Dengue virus (DENV) is a mosquito-borne flavivirus with four distinct serotypes (DENV-1 to DENV-4) and is endemic in tropical and subtropical regions worldwide. It can cause a range of illnesses, from self-resolving dengue fever to severe dengue hemorrhagic fever or dengue shock syndrome. Dengue fever is a major public health hazard in tropical and subtropical areas. Advances in treatment and prevention have mainly focused on developing vaccines and antiviral medications. Currently, no treatment for dengue fever works for everyone. While some antiviral candidates are in clinical trials, most remain in preclinical or early research stages. Regarding vaccinations, the WHO has approved or prequalified two live-attenuated options: TAK-003 (Qdenga®) and Dengvaxia® (CYD-TDV). However, both vaccines have drawbacks, including limited effectiveness across serotypes and safety issues in seronegative individuals. Current research aims to elucidate the complex host immune responses that underlie dengue pathogenesis and vaccine-induced protection, to develop more effective treatments and preventive measures. Critically, most approaches remain at the experimental or preclinical stage and require further clinical evaluation.

We report six lactose-fermenting Salmonella Strathcona isolates carrying a lac operon on an IncHI2/IncHI2A plasmid. Whole-genome sequencing revealed intact lacI-lacZ-lacY and truncated lacA genes. These isolates represent the first detection of lactose-fermenting S. Strathcona, highlighting a risk of diagnostic errors due to reliance on lactose fermentation-based phenotypic identification.

The emergence of the SARS-CoV-2 Omicron variant led to Pakistan's Omicron wave from December 2021 to March 2022. This study investigated the molecular epidemiology of the early Omicron wave in Pakistan through genomic surveillance and travel history-informed Bayesian phylogeographic inference. PCR-based genotyping and whole-genome sequencing shows a shift from the BA.1 lineage's early replacement of Delta as Pakistan's dominant lineage in December 2021, until it was replaced by BA.2 predominance by March 2022. We identify rare spike protein mutations and the absence of key mutations in circulating strains. In order to determine the earliest drivers of the BA.1 wave in Pakistan we performed Bayesian phylogeographic analysis which reveals multiple introductions of BA.1 into Pakistan, primarily from Northern Europe. Our findings highlight the importance of continued genomic surveillance, particularly at points of entry, and the need to address global disparities in sequencing capacity to better understand and control the spread of SARS-CoV-2 variants.

A total of 294 pooled samples from ten species were tested for the presence of Megalocytivirus pagrus 1 in a two-year survey. Among them, Megalocytivirus pagrus 1 was detected from 36 samples (pool prevalence of 12.24%) by PCR assay targeting the major capsid protein (MCP) gene. The MCP gene from five representative positives was sequenced. Pairwise identity and maximum-likelihood phylogenetic analyses based on MCP nucleotide sequences indicated close genetic relatedness between the five sequences obtained in this study and ISKNV Clade 1 reference sequences; four sequences exhibited ≥99.68% nucleotide identity to Clade 1 strains, whereas one displayed comparatively lower identity, but was still placed close to the ISKNV Clade 1-associated assemblage. These findings support the use of the MCP gene as a primary marker for distinguishing Megalocytivirus pagrus 1 genotype and clades; however, because the MCP gene constitutes less than 2% of the viral genome, additional loci (e.g., ATPase) or whole-genome sequencing are recommended for higher-resolution phylogenetic analysis. Taken together with additional metadata (host and reported origin), the MCP sequence provides a reference dataset for comparative analysis of Megalocytivirus pagrus 1 diversity. And as the findings here are based on gene sequence, it indicates genetic relatedness rather than a definite diagnosis of an infectious virus. The sequences are available in GenBank, and international cross-study comparison would support future scientific evaluation of the genus Megalocytivirus, in alignment with the World Organisation for Animal Health criteria.

The recent serological detection of Coxiella burnetii exposure in Somali livestock (12.6% seroprevalence among 372 ruminants) is an important addition to the limited epidemiological evidence on zoonotic disease ecology in the Horn of Africa. This finding, combined with prior molecular evidence of a novel C. burnetii genotype (D21) in ticks infesting Somali camels and high seroprevalence (21.4%) in febrile patients in neighboring Ethiopia, provides a rationale for investigating Q fever as a potentially under-recognized zoonosis in the region. However, critical knowledge gaps persist, including limited geographic sampling, absence of published human serosurveillance from Somalia, lack of molecular characterization of circulating strains in livestock, and inadequate understanding of transmission dynamics at the human-animal-environment interface. This correspondence synthesizes available evidence, identifies specific research priorities, and proposes a context-adapted One Health surveillance framework as a conceptual proposal requiring feasibility assessment and stakeholder adaptation. We argue that the serological evidence of C. burnetii exposure in Somali ruminants should catalyze coordinated, cross-sectoral interventions feasible within Somalia's current resource-limited setting.

The malaria hypothesis proposes that in areas with a high incidence of malaria transmission, there is likely to be a high prevalence of genetic variants that confer protection against the disease. These resistance variants, located at different loci, may be statistically associated, leading to a non-random alteration in allele frequencies and exhibiting fitness levels that are not independent across loci (epistatic interaction). The aim of this study was to investigate whether signatures of epistatic selection exist between the Duffy and G6PD loci and to estimate the adaptive values associated with their genotype combinations in the population of Buenaventura, a malaria-endemic region of the Colombian Pacific. To achieve this, the indices DST[2], DIS[2], D'IS[2], and D'ST[2] were calculated to partition the variance of linkage disequilibrium (LD) between pairs of loci, using the OhtaDstats package in R software. Additionally, fitness values and selection coefficients were estimated for the genotypic combinations of these variants. To our knowledge, this study provides the first evidence of epistatic selection between the Duffy and G6PD loci in a malaria-endemic population from the Colombian Pacific, an interaction not previously reported in the literature using a linkage disequilibrium-based approach. This finding is supported by the calculated indices, as well as by the higher fitness values observed in genotype combinations involving these resistance variants. The observed interaction may reflect complementary protection against different Plasmodium species and the absence of physiological antagonism between the two resistance mechanisms.

Peste des petits ruminants (PPR) is a highly contagious viral disease of small ruminants caused by the peste des petits ruminants virus (PPRV), which is classified into four distinct genetic lineages (I-IV). A critical concern is the rapid and widespread expansion of lineage IV (LIV) across West Africa over the past decade. In this study, we generated full or partial genome sequence from 26 new PPRV samples, including historical (pre-2000) and recent African LIV isolates, offering the first opportunity to investigate the evolutionary history of LIV in Africa and identify genetic events potentially associated with its recent spread. These new sequences were aligned with 141 publicly available PPRV sequences to perform phylogenomic analyses. Results reveal that the most ancestral LIV group comprises strains circulating in Sub-Saharan Africa (designated clade LIVssa), providing new evidence for an African origin of lineage IV. Our results further indicate that PPRV strains linked to the recent West African expansion of LIV belong to a specific LIVssa subclade, termed NigB. We identified multiple signatures of selection pressure within the LIVssa sublineage, particularly in the NigB subclade. Several amino acid substitutions unique to LIVssa or NigB were detected, some of which may impact protein function and warrant prioritised investigation. While additional genomic data are required to confirm the association between the NigB subclade and the ongoing spread of LIV in West Africa, this expansion is alarming and demands intensified research efforts using integrative approaches. The evolutionary adaptations observed in LIVssa could undermine current disease control strategies in regions where PPR poses significant threats to food security and local economies.

Biofilms are structured microbial communities embedded within a self-produced extracellular polymeric substance matrix that promotes persistence under adverse environmental and host-associated conditions. Their clinical importance is primarily associated with increased antimicrobial tolerance, evasion of host immune responses, and persistence in chronic and medical device-associated infections. This review provides an integrated overview of the molecular and genetic determinants governing biofilm development, including surface attachment, matrix biosynthesis, quorum-sensing networks, cyclic-di-GMP signaling, maturation, and dispersal. The contribution of key matrix components, including polysaccharides, extracellular proteins, extracellular DNA, lipids, and water, is considered in relation to biofilm architecture, stability, and cellular adaptation. Clinically relevant biofilm-forming microorganisms, including Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Candida albicans, are major contributors to chronic infections, healthcare-associated infections, and infections associated with medical devices. The mechanisms contributing to reduced antimicrobial susceptibility in biofilms include restricted drug penetration, metabolic heterogeneity, persister-cell formation, efflux activity, stress-response pathways, and horizontal gene transfer. Conventional in vitro and in vivo biofilm models often fail to fully mimic the complex conditions present within the human host, thereby limiting the clinical translation and therapeutic relevance of experimental findings. In addition, emerging antibiofilm interventions, including quorum-sensing inhibitors, matrix-degrading enzymes, nanoparticle-based delivery systems, antimicrobial peptides, and bacteriophage therapy, are considered alongside the growing application of multi-omics and artificial intelligence for biomarker discovery and therapeutic target identification.

Phlebotomine sand flies are important vectors of various pathogens, including the Chandipura virus (CHPV), a neurotropic rhabdovirus associated with fatal pediatric encephalitis outbreaks in India. Gujarat, a CHPV-endemic region, lacks comprehensive molecular data on sand fly species. Accurate species identification is important for effective vector surveillance and control strategies. 2950 sand flies were collected from 14 districts using aspirators and traps. Morphological identification was performed by using standard taxonomic keys. DNA barcoding of the mitochondrial cytochrome c oxidase subunit I (COI) gene was performed using universal barcoding primers. Sequence alignment, phylogenetic analysis, and genetic divergence calculations were performed through MEGA and BOLD Systems databases. Seven species were identified: Sergentomyia babu, Se. punjabensis, Se. insularis, Se. bailyi, Se. shorttii, Phlebotomus argentipes, and Ph. papatasi. Phylogenetic clustering showed strong bootstrap support (>90%), confirming congruence between morphological and molecular identification. Intraspecific divergence was low (0.5 to 2.0%), while interspecific divergence was comparatively higher (5.4 to 18.9%), indicating a clear "barcode gap" that validated species boundaries. COI DNA barcoding reliably distinguished sand fly species from CHPV-endemic Gujarat. The study highlights the presence of epidemiologically relevant vectors, supports the use of molecular taxonomy in entomological surveillance, and emphasizes the need to expand DNA barcode reference libraries for Indian sand flies.