Search Results (380)

The emergence of a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus closely related to SARS-CoV and officially known as Betacoronavirus pandemicum precipitated a substantial surge in vaccine development that culminated during the global COVID-19 pandemic. At present, there are dozens of vaccines for the prevention of SARS-CoV-2 being utilized across the globe. However, only 10 of these vaccines have been authorized by the World Health Organization (WHO). These include mRNA-based, viral vector, subunit and whole-virion inactivated vaccines. At the current end of the pandemic, there has been a decline in the global vaccination rate, both for the general population and for those most at risk of severe illness from the virus. This suggests that the effectiveness of the vaccines may be waning. The decline occurs alongside a decrease in testing and sequencing for SARS-CoV-2. Furthermore, the process of tracking viruses becomes increasingly complex, thereby providing a selective advantage for SARS-CoV-2 and allowing it to evolve stealthily. In this review, we provide a comprehensive overview of viral evolution and vaccine development. We also discuss ways to overcome viral variability and test universal vaccines for all SARS-CoV-2 variants. Full article

Feline coronavirus (FCoV), the causative agent behind feline infectious peritonitis (FIP), is one of the biggest infectious threats to feline health. Despite this threat, the tissue distribution and viral RNA levels in cats infected with feline coronaviruses are poorly understood in the context of natural infection. Here, we used a two-step reverse-transcription quantitative PCR (RT-qPCR) to examine viral RNA levels from different sampling sites in both cats that have been clinically suspected of FIP and their feline housemates. We show that the distribution and amount of FCoV viral RNA does not differ between FCoV-infected cats with FIP and their feline housemates in blood, conjunctiva, or feces. Furthermore, in all FIP and non-FIP cases, viral RNA levels were higher in fecal samples than the blood. Taken together, these results show that amount of viral RNA does not differ between FCoV-infected cats with FIP and their healthy housemates in several sample types. Our results indicate a need for closer examination of FCoV pathogenesis independent of viral dissemination, including an assessment of intrahost evolution of FCoVs and FCoVs’ interactions with the feline immune system. Full article

The evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its impact on public health continue to demand attention as the virus continues to evolve, demonstrating a remarkable ability to adapt to diverse selective pressures including immune responses, therapeutic treatments, and prophylactic interventions. The SARS-CoV-2 variant landscape remains dynamic, with new subvariants continuously emerging, many harboring spike protein mutations linked to immune evasion. In this study, we characterized a panel of live SARS-CoV-2 strains, including those key subvariants implicated in recent waves of infection. Our findings revealed a significant variability in mutation patterns in the spike protein across the strains analyzed. Commercial antibodies and human convalescent plasma (HCoP) samples from unvaccinated donors were ineffective in neutralizing the most recent Omicron subvariants, particularly after the emergence of JN.1 subvariant. Using human airway epithelial cells derived from healthy bronchiolar tissue (hBAEC), we established both monoinfections and coinfections involving SARS-CoV-2, Influenza A virus H1N1 (IFAV_H1N1) and Respiratory Syncytial Virus (RSV). Assessments were conducted to compare viral infectivity and the production and release of immune mediators in the apical and basolateral compartments. Notably, Omicron KP.3.1.1 subvariant induced a more pronounced cytopathic effect in hBAEC compared to its parental strain JN.1 and even surpassed the impact observed with the ancestral wild-type virus (WA1/2020, Washington strain). Furthermore, the coinfection of KP.3.1.1 subvariant with IFAV_H1N1 or RSV did not attenuate SARS-CoV-2 infectivity; instead, it significantly exacerbated the pathogenic synergy in the lung epithelium. Our study demonstrated that pro-inflammatory cytokines IL-6, IFN-β, and IL-10 were upregulated in hBAEC following SARS-CoV-2 monoinfection with recent Omicron subvariants as well as during coinfection with IFAV_H1N1 and RSV. Taken together, our findings offer new insights into the immune evasion strategies and pathogenic potential of evolving SARS-CoV-2 Omicron subvariants, as well as their interactions with other respiratory viruses, carrying important implications for therapeutic development and public health preparedness. Full article

Background and Objectives: Coronavirus disease 2019 (COVID-19) triggers a dysregulated host response that may culminate in refractory hypoxaemic shock. Whether veno-venous ECMO modifies the inflammatory cascade more effectively in COVID-19 than in other septic states, and how it compares with conventional ventilatory support for COVID-19, remains uncertain. We compared three groups: COVID-19 patients supported with ECMO (COVID-ECMO, n = 25), non-COVID-19 septic shock patients on ECMO (SEPSIS-ECMO, n = 19) and critically ill COVID-19 patients managed without ECMO (COVID-CONV, n = 74). Methods: This retrospective study (January 2018–January 2025) extracted demographic, laboratory and clinical data at baseline, 48 h and 72 h. The primary end-point was the 72 h change in SOFA score (ΔSOFA). The secondary end-points included the evolution of interleukin-6 (IL-6), C-reactive protein (CRP), D-dimer and ferritin; haemodynamic variables; and 28 day mortality. A post hoc inverse-probability-of-treatment weighting (IPTW) sensitivity analysis adjusted for between-group severity imbalances. Results: Baseline APACHE II differed significantly (29.5 ± 5.8 COVID-ECMO, 27.4 ± 6.1 SEPSIS-ECMO, 18.2 ± 4.9 COVID-CONV; p < 0.001). At 48 h, IL-6 fell by 51.8% in COVID-ECMO (−1 116 ± 473 pg mL⁻¹) versus 32.4% in SEPSIS-ECMO and 18.7% in COVID-CONV (p < 0.001). The ΔSOFA values at 72 h were −4.6 ± 2.2, −3.1 ± 2.5 and −1.4 ± 1.9, respectively (p < 0.001). ECMO groups achieved larger mean arterial pressure rises (+16.8 and +14.2 mmHg) and greater norepinephrine reduction than COVID-CONV. The twenty-eight-day mortality was 36.0% (COVID-ECMO), 42.1% (SEPSIS-ECMO) and 39.2% (COVID-CONV) (p = 0.88). Across all patients, IL-6 clearance correlated with ΔSOFA (ρ = 0.48, p < 0.001) and with vasopressor-free days (ρ = 0.37, p = 0.002). Conclusions: ECMO, regardless of aetiology, accelerates inflammatory-marker decline and organ failure recovery compared with conventional COVID-19 management, but survival advantage remains elusive. COVID-19 appears to display a steeper cytokine-response curve to ECMO than bacterial sepsis, suggesting phenotype-specific benefits that merit confirmation in prospective trials. Full article

The continuous evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the emergence of variants of concern (VOCs) underscore the critical role of vaccination in pandemic control. These mutations not only enhance viral infectivity but also facilitate immune evasion and diminish vaccine efficacy, necessitating ongoing surveillance and vaccine adaptation. Current SARS-CoV-2 vaccines, including inactivated, live-attenuated, viral vector, protein subunit, virus-like particle, and nucleic acid vaccines, face challenges due to the immune evasion strategies of emerging variants. Moreover, other sarbecoviruses, such as SARS-CoV-1 and SARS-related coronaviruses (SARSr-CoVs) pose a potential risk for future outbreaks. Thus, developing vaccines capable of countering emerging SARS-CoV-2 variants and providing broad protection against multiple sarbecoviruses is imperative. Several innovative vaccine platforms are being investigated to elicit broad-spectrum neutralizing antibody responses, offering protection against both current SARS-CoV-2 variants and other sarbecoviruses. This review presents an updated overview of the key target antigens and therapeutic strategies employed in current SARS-CoV-2 vaccines. Additionally, we summarize ongoing approaches for the development of vaccines targeting infectious sarbecoviruses. Full article

Infectious bronchitis virus (IBV) is a chicken pathogen present in commercial poultry farms worldwide. It is classified within the species Avian coronavirus, genus Gammacoronavirus. As with other members of the family Coronaviridae, it has a single positive-sense RNA genome with 27.6 Kb and presents viral particles with a typical crown-like aspect due to the spike (S) transmembrane glycoprotein. IBV has a remarkable capacity for genetic recombination and mutation, resulting in many genotypes and antigenic variants over evolutionary time. Currently, it is classified into nine genetic types (GI to GIX) and 41 (1 to 41) lineages disseminated worldwide. In South America, IBV was first identified in early commercial poultry production ventures in Brazil in the 1950s. Since then, this virus has been frequently detected in commercial South American poultry farms, being classified into serotypes in the first decades and genotypes more recently. IBVs of the Massachusetts (Mass) serotype were initially detected and vaccine strains of this serotype were used extensively on commercial poultry farms. Other serotypes/genotypes were identified later, with almost all of them classified in the current genetic type I (GI). In addition, five GI lineages (GI-1, -11, -13, -16, and -23) have been associated with the main infectious bronchitis outbreaks in the continent, with some variations in the occurrence according to the countries and the period of time. Molecular epidemiological surveillance of IBV genetic types and lineages is necessary to anticipate potential outbreaks, revealing patterns of viral evolution and dissemination, as well as to guide the selection of appropriate vaccine strains and immunization programs. Full article

Background: South Korea was one of the first countries to experience the Coronavirus disease (COVID-19) epidemic, and the regional-level trends and patterns in the incidence and case-fatality rates have been observed to evolve with time. This study established yearly spatiotemporal evolution patterns of COVID-19 by region and identified possible regional risk factors accounting for the observed spatial variations. Methods: COVID-19 data between 20 January 2020 and 31 August 2023 were collected from the Korean Centers for Disease Prevention and Control (KCDA). We generated epidemic curves and calculated the yearly incidence and case-fatality rates for each region. In addition, choropleth maps for the location quotient of cases and deaths to visualize yearly regional intensities were generated and the Moran’s I calculated. Associations between the incidence and case-fatality rates with regional risk factors were estimated using regression models. All analyses were performed in R version 4.4.2. Results: We noted a significant difference in the incidence rate by year, with 2022 recording the highest for all regions. A consistent and significant spatial autocorrelation for cases and deaths across all years was observed with Moran I values above 0.4 (p < 0.05). There was a positive association of COVID-19 incidence rates with the population density (RR = 0.02, CI: 0.01–0.04, p = 0.03), percentage aged 60 years and above (RR = 0.03, CI: 0.01–0.05, p = 0.01), smoking prevalence (women) (RR = 0.79, CI: 0.54–1.04, p = 0.01), and diabetes prevalence (women) (RR = 0.51, CI: 0.32–0.71, p = 0.04). Conclusions: The spatiotemporal evolution patterns of COVID-19 in Korea consisted of oscillating hot and cold spots across the pandemic period in each region. These findings provide a useful reference to the government as it continues with the routine surveillance of COVID-19 across the country. Full article

Background/Objectives: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused post-acute sequelae, especially for people with pre-existing conditions, including chronic kidney disease (CKD), which may impact the cardiovascular system. Yet, despite the preliminary description of the general population’s long-COVID-19 consequences, data on CKD patients is scarce. The aim of this study was to investigate the longitudinal effects of COVID-19 on echocardiographic parameters of cardiac function and on cardiac biomarkers in patients with CKD. Methods: A total of 163 patients were included in this observational prospective trial (listed under NCT05125913 code): 88 in the COVID-19 group and 75 in the control group. The serial echocardiographic characteristics in patients who survived beyond one year, focused on left and right ventricular systolic function, together with cardiac biomarkers evolution, were compared between the two groups. Results: At baseline, there were no significant differences in left ventricular (LV) function parameters, except for a higher Tei Index in the COVID-19 group (p < 0.01). Right ventricular (RV) systolic dysfunction was more frequent in the COVID-19 group, with worse fractional area change (FAC) (p = 0.01), RV free wall longitudinal strain (RVFWLS) (p = 0.01), and RV Tei Index (p = 0.01). Over time, the control group showed a decline in LV ejection fraction (EF), while the COVID-19 group slightly improved. RV global systolic function was better preserved in the COVID-19 group. To the best of our knowledge, this is the first study that demonstrates a statistically significant increase in LAVi in patients with COVID-19. Conclusions: Prior COVID-19 infection influenced the trajectory of LV and RV function in CKD patients over 12 months, suggesting potential transient myocardial adaptations. While overall cardiac function did not differ significantly between groups, COVID-19 survivors exhibited better preservation of some ventricular function parameters. Full article

Background/Objectives: The rapid evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the emergence of variants with enhanced transmissibility and immune evasion, challenging existing vaccines. This study aimed to evaluate the immunogenicity and protective efficacy of inactivated bivalent vaccine formulations incorporating the ancestral SARS-CoV-2 strain (ERAGEM) with either Delta or Omicron (BA.5) variants. Methods: Bivalent vaccine formulations were prepared using beta-propiolactone-inactivated SARS-CoV-2 antigens and administered to K18-hACE2 transgenic mice. Following prime and booster immunizations, neutralizing antibody titers and viral loads were assessed through ELISA, microneutralization assays, and quantitative PCR. Mice were challenged with the respective variants, and the survival rates, temperature, and body weight changes were monitored for 21 days. Results: Both vaccine formulations elicited significant increases in neutralizing antibody titers post-booster immunization. The ERAGEM + Delta group demonstrated geometric mean titers (GMTs) of 6938.1 and 4935.0 for the ancestral and Delta variants, respectively, while the ERAGEM + Omicron (BA.5) group achieved GMTs of 16,280.7 and 24,215.9 for the ancestral and Omicron (BA.5) variants. Complete survival (100%) was observed in all the vaccinated groups post-challenge, with no detectable viral titers in the lungs and substantial reductions in the nasal turbinate viral loads compared to the unvaccinated controls. Conclusions: The bivalent inactivated vaccines demonstrated strong immunogenicity and complete protection against severe disease in preclinical models. These findings indicate the potential of bivalent vaccine strategies in addressing antigenic diversity and preparing for future pandemics caused by rapidly evolving pathogens. Full article

Introduction: COVID-19 is a respiratory disease caused by the SARS-CoV-2 virus, which belongs to the coronavirus family. SARS-CoV-2 is related to other viruses that cause severe acute respiratory syndrome. The emergence of cases of pneumonia of unknown origin triggered the largest viral pandemic in modern times, presenting major challenges to global public health. Objective: To analyze the evolution of the COVID-19 pandemic in the state of São Paulo from 2020 to 2023, focusing on trends in incidence, mortality, and lethality. Methods: Ecological study of time series of incidence, mortality and lethality by COVID-19 in the state of São Paulo using Prais-Winsten regression considering the Weekly Percentage Change (WPC) and probability values (p), considering a significance level of 95% (95% CI). To ensure the reliability of the entered data, double-blind typing was performed by different researchers in the same database extracted from the 2024 Ministry of Health Coronavirus dashboard. Results: From February 2020 and the end of December 2023, 6,763,310 accumulated cases and 182,254 deaths were recorded. Stationary trends were observed for the year 2022, with a reduction in incidence and mortality in the year 2023. However, the epidemiological variable lethality showed a stationary trend. Conclusion: The analysis of the trends in incidence, mortality, and lethality revealed variable dynamics over time, with emphasis on the significant reduction of these indicators in 2023. Full article

Feline infectious peritonitis virus (FIPV) remains as one of the leading causes of morbidity and mortality in young cats from shelters and catteries worldwide. Since little is known about the molecular characteristics of currently circulating FIPV strains in Long Island, New York, samples from two shelter cats submitted to the Pathology Diagnostic Services of the Long Island University College of Veterinary Medicine, with gross and microscopic lesions consistent with those of FIP were processed for virus isolation, molecular characterization and full-length genome decoding. The younger shelter cat, a 1-year-old male (A15) was found dead without previous signs of illness. Postmortem examination revealed gross and microscopic lesions characterized by vasculitis, necrosis, hemorrhage, and pyogranulomatous inflammation confined to the colon and associated lymph nodes. The second cat, a 7-year-old spayed female (A37) had an identical clinical history and similar but widespread lesions, including fibrinous peritoneal effusion, cecal, colonic, renal, and hepatic involvement. The gross and microscopic diagnosis of FIP in these cats was confirmed by immunohistochemistry (IHC) demonstration of feline coronavirus antigen using mouse anti-FIPV3-70 monoclonal antibody. Virus isolation from saved frozen kidney and colon tissue was performed through several subsequent blind passages in MDCK and Vero cell lines. Confirmation of the FIPV isolation was done through qRT-PCR, IFA, western blot using N protein antibodies, and NGS of the full-length genome sequencing. The full-length genome sequences of the virus isolate from the two cats were decoded using next-generation sequencing (NGS) and deposited in the GenBank as accession numbers PQ192636 and PQ202302. The genome size of these isolates was (29355 and 29321) nucleotides (nt) in length, respectively. While their genome organization was consistent with other FIPV genomes as follows (5’UTR-ORF1ab-S-3abc-M-E-7b-3’UTR-3’), marked differential mutations were observed in the ORF1a/b, S, 3Abc, and 7b protein genes of the two FIPV isolates. One notable deletion of 34 nucleotides was observed in the 7b genes of one of these isolates but was absent in the other. We confirmed the potential recombination events during the evolution of those two FIPV field isolates with the potential parent virus as FECoV-US isolated in 1970 and the potential minor parent as the Canine coronavirus. Our results provide a comprehensive molecular analysis of two novel FIPV isolates causing fatal disease in shelter cats from Long Island. Diagnostic surveillance with molecular characterization and sequencing analysis of circulating FIPV strains within animal shelters may help early detect unique emerging clinical and pathological manifestations of the disease and develop more targeted prophylactic and therapeutic approaches to control it. Full article

Human outbreaks of Middle East respiratory syndrome coronavirus (MERS-CoV) are more common in Middle Eastern and Asian human populations, associated with clades A and B. In Africa, where clade C is dominant in camels, human cases are minimal. We reviewed 16 studies (n = 6198) published across seven African countries between 2012 and 2024 to assess human MERS-CoV cases. We also analyzed data from four cohort studies conducted in camel-keeping communities between 2018 and 2024 involving camel keepers, camel slaughterhouse workers, and hospital patients with acute respiratory illness (ARI). The analysis showed a pooled MERS-CoV prevalence of 2.4% (IQR: 0.6, 11.4) from 16 publications and 1.14% from 4 cohort studies (n = 2353). Symptomatic cases were rarely reported, with most individuals reporting camel contact, and only 12% had travel history to the Middle East. There was one travel-associated reported death, resulting in a mortality rate of 0.013%. The findings suggest a low camel-to-human transmission of clade C MERS-CoV in Africa. Ongoing research focuses on genomic comparisons between clade C and the more virulent clades A and B, alongside the surveillance of viral evolution. This study highlights the need for continuous monitoring but indicates that MERS-CoV clade C currently poses a minimal public health threat in Africa. Full article

Porcine epidemic diarrhea (PED) is caused by the PED virus, with genogroup 2 (G2), comprising G2a and G2b, being the primary contributors to outbreaks worldwide. In Thailand, G2a was the only virulent strain identified until the emergence of the first G2b strain in 2014, followed by additional G2b strains in 2015–2016, particularly those closely related to virulent strains from China. This led to increased awareness of more frequent and complex outbreaks. This study examined farms affected by G2a and G2b strains, both employing planned exposure of sows to intestines from G2a-affected piglets, a traditional practice in Thailand. The analysis focused on the milk and colostrum profiles of sows, including viral neutralization and ELISA methods, as well as histopathological assessments of piglet intestinal villi. Additionally, a novel G2b strain was sequenced for phylogenetic and protein structure analyses. The results revealed no significant differences in colostrum and milk profiles between the farms. However, piglets infected with G2b showed significantly more severe intestinal damage. A unique insertion in the protein structure of the novel G2b strain led to the identification of a new epitope and potential changes in viral properties. This study highlights the importance of monitoring emerging strains and provides valuable insights for enhancing preventive strategies and advancing phylogenetic research. Full article

Coronavirus disease 2019 (COVID-19) has been associated with a significant fatality rate and persistent evolution in immunocompromised patients. In this prospective study, we aimed to determine the duration of excretion of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 37 Tunisian patients with hematological malignancies (40.5% with lymphoma and 37.8% with leukemia). In order to investigate the accumulation of viral mutations, we carried out genetic investigation on longitudinal nasopharyngeal samples using RT-PCR and whole-genome sequencing. Patients’ samples were collected until the RT-PCR results became negative. SARS-CoV-2 infection was symptomatic in 48.6% of cases with fever, and cough was symptomatic in 61% of cases; the mortality rate was estimated to be 13.5%. The duration of viral RNA shedding ranged from 7 to 92 days after onset; it exceeded 18 days in 79.4% of cases. An intermittent PCR positivity was observed in two symptomatic patients. Persistent PCR positivity, defined as the presence of viral RNA for more than 30 days, was found in 51.4% of cases. No significant differences were observed for age, sex, type of hematological malignancy, or COVID-19 evolution between this group and a second one characterized by non-persistent PCR positivity. Lymphopenia was an independent predictor of prolonged SARS-CoV-2 RNA detection (p = 0.04). Three types of variants were detected; the most frequent was the Omicron. Globally, the mean intra-host variability in the SARS-CoV-2 genome was 1.31 × 10⁻³ mutations per site per year; it was 1.44 × 10⁻³ in the persistent group and 1.3 × 10⁻³ in the non-persistent group. Three types of mutations were detected; the most frequent were nucleotide substitutions in the spike (S) gene. No statistically significant difference was observed between the two groups as to the type and mean number of observed mutations in the whole genome and the S region (p = 0.650). Sequence analysis revealed the inclusion of one to eight amino acid-changing events in seventeen cases; it was characterized by genetic stability from the third to the twentieth day of evolution in six cases. For the two patients with intermittent PCR positivity, sequences obtained from samples before and after negative PCR were identical in the whole genome, confirming an intra-host evolution of the same viral strain. This study confirms the risk of persistent viral shedding in patients with hematological malignancies. However, persistence of PCR positivity seems to be correlated only with a continuous elimination of viral RNA debris. Additional studies based on cell culture analysis are needed to confirm these findings. Full article

The global epidemic of bovine coronavirus (BCoV) has caused enormous economic losses. The characterisation and genetic composition of endemic strains in Southwest China remain elusive. This study aimed to fill this gap by isolating three BCoV strains from this region and sequencing their whole genomes. To elucidate the genetic evolution and characterisation of the prevalent strains, the results of BCoV sequences were compared in GenBank, with a focus on genetic evolution, mutation, and recombination patterns. The results showed close homology between strains NN190313 and NN230328, while strain NN221214 showed less similarity to these two strains but clustered with the French strain of the European branch. Intriguingly, NN190313 and NN230328 were grouped with goat-derived BCoV strains from Jiangsu Province in Eastern China in the Asian–American branch. In addition, recombination analyses revealed significant signals between NN230328 and either a Chinese goat-derived strain (XJCJ2301G) or a Shandong strain (ShX310). This study highlights the importance of monitoring cross-species transmission between cattle and goats, especially in the mountainous areas of Southwest China where mixed farming occurs, and thus, the monitoring of cross-species transmission between cattle and goats is important for preventing new public health challenges, providing important insights for research on cross-species transmission, early prevention, and control measures, with potential applications in vaccine development. Full article