, n = 82; high: ≥104 IU/mL, n = 30). We assessed antiviral timing, virological dynamics and clinical outcomes. Antivirals (mainly entecavir) suppressed HBV DNA to undetectable levels in high-load patients (median start 1.65 × 106 IU/mL; p = 0.001). The 3-year cumulative HBVr rates were low (4.2% overall; 4.5% high vs. 4.1% low load, p = 0.955), with one fatal HBVr after discontinuation. Liver toxicity was mild (grade 1-2 transaminase elevations: 33.3%-36.7%). High and low viral load groups achieved comparable 3-year progression-free survival (80.9% vs. 70.6%, p = 0.137), overall response rates (86.7% vs. 82.9%) and complete remission rates (70.0% vs. 64.6%). Propensity score-matched analysis confirmed no significant differences in progression-free survival or HBVr. Concurrent initiation of antiviral prophylaxis with immunochemotherapy is safe and effective, preventing HBVr and enabling timely immunochemotherapy in DLBCL patients with high HBV DNA levels.