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The Network of National COVID-19 Data Portals: public health equity through collaboration.

The network of the national COVID-19 Data Portals was developed and linked to the COVID-19 Data Portal (https://www.covid19dataportal.org/)inresponsetothe need for rapid data sharing and analysis during the 2020-2022 SARS-CoV-2 pandemic. Built on open-source code developed by the Swedish COVID-19 Data Portal (now the Swedish Pathogens Portal, www.pathogens.se) the network included 12 national portals addressing demand for local open data sharing and access, across data types and resources. It provides a robust case study of national initiatives for FAIR (Findable, Accessible, Interoperable and Reusable) resources and a foundation for future pandemic preparedness across pathogens globally. In this paper we outline the structure of the origins of the network of National COVID-19 Datal Portals, the technical aspects and code originating from the Swedish Portal and provide an overview of the services and tools offered by each Portal. The paper showcases the process and operation of four Portals: Sweden, Poland, Spain, Norway and The Netherlands. In this study, we observe that pandemic response greatly benefits from an established infrastructure that can be quickly mobilised, developed and extended. Collaborations and preparation built on solid foundations over several years, supported by investment in the form of national and international research grants, is key for sustainability, continuation and readiness to deploy such efforts.

COVID-19

Global vaccine readiness: equity-by-design in pandemic preparedness and response.

INTRODUCTION: COVID-19 showed that rapid vaccine development and roll-out, while lifesaving, can still yield large, avoidable harms when equity is not considered from the outset. Disparities in vaccine timing and coverage, especially in low-resource settings, amplified health and economic burdens, highlighting the need for preparedness frameworks that combine speed with fairness. AREAS COVERED: We synthesize evidence from literature and policy reports regarding global vaccine roll-out, focusing on avertable mortality under alternative sharing scenarios, procurement design, pooled mechanisms such as COVAX, and the role of distributed manufacturing and delivery capacity. We also examine how transparent data-sharing, effective public communication, genomic surveillance, adaptive trial designs, and modeling hubs can support more responsive and equitable vaccine deployment. Across six reflection points, we translate these lessons into practical priorities for future pandemic readiness, including strengthening healthcare infrastructure, equitable procurement, data transparency, and safeguarding public health decision-making from political and commercial distortion. EXPERT OPINION: We argue that equity-by-design is essential if vaccine innovation is to deliver equitable public health impact. This requires geographically distributed manufacturing, transparency, equity-conditioned advance purchase agreements, and pre-agreed, epidemiology-triggered allocation of vaccines. We recommend institutionalizing disaggregated reporting, standardized data-sharing, greater pathogen genomic sequencing capacity, and communication strategies that support public health protection while countering misinformation.

Humans

Safety, humoral and cellular immune responses to a pre-pandemic adjuvanted influenza A (H5N8) vaccine.

Highly pathogenic avian influenza (HPAI) A(H5) viruses can be transmitted from infected birds to various mammalian species, including humans. Avian influenza viruses (AIVs), members of the Orthomyxoviridae family, possess segmented RNA genomes prone to reassortment, favoring the emergence of novel genetic traits that may alter transmissibility, pathogenicity, and antigenicity. Although no sustained human-to-human transmission has been reported, the potential adaptation of these viruses poses a significant pandemic threat. This study aimed to evaluate the non-clinical safety, toxicity, and humoral immune responses induced by an adjuvanted H5 influenza vaccine in rats and rabbits, to support future clinical safety trials in humans. Male and female Wistar rats and New Zealand rabbits were observed for 14, 28, and 90&#xa0;days after receiving two intramuscular doses of the H5N8 vaccine (15&#xa0;&#x3bc;g HA/dose) formulated with the IB160 oil-in-water emulsion adjuvant. No systemic comorbidities, central nervous system alterations, or relevant clinical signs were observed. Hematological parameters remained within normal ranges, with total and differential leukocyte counts showing only minor fluctuations (<1% of total leukocytes). Mild biochemical variations in urea and hepatic transaminase levels were not correlated with histopathological alterations. The vaccine elicited a robust humoral response soon after immunization, with all groups reaching protective HAI-antibody titers. Although antibody levels declined over time, particularly in males, they remained significantly above baseline, indicating durable immunological memory. Furthermore, the vaccine induced a specific cellular immune response, confirmed by IL-2 and TNF production by antigen-specific T lymphocytes in splenic cell cultures after the booster dose. In conclusion, the H5N8 vaccine with the IB160 adjuvant was well tolerated locally and systemically, without compromising vital organ function. The safety and immunogenicity findings are consistent with expectations for adjuvanted influenza vaccines, demonstrating strong and durable humoral and cellular immune responses.

H5N8 influenza vaccine

Transcriptomic and proteomic signatures following AS03-adjuvanted Influenza A/H7N9 vaccine.

INTRODUCTION: Vaccines targeting avian influenza virus A/H7N9 are poorly immunogenic. While the immune responses can be improved with oil-in-water emulsion adjuvants such as Adjuvant System 03 (AS03), the cellular mechanisms underpinning the adjuvant effect are incompletely characterized and poorly understood. METHODS: We enrolled 30 healthy adult participants and used RNA sequencing and quantitative proteomics to characterize the response to two doses of the influenza A/H7N9 vaccine, with and without AS03, in six immune cell types. These responses were compared to those seen after administration of an unadjuvanted seasonal in uenza A/H3N2 variant vaccine to identify signatures unique to adjuvanted influenza vaccines and correlated with later antibody responses. Transcriptomic and proteomic analyses revealed that. RESULTS: AS03-adjuvanted vaccine was associated with upregulation of immune pathways in innate immune cells within 24h following vaccination for phagocytosis, antigen presentation and processing, inflammasome activation, NK-cell mediated cytotoxicity, IgA production, and interferon-response pathways. Moreover, while major histocompatibility complex (MHC I and II) upregulation was observed across multiple immune cell types, MHCII gene transcription was also increased in the neutrophil compartment, generating the hypothesis that neutrophils may play a more important role in antigen presentation than previously understood. DISCUSSION: Taken together, these data provide a more complete mechanistic understanding of oil-in-water adjuvants and their role in enhancing the immune response for pandemic influenza preparedness. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/study/NCT02921997?term=NCT02921997&viewType, idientifier NCT02921997.

Adult

Global disparities in COVID-19 vaccine coverage associated with trajectories of SARS-CoV-2 adaptation.

BACKGROUND: Vaccination serves as an effective intervention for health promotion and disease prevention across the socioecological systems and has played an important role during the COVID-19 pandemic. However, global disparities in vaccine coverage have increased uncertainty about the trajectories of viral adaptation, and the potential interplay between SARS-CoV-2 adaptation and vaccine rollout warrants further quantification. METHODS: Using over 13&#xa0;million SARS-CoV-2 genomes across 86 countries from March 2020 to September 2022, we analyzed nonlinear associations between SARS-CoV-2 adaptation and vaccination coverage, considering public health and social measures, international travel, and infection dynamics, before and after the emergence of Omicron. Additionally, we examined the relationship between SARS-CoV-2 adaptation and COVID-19 mortality. RESULTS: During the pre-Omicron period, we found positive associations between nonsynonymous to synonymous divergence (dN/dS) ratios in the S1 subunit and medium levels of adjusted vaccine coverage (effect size: 0.96 [95% CI 0.47, 1.45]), while the association became insignificant at high levels (effect size: -1.89 [95% CI -4.20, 0.43]). However, no significant associations were found when Omicron dominated, possibly due to the immune escape ability of Omicron variants and the complex immune landscape shaped by mass hybrid immunity. Moreover, we observed evidence of dynamic interdependence and positive correlations between COVID-19 mortality and SARS-CoV-2 adaptation, with COVID-19 mortality interpreted as a proxy for uncontrolled viral spread. CONCLUSIONS: Our findings suggest a complex nonlinear relationship between vaccine-induced immunity and SARS-CoV-2 adaptation, with high vaccine coverage potentially linked to lower positive selection. We also observed directional coupling between COVID-19 mortality and SARS-CoV-2 adaptation. This may have implications for fair and fast vaccination in pandemic preparedness and response. CLINICAL TRIAL NUMBER: Not applicable.

Humans

Phylogeny and evolution of SARS-CoV-2 during Delta and Omicron variant waves in India.

SARS-CoV-2 evolution has continued to generate variants, responsible for new pandemic waves locally and globally. Varying disease presentation and severity has been ascribed to inherent variant characteristics and vaccine immunity. This study analyzed genomic data from 305 whole genome sequences from SARS-CoV-2 patients before and through the third wave in India. Delta variant was reported in patients without comorbidity (97%), while Omicron BA.2 was reported in patients with comorbidity (77%). Tissue adaptation studies brought forth higher propensity of Omicron variants to bronchial tissue than lung, contrary to observation in Delta variants from Delhi. Study of codon usage pattern distinguished the prevalent variants, clustering them separately, Omicron BA.2 isolated in February grouped away from December strains, and all BA.2 after December acquired a new mutation S959P in ORF1b (44.3% of BA.2 in the study) indicating ongoing evolution. Loss of critical spike mutations in Omicron BA.2 and gain of immune evasion mutations including G142D, reported in Delta but absent in BA.1, and S371F instead of S371L in BA.1 could explain very brief period of BA.1 in December 2021, followed by complete replacement by BA.2. Higher propensity of Omicron variants to bronchial tissue, probably ensured increased transmission while Omicron BA.2 became the prevalent variant possibly due to evolutionary trade-off. Virus evolution continues to shape the epidemic and its culmination.Communicated by Ramaswamy H. Sarma.

SARS-CoV-2

Efficient genome editing in Pseudomonas syringae pv. actinidiae using the CRISPR/FnCas12a system.

CRISPR-based gene editing has rarely been studied in plant pathogens. In this report, the CRISPR/FnCas12a system was successfully established for gene editing in Pseudomonas syringae pv. actinidiae (Psa), which causes bacterial canker (BC) of kiwifruit. The system was constructed in a Psa-suitable vector pBBR1-MCS2 to edit hopH1 or/and hopZ5, which encode effectors only present in Psa biovar 3 (Psa3) responsible for BC pandemic in kiwifruit worldwide. Two different CRISPR RNAs (crRNA) were designed to edit either hopH1 or/and hopZ5, and two different sets of PCR primers were used to screen deletions of the target genes and the presence of the vector in Psa. The deletion in Psa was impacted by the position of the DNAs targeted by the crRNAs. The vector-eliminated mutant could receive the editing system iteratively. Interestingly, the double mutant &#x394;hopZ5&#x394;hopH1 showed significantly stronger virulence than the wild-type Psa on Actinidia eriantha cv. White (resistant to BC), but weak virulence on A. chinensis cv. Hongyang (highly susceptible to BC), respectively, suggesting that hopH1 or/and hopZ5 potentially matches an unknown resistance gene in White. In summary, we have established the CRISPR/FnCas12a genome-editing system to probe gene function in the pathogen and to explore effector-target interactions in kiwifruit-Psa-pathosyetem.

Bacterial canker

Acute hemorrhagic conjunctivitis in Tunisia. Report of viral isolations.

Acute hemorrhagic conjunctivitis (AHC), a new disease entity first reported in 1969, has since become pandemic throughout the world. In Tunisia during an epidemic in 1972 to 1973 we studied 25 cases of AHC, which were characterized by explosive onset of lid edema, chemosis, conjunctival hemorrhages, follicular hypertrophy, and epithelial keratitis. Clinical signs peaked in 48 hours and cleared without sequelae in five to seven days. Paired acute- and convalescent-phase sera from six of the patients showed a rising titer of neutralizing antibody to the prototype strain of AHC virus (J6 70/71), which was isolated in Japan. Two viral isolates from Tunisian patients were also antigenically related to the Japanese strain, indicating that a single etiologic agent (a new member of the picornavirus group) is probably responsible for the current pandemic of AHC.

Antibodies, Viral

Methods for Cas13a expression and purification for use in CRISPR diagnostics.

The threat of emerging infectious diseases (e.g., SARS-CoV-2 the RNA virus responsible for the COVID-19 pandemic) has highlighted the importance of accurate and rapid testing for screening, patient diagnosis, and effective treatment of infectious disease. Nucleic acid diagnostic tools such as qPCR are considered the gold standard, providing a sensitive, accurate, and robust method of detection. However, these conventional diagnostic platforms are resource intensive, limited in some applications, and are almost always confined to laboratory settings. With the increasing demand for low-cost, rapid, and accurate point-of-care diagnostics, CRISPR-based systems have emerged as powerful tools to augment detection capabilities. Of note is the potent RNA detection enzyme, Leptotrichia buccalis (Lbu) Cas13a, which is capable of rapid RNA detection in complex mixtures with or without pre-amplification. To support its wide-spread use, we describe a detailed method for the expression, purification, and validation of LbuCas13a for use in molecular diagnostics.

SARS-CoV-2

Bacteriophages as vaccine platforms: Opportunities and challenges in translation.

Bacteriophages (phages) have recently received increased interest as versatile candidates for vaccine development. Their inherent characteristics, such as ease of genetic manipulation, high-density antigen display, intrinsic immunostimulatory properties, demonstrated human safety, and scalability in bacterial hosts, make them attractive as next-generation vaccine platforms. Additionally, their cost-effective production, stability, and existing regulatory approval for food and compassionate phage therapy provide a strong foundation for further development of phage-based vaccines. This commentary summarizes the types of phages, the strategies used, and current advances in phage-based vaccine development for viral and bacterial targets, and discusses the promises and challenges of this platform for novel vaccine development. Phage-based vaccines represent an innovative and promising platform for vaccine development to address significant medical and public health challenges, particularly in antimicrobial resistance, pandemic preparedness, and One Health. Accumulative experimental data have demonstrated that phage-based vaccines induce specific cellular, humoral, and mucosal immune responses at magnitudes comparable to those induced by other vaccine platforms. However, a better understanding of phage biology (interactions with the human immune system and microbiome), more carefully designed preclinical studies, Good Manufacturing Practice production development, the regulatory framework, and ultimately clinical trials are needed before the full potential of this platform is realized.

Animals

Prior vaccination prevents overactivation of innate immune responses during COVID-19 breakthrough infection.

At this stage in the COVID-19 pandemic, most infections are "breakthrough" infections that occur in individuals with prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure. To refine long-term vaccine strategies against emerging variants, we examined both innate and adaptive immunity in breakthrough infections. We performed single-cell transcriptomic, proteomic, and functional profiling of primary and breakthrough infections to compare immune responses from unvaccinated and vaccinated individuals during the SARS-CoV-2 Delta wave. Breakthrough infections were characterized by a less activated transcriptomic profile in monocytes and natural killer cells, with induction of pathways limiting monocyte migratory potential and natural killer cell proliferation. Furthermore, we observed a female-specific increase in transcriptomic and proteomic activation of multiple innate immune cell subsets during breakthrough infections. These insights suggest that prior SARS-CoV-2 vaccination prevents overactivation of innate immune responses during breakthrough infections with discernible sex-specific patterns and underscore the potential of harnessing vaccines in mitigating pathologic immune responses resulting from overactivation.

Immunity, Innate

Influenza: the vaccines.

The extreme antigenic lability of the influenza A viruses accounts for the less-than-ideal immune responses to them. With a possible swine flu pandemic in the offing, the "vaccine strategy" required is critical, particularly as the medical and public health communities in the United States embark on the first systematic attempt in history to blunt preemptively the impact of a pandemic.

Antigens, Viral

The return of measles: a dangerous comeback.

PURPOSE OF REVIEW: Measles has reemerged as a significant global public health threat, with increasing morbidity and mortality associated with declining vaccination rates. This review summarizes current global outbreaks, history of measles, vaccination and elimination status, vaccine hesitancy, and outbreak response and lessons learned highlighting different novel digital epidemiological tools. RECENT FINDINGS: Measles continues to surge worldwide with an estimated 11 million infections in 2024, which is more than prepandemic levels. Developing and developed countries are both facing measles outbreaks, with the United States at risk of losing measles elimination status. Recent studies have showed that worldwide percentages of two-dose measles vaccination were lower than 95% that is required to interrupt measles transmission in all WHO regions. Novel epidemiological tools such as interactive simulators, real-time use of dynamic models, serosurveillance, and others are transforming measles outbreak response and enable earlier outbreak detection, tracking, and targeted public health interventions. SUMMARY: Vaccine hesitancy is one of the top global health threats and developing a tailored evidence-based approach is necessary to establish and maintain measles elimination.

Humans

Multi-scale phylodynamic modelling of rapid punctuated pathogen evolution.

Computational multi-scale pandemic modelling remains a major and timely challenge. Here we identify specific requirements for a new class of models simulating pandemics across three scales: (1) pathogen evolution, often punctuated by the rapid emergence of new variants, (2) human interactions within a heterogeneous population, and (3) public health responses which constrain individual actions to control the disease transmission. We then present a pandemic modelling framework satisfying these requirements and capable of simulating feedback loops between dynamics unfolding at these different scales. The developed framework comprises a stochastic agent-based model of pandemic spread, coupled with a phylodynamic model that incorporates within-host pathogen evolution. It is validated with a case study, modelling the punctuated evolution of SARS-CoV-2, based on global and contemporary genomic surveillance data, which captures a large heterogeneous population. We demonstrate that the model replicates the essential features of the COVID-19 pandemic and virus evolution, while retaining computational tractability and scalability.

SARS-CoV-2

Integrative Multidimensional Profiling of Individuals Recovered from Mild COVID-19 Reveals Immune-Metabolic-Oxidative Network Interactions.

The COVID-19 pandemic underscored the need to better characterize immune and molecular responses following SARS-CoV-2 infection and vaccination. Beyond antibody and cellular immunity, COVID-19 involves oxidative stress and DNA damage, affecting repair mechanisms and metabolic adaptation linked to immune resilience. Here, we present a multidimensional analysis of 20 individuals who recovered from mild COVID-19, integrating clinical features with humoral and cellular immune responses, T cell and myeloid phenotypes, oxidative stress, DNA damage, and metabolomic and lipidomic profiles. Although most individual parameters fell within physiological ranges, network modeling revealed structured associations spanning multiple biological domains. A central finding was a coherent cluster organized around vaccine dose number, linking anti-Spike antibody titers, oxidative stress, bioenergetic signatures, and granulocyte activation. Higher vaccination was associated with stronger humoral responses, lower oxidative stress, and a more balanced myeloid-metabolic profile, suggesting a potential protective role extending beyond antibody induction. Additional associations linked symptom patterns to T cell differentiation states, anti-nucleocapsid responses to systemic inflammation, and anaerobic signatures to DNA damage markers, revealing interconnections between immunometabolism, clinical expression, and genomic stress. Despite the small sample size, these findings offer a preliminary systems-level perspective on mild COVID-19 recovery and illustrate the value of integrative exploratory frameworks in infectious disease research, laying the groundwork for validation in larger longitudinal cohorts.

Humans

Syndemics, violence and injury: exploring historical relationships between infectious disease epidemics and violent crime in South Africa.

This paper explores historical and contemporary intersections between mass-mortality epidemics and violent crime in South Africa, focusing on four major epidemics - Spanish Flu, tuberculosis, HIV, and Covid-19. The study integrates epidemiological data and contextual historical information such as crime statistics, archival records, and secondary scholarship to explore whether epidemic-driven mortality crises are associated with subsequent changes in violence and injury profiles. With the possible exception of gendered violence, the study finds little evidence that earlier epidemics directly contributed to rapid or sustained increases in violent crime, despite causing substantial adult mortality and long-term social and economic disruption. A comparison between epidemic and socio-economic profiles strongly suggests that the significant increases in violent crime recorded after the Covid-19 pandemic are highly localised, and may be more strongly related to lockdown responses, including alcohol restrictions, rather than the effects of disease itself.

Humans