Search Results (216)

Acute respiratory infections (ARIs) continue to pose a major global health threat, particularly among vulnerable populations. These infections often present with similar clinical symptoms, complicating accurate diagnosis and facilitating unmonitored transmissions. Genomic surveillance has emerged as an invaluable tool for pathogen identification and monitoring of such infectious pathogens; however, its implementation is frequently limited by high costs. The widespread use of high-throughput sequencing during the COVID-19 pandemic has created an opportunity to repurpose existing genomic platforms for broader respiratory virus surveillance. In this study, we evaluated the feasibility of adapting the Illumina COVIDSeq assay—initially designed for SARS-CoV-2 whole-genome sequencing—for use with Influenza A/B, Respiratory Syncytial Virus (RSV), and Rhinovirus. Positive control samples were processed using two approaches for library preparation: four virus-specific multiple workflows and a combined rapid workflow. Both workflows incorporated pathogen-specific primers for amplification and followed the Illumina COVIDSeq protocol for library preparation and sequencing. Sequencing quality metrics were analysed, including Phred scores, read length distribution, and coverage depth. The study did not identify significant differences in genome coverage and genetic diversity metrics between workflows. Genome Detective consistently identified the correct species across both methods. The findings of this study demonstrate that the COVIDSeq assay can be effectively adapted for multi-pathogen genomic surveillance and that the combined rapid workflow can offer a cost- and labour-efficient alternative with minimal compromise to data quality. Full article

We investigated respiratory virus epidemiology in older adults across pre-pandemic (2007–2019), pandemic (2020–2022), and post-pandemic (2023–2024) periods, focusing on how public health interventions shaped surveillance, prevalence, and sex-specific trends. We conducted a retrospective cross-sectional study at a 1000-bed tertiary hospital in the Republic of Korea during 2007–2024, analyzing 4692 nasopharyngeal swab specimens collected from adults aged ≥ 65 years with suspected respiratory infections during 2007–2024. The specimens were tested for 15 respiratory viruses using multiplex real-time polymerase chain reaction. The outcomes included virus-specific detection rates and seasonal, sex-based and temporal trends before and after the COVID-19 pandemic. During the pre-pandemic period, older adults accounted for 13.2% of the tested individuals, which significantly increased to 52.0% in the later periods. Influenza A was the most frequently detected virus, followed by rhinovirus and human metapneumovirus. Influenza, RSV A/B, and coronaviruses 229E and OC43 showed peak positivity in winter, parainfluenza virus type 3 peaked in summer, and rhinovirus circulated year-round. Virus circulation was markedly suppressed during 2020–2022 and partially rebounded during 2023–2024. This study highlights the shift in diagnostic access and epidemiologic patterns of respiratory virus infections in older adults following the COVID-19 pandemic. Full article

Respiratory syncytial virus (RSV) remains a leading cause of pneumonia in young children in Mexico and worldwide. To investigate RSV dynamics in Mexico, we conducted a multicenter study from August 2021 to July 2023 in six hospitals across five States, analyzing respiratory samples from children under five years with pneumonia. Multiplex RT-PCR identified 203 RSV-positive cases, of which 123 were RSV-B and 80 RSV-A. Interestingly, 77% of the collected samples showed evidence of coinfection with other respiratory pathogens, with rhinovirus, Haemophilus influenzae, and Streptococcus pneumoniae being the most common. Also, RSV-B dominated in 2021–2022, whereas RSV-A prevailed in 2022–2023, mirroring trends observed in the United States. Sequences of the genes encoding G and F proteins showed that RSV-A lineages were more diverse, with A.D.1, A.D.1.8, and A.D.5.2 being frequently detected. In contrast, nearly all RSV-B sequences belonged to lineage B.D.E.1. Finally, ancestral state inference suggests repeated introductions from the USA and other North American countries, with limited evidence of sustained local circulation. These findings show different trends in RSV circulation between two consecutive seasons and the importance of genomic surveillance to monitor RSV diversity, evaluate vaccine impact, and inform public health strategies in Mexico’s evolving post-pandemic respiratory virus landscape. Full article

Background: The current assessment method of the protective efficacy of adjuvanted vaccines remains slow and labor-intensive, hindered by prolonged immunization protocols and complex assays. Methods: To overcome this bottleneck, we demonstrate that early segregated cellular biomarkers enable rapid prediction of protection, using a respiratory syncytial virus (RSV) pre-fusion F (pre-F) protein model with diverse adjuvants in mice. Results: We identified that germinal center (GC) B cell responses (Days 7 and 9 post-immunization) strongly aligned with protective efficacy, except for Alum, which achieved MF59-level protection despite lower GC responses. Crucially, follicular dendritic cell (FDC) abundance at day 7 universally predicted protection across all adjuvants, including Alum, drastically shortening discovery time and effort from at least 4–6 weeks to within 1 week. Conclusions: FDCs and GC B cells serve as complementary early biomarkers that accurately forecast vaccine efficacy. This approach could potentially reduce the need for prolonged immunization regimens by cellular profiling on days 7–9, offering a modest step toward streamlining adjuvant selection and informing vaccine design. Full article

Wastewater-based epidemiology is a robust, scalable, cost-effective, and high-performing tool to monitor and predict SARS-CoV-2 trends. We aimed to investigate whether this approach could be applied to influenza A/B viruses and respiratory syncytial virus (RSV) in Marseille, southern France. Wastewater concentrations of SARS-CoV-2, influenza A/B viruses, and RSV in Marseille were monitored by qPCR between January 2021 and October 2024. These concentrations were compared with the diagnosis numbers for the three viruses collected at public hospitals in Marseille, using cross-correlation analyses. The Granger causality test was used to determine whether wastewater concentrations can predict the number of clinical cases. SARS-CoV-2 and influenza virus concentrations in wastewater preceded the rise in the incidence of patient diagnoses by a lag of five days and nine/ten days, respectively. In contrast, for RSV, the rise in incidence of clinical cases preceded that of wastewater concentrations. We conclude that wastewater-based epidemiology is a powerful tool to monitor the level of circulation of these viruses independently of tests carried out on people. It enables earlier alerts than monitoring patients for SARS-CoV-2 and influenza symptoms. However, for RSV, it does not provide an early warning, and clinical data-based surveillance appears to be more suitable. Full article

Background: Respiratory syncytial virus (RSV) remains a leading cause of respiratory illness globally, with limited vaccine options, particularly for infants and high-risk populations. This study investigates Cyclosporin A (CsA), traditionally an immunosuppressant, as a novel adjuvant to enhance RSV-specific immunity. Methods: BALB/c mice were subcutaneously immunized with RSV G protein co-administered with varying Cyclosporin A doses, challenged intranasally with RSV, and analyzed for RSV-specific humoral immunity and mechanistic Treg-dependent B-cell responses. Results: We demonstrate that co-administration of CsA with the RSV G protein (G+CsA) dose-dependently boosts RSV-specific IgG and neutralizing antibodies, with selective augmentation of IgG1 and IgG2 subclasses. Mechanistically, G+CsA induces regulatory T cells (Tregs) expressing CD40L and IL-10, which directly promote B-cell activation, proliferation, and plasma cell differentiation. Depletion of Tregs or neutralization of IL-10/CD40L abrogated antibody production, confirming these pathways as critical mediators. Notably, G+CsA-induced Tregs adopt a helper phenotype distinct from conventional Tregs, balancing immune enhancement and homeostasis. Conclusions: CsA demonstrates dual adjuvant properties by enhancing RSV-specific neutralizing IgG titers through Treg-driven B-cell activation, offering a potential strategy to optimize vaccine-induced humoral immunity. Full article

Background: Respiratory viral infections pose a major global health burden, and molecular diagnostics such as Real-Time RT-PCR have revealed frequent co-infections. However, precise quantification of viral RNA remains challenging. Digital PCR (dPCR) offers absolute quantification without standard curves and may improve diagnostic accuracy. This study compares dPCR and Real-Time RT-PCR in detecting and quantifying influenza A, influenza B, respiratory syncytial virus (RSV), and SARS-CoV-2 during the 2023–2024 tripledemic. Methods: A total of 123 respiratory samples were analysed and stratified by cycle threshold (Ct) values into high, medium, and low viral load categories. Both dPCR and Real-Time RT-PCR were used to quantify and compare viral loads across these categories. Results: dPCR demonstrated superior accuracy, particularly for high viral loads of influenza A, influenza B, and SARS-CoV-2, and for medium loads of RSV. It showed greater consistency and precision than Real-Time RT-PCR, especially in quantifying intermediate viral levels. Conclusions: These findings highlight the potential of dPCR to enhance respiratory virus diagnostics and support a better understanding of co-infection dynamics. Nonetheless, its routine implementation is currently limited by higher costs and reduced automation compared to Real-Time RT-PCR. Full article

Background/Objectives: The concurrent circulation of SARS-CoV-2 with influenza A and B viruses and respiratory syncytial virus (RSV) represents a new diagnostic challenge in the post-COVID-19 area, especially considering that these infections have overlapping clinical presentations but different approaches to treatment and management. Multiplexed molecular testing on point-of-care platforms that focus on the simultaneous detection of multiple respiratory viruses in a single tube constitutes a useful approach for diagnosis of respiratory infections in decentralized clinical settings. This study evaluated the analytical performances of the VitaSIRO solo™ SARS-CoV-2/Flu/RSV Assay performed on the VitaSIRO solo™ Instrument (Credo Diagnostics Biomedical Pte. Ltd., Singapore, Republic of Singapore). Methods: With a view to accreditation, the criteria of the 2022-revised EN ISO 15189:2022 norma were applied for the retrospective on-site verification of method using anonymized respiratory specimens collected during the last 2024–2025 autumn–winter season in France. Results: Usability and satisfaction were comparable to current reference point-of-care platforms, such as the Cepheid GeneXpert^® Xpress System (Cepheid Diagnostics, Sunnyvale, CA, USA). Repeatability and reproducibility (2.34–4.49% and 2.78–5.71%, respectively) demonstrated a high level of precision. The platform exhibited a low invalid rate (2.9%), with most resolving on retesting. Analytical performance on 301 clinical samples showed high overall sensitivities: 94.8% for SARS-CoV-2 (Ct ≤ 33), 95.8% for influenza A and B viruses, 95.2% for RSV, and 95.4% for all viruses. Specificities were consistently high (99.2–100.0%). False negatives (2.6%) were predominantly associated with high Ct values. Agreement with the comparator reference NeuMoDx™ Flu A-B/RSV/SARS-CoV-2 Vantage Assay (Qiagen GmbH, Hilden, Germany) was almost perfect (Cohen’s κ 0.939–0.974), and a total of 91.1%, 94.8%, and 100.0% of Ct values were within the 95% limits of agreement for the detection of SARS-CoV-2, influenza A and B viruses, and RSV, respectively, by Bland–Altman analyses. Passing–Bablok regression analyses demonstrated good Ct values correlation between VitaSIRO solo™ and NeuMoDx™ assays, with a slight, non-significant, positive bias for the VitaSIRO solo™ assay (mean absolute bias +0.509 to +0.898). Conclusions: These findings support VitaSIRO solo™ Instrument as a user-friendly and reliable point-of-care platform for the rapid detection and differentiation of SARS-CoV-2, influenza A and B viruses, and RSV responding to the EN ISO 15189:2022 criteria for accreditation to be implemented in hospital or decentralized settings. Full article

Since December 2019, the COVID-19 pandemic caused by SARS-CoV-2 has reached approximately 769 million people, leading to more than 7 million deaths worldwide. Faced with the possibility of other respiratory pathogens co-infecting patients and modifying their clinical response to SARS-CoV-2, some researchers have explored this line of investigation. The relationship between these co-infections remains unclear, underscoring the need to deepen our understanding of interactions among pathogens and between pathogens and the host. Thus, the present study employed RT-qPCR to assess the presence of Human Adenovirus (HAdV), Influenza A (Flu A), Influenza B (Flu B), Human Metapneumovirus (HMPV), Respiratory Syncytial Virus (RSV), Human Rhinovirus (HRV), and Parainfluenza Virus (PIV). Nasopharyngeal samples (187) from adult patients exhibiting respiratory symptoms were collected between February 2021 and November 2022 at the University Hospital Polydoro Ernani de São Thiago in Florianópolis, SC, Brazil. The present findings revealed that 25.16% of samples tested positive for non-SARS-CoV-2 respiratory viruses (29.8%—HRV; 5.3%—PIV; 4.3%—RSV; and 1.1%—HMPV). In the 74.84% of SARS-CoV-2-positive patients, co-infection was observed in 9.7% of patients, with 7.5% being HRV, 1.1% HAdV, and 1.1% Influenza A. Since co-infections can potentially alter patient prognoses and impact local epidemiological dynamics, this study highlights the significance of ongoing monitoring and epidemiological assessment through genomic surveillance of other clinically relevant respiratory pathogens. Full article

Resveratrol (RSV), a polyphenol found in a variety of berries and wines, is known for its anti-inflammatory, anticancer, and antioxidant properties. It has been suggested that RSV may play a role in the regulation of metabolic disorders, including diabetes and insulin resistance. However, in recent years, it has been reported to completely inhibit Akt kinase function in liver cells. Akt is a central protein involved in the metabolic function of insulin and is regulated by the phosphatidylinositol-3-kinase (PI3K) pathway. In this study, we examined the effect of RSV on insulin-induced insulin receptor (IR) phosphorylation and proteins involved in the PI3K/Akt pathway in a hepatic cell model, clone 9 (C9), and in hepatoma cells, Hepa 1-6 (H1-6). In both cell lines, RSV inhibited tyrosine phosphorylation of IR and insulin-induced activation of Akt. We also evaluated the effect of RSV on the activation of protein tyrosine phosphatase 1B (PTP1B), which is associated with IR dephosphorylation, and found that RSV increased PTP1B-Tyr¹⁵² phosphorylation in a time- and concentration-dependent manner. Furthermore, we found that the protein kinase C (PKC) inhibitors BIM and Gö6976 prevented the inhibition of Akt phosphorylation by RSV and increased the phosphorylation of Ser/Thr residues in IR, suggesting that PKC is involved in the inhibition of the insulin pathway by RSV. Thus, classical PKC isoforms impair the PI3K/Akt pathway at the IR and GSK3 and GS downstream levels; however, IRS-Tyr⁶³² phosphorylation remains unaffected. These results suggest that RSV can lead to insulin resistance by activating PTP1B and PKC, consequently affecting glucose homeostasis in hepatic cells. Full article

Background/Objective: Maternal immunization is highly recommended, particularly in developed countries. However, its awareness among pregnant women in Japan remains low. This study aimed to assess the awareness and attitudes toward maternal immunization among pregnant women in Japan and to identify the factors that may promote its acceptance. Methods: We conducted a cross-sectional questionnaire survey among pregnant women attending antenatal checkups at nine facilities in Kanagawa Prefecture, Japan, from August 2024 to January 2025. The survey assessed knowledge and intention regarding maternal immunization for influenza, pertussis, respiratory syncytial virus (RSV), and group B streptococcus (GBS) as well as attitudes toward vaccination costs and information sources. Results: Overall, 523 respondents were included in this study. The overall awareness of maternal immunization was 16%. Willingness to receive vaccinations during pregnancy was reported for influenza (68%), pertussis (58%), RSV (59%), and GBS (71%). A common reason for vaccine hesitancy included uncertainty about its effects on the fetus. The key factors associated with vaccine acceptance were higher educational attainment and prior knowledge of maternal immunization. Regarding costs, most respondents were willing to pay up to JPY 5000 (approximately USD 35). The most frequently prioritized sources were explanations from physicians, followed by explanations from midwives. Conclusions: Despite low awareness, vaccination intention was comparable to that reported in other countries. Points that may contribute to improved vaccine uptake were also identified. These findings may lead to the prevention of infectious diseases in newborns and infants in Japan and possibly improve public health. Full article

Background: Respiratory syncytial virus (RSV) bronchiolitis is a leading cause of lower respiratory tract infections in children under two years of age. NF-κB is a key transcription factor in antiviral and inflammatory responses. This study investigates the expression of NF-κB mRNA in both blood and buccal swab samples of pediatric patients hospitalized for RSV bronchiolitis, comparing levels at admission and discharge. Methods: Paired peripheral blood and buccal swab samples were collected from pediatric patients (n = 85) at hospital admission and discharge. Quantitative real-time PCR was used to assess NF-κB mRNA levels. Results: NF-κB mRNA levels significantly decreased in blood between admission and discharge (p < 0.05), while no significant change was observed in buccal swabs. Conclusions: These results suggest a compartment-specific regulation of NF-κB, with systemic inflammatory resolution at discharge and persistent or distinct mucosal immune activity. Understanding these dynamics may improve our approach to monitoring and treating RSV bronchiolitis. Full article

Background/Objectives: Concurrent outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A and B viruses (IAV/IBV), and respiratory syncytial virus (RSV) necessitate rapid and precise differential laboratory diagnostic methods. This study aimed to evaluate the multiplex molecular diagnostic performance of the geneLEAD VIII system (Precision System Science Co., Ltd., Matsudo, Japan), a fully automated sample-to-result precision instrument, in conjunction with the VIASURE SARS-CoV-2, Flu & RSV Real Time PCR Detection Kit (CerTest Biotec, S.L., Zaragoza, Spain). Methods: The specific detection capabilities of SARS-CoV-2, IAV/IBV, and RSV genes were evaluated using virus-spiked saliva and nasal swab samples. Using saliva samples, the viral titer detection limits of geneLEAD/VIASURE and manual referent singleplex RT-qPCR assays were compared. The performance of geneLEAD/VIASURE in analyzing single- and multiple-infection models was scrutinized. The concordance between the geneLEAD/VIASURE and the manual assays was assessed. Results: The geneLEAD/VIASURE successfully detected all the virus genes in the saliva and nasal swab samples despite some differences in the Ct values. The viral titer detection limits in the saliva samples for SARS-CoV-2, IAV, IBV, and RSV using geneLEAD/VIASURE were 10⁰, ≤10⁻², 10⁰, and 10² TCID₅₀/mL, respectively, compared to ≤10⁻¹, ≤10⁰, ≤10⁰, and ≤10⁴ TCID₅₀/mL, respectively, in the manual assays. geneLEAD/VIASURE yielded similar Ct values in the single- and multiple-infection models, with some exceptions noted in the triple-infection models when low titers of RSV were spiked with high titers of the other viruses. The concordance between geneLEAD/VIASURE and the manual assays was high, with Pearson’s R² values of 0.90, 0.85, 0.92, and 0.95 for SARS-CoV-2, IAV, IBV, and RSV, respectively. Conclusions: geneLEAD/VIASURE is a reliable diagnostic tool for detecting SARS-CoV-2, IAV/IBV, and RSV in single- and multiple-infection scenarios. Full article

Macrophages are a principal pulmonary source of type I and III interferons (IFNs), initiating and coordinating the early antiviral response to respiratory viral infections. Yet the contribution of macrophage-derived IFNs to host defense during human metapneumovirus (HMPV) infection remains poorly defined. Here, we use human primary monocyte-derived macrophages (MDMs) and THP-1-derived macrophages to analyze the IFN responses induced by HMPV compared to its closely related human pneumovirus, respiratory syncytial virus (RSV). We show that HMPV induced a robust response of type I and type III IFNs and ISGs, whereas RSV elicited only a modest, delayed IFN response despite strong IRF activation; instead, RSV preferentially activates NF-κB and exhibits a pronounced proinflammatory cytokine output. Our results highlight the role of macrophages as key modulators of the IFN and proinflammatory responses during HMPV and RSV infection. Full article

The Bacillus Calmette-Guérin (BCG) vaccine confers broad, non-specific immunity that may bolster defenses against respiratory viruses. While NOD2 (nucleotide-binding oligomerization domain-containing protein 2)-driven pathways are central to innate immune responses, the contribution of surface receptor modulation on monocytes to shaping these responses remains underexplored. We analyzed whole-blood cultures from BCG-vaccinated Polish children, stratified by serostatus to SARS-CoV-2 and RSV, and stimulated for 48 h with live BCG, purified viral antigens, or both. RT-qPCR quantified mRNA levels of NOD2 and key cytokines (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, TNF), while flow cytometry assessed CD14, HLA-DR, CD11b, and CD206 expression. Co-stimulation with BCG + RSV elicited the strongest transcriptional response, notably a 2–4-fold upregulation of NOD2, IL-1β, and IL-6 versus RSV alone. In SARS-CoV-2(+) donors, RSV alone induced higher NOD2 expression than BCG or BCG + RSV, while IL-2 peaked following BCG + SARS-CoV-2. Across conditions, NOD2 positively correlated with IL-4 and IL-6 but negatively correlated with IL-1β in SARS-CoV-2 cultures. Viral antigens increased CD14 and HLA-DR on monocytes, suggesting activation; CD206 rose only in dual-seropositive children. Our findings indicate that BCG stimulation affects pediatric antiviral immunity through NOD2-related cytokine production and induction of a CD14⁺HLA-DR⁺ phenotype, supporting its potential role in boosting innate defenses against respiratory pathogens. Full article