Infection, Genetics and Evolution
○ Elsevier BV
Preprints posted in the last 30 days, ranked by how well they match Infection, Genetics and Evolution's content profile, based on 42 papers previously published here. The average preprint has a 0.03% match score for this journal, so anything above that is already an above-average fit.
Espinosa-Parrilla, Y.; Fuentes-Guajardo, M.; Carvajal-Silva, L.; Aguilar-Valdes, K.; Signore, I. A.; Arevalo, T. V.; Zapata-Contreras, D.; Donoso, G.; Zuniga-Pacheco, P.; Valenzuela-Jorquera, H.; Rosso Villanelo, S. A.; Tobar-Calfucoy, E. A.; Yanez, C. E.; Carvajal, F.; Saez Hidalgo, J. M.; Sanhueza, S.; Quiroga, R. A.; Martinez, M. F.; Cerpa, L. C.; Varela, N. M.; Cappelli, C. L.; Campillay-Veliz, C. P.; Valdebenito-Maturana, B.; Garcia-Araya, J.; Santander, R. A.; Opazo, J.; Retamales-Ortega, R.; Bocchieri, P.; Alarcon, T. A.; Plaza, A.; Moraga, M.; Munoz, C. A.; Echeverria, C. A.; Dorador,
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Background: More than five years after the COVID-19 outbreak, the infection by the SARS-CoV-2 virus should still be considered as a global threat with highly heterogeneous clinical outcomes from asymptomatic to fatal depending on existing genetic and phenotypic inter-individual and inter-population variability. Our objective is to identify risk loci associated with COVID-19 in an admixed Latin American population. Methods: We performed a genome-wide association study in the framework of the Chilean C19-GenoNet team, analyzing a cohort of 3,417 individuals recruited from the northernmost to the southernmost regions of the country, who presented variations in the severity of their COVID-19 clinical manifestations. Results: Our investigation replicated the extensively reported association of several variants at the 3p21.31 locus with COVID-19 severity and found a suggestive association for a variant within the FOXP4 gene at 6p21.1 with COVID-19 hospitalization. Both associations appear to be shared with other populations. Importantly, our study identified three previously unreported loci associated with COVID-19 severity or hospitalization at 7q21.11, 16p13.12 and 6p25.3, and one additional locus at 4p13 associated with SARS-CoV-2 positivity, a proxy for infection susceptibility. Conclusions: these new risk loci may represent population-specific effects in Chilean and, potentially, other Latin American admixed groups. Our study highlights the importance of expanding efforts to study underrepresented and genetically different populations, which may provide new clues on the genetic basis of human diseases and may help to anticipate global responses to emerging viral infections and future pandemics.
Rahman, T.; Khan, T.; Haider, A.; Moon, S. B.; Samia, N. S. N.; Mah-E-Muneer, S.; Mamun, G. M. S.; Chowdhury, F.; Rahman, M.; Jubair, M.
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Morganella morganii is an opportunistic pathogen with intrinsic and acquired antimicrobial resistance, but its genomic epidemiology remains poorly characterized in Bangladesh. We sequenced and compared genomes of 47 stool-derived M. morganii isolates from hospital (n = 29) and community (n = 18) participants in urban Dhaka. Susceptibility testing showed frequent resistance to imipenem (70.2%) and cefuroxime (97.9%), while all isolates were resistant to colistin. Resistance to meropenem (6.4%) and ertapenem (2.1%) was uncommon. Based on acquired non-susceptibility across tested antimicrobial categories, 18/47 (38.3%) isolates were multidrug-resistant, including 15/29 (51.7%) hospital-derived and 3/18 (16.7%) community-derived isolates. Genomic analysis identified 17 {beta}-lactamase alleles including Morganella-associated chromosomal {beta}-lactamases and acquired resistance determinants, with blaOXA-1, blaDHA-21, blaCTX-M-15, and blaTEM-1 predominating. However, no recognized acquired carbapenemase genes were detected. Among 44 non-{beta}-lactam resistance genes, tetB was most frequent. Phylogenomic and average nucleotide identity analyses classified 31 isolates as M. morganii subsp. morganii and 16 as the subsp. intermedius lineage. Considerable population diversity was observed, with 33 distinct sequence types among the 47 isolates and no clear clustering by hospital or community origin. The subsp. intermedius isolates showed greater genomic heterogeneity than subsp. morganii, with a minimum within-group average nucleotide identity of 94.2%. Single nucleotide variant (SNV) analysis identified several closely related isolate groups, including an ST1 pair differing by 10 SNVs and collected three days apart within the same hospital, although direct transmission could not be established. Virulence-associated gene profiles differed between subspecies, with hemolysin- and toxin-associated genes predominantly detected among subsp. morganii isolates and largely absent from subsp. intermedius. Overall, these findings reveal substantial genomic diversity, a considerable burden of multidrug resistance, and subspecies-associated differences in virulence gene content among M. morganii circulating in Dhaka, while the frequent imipenem-non-susceptible but carbapenemase-negative phenotype highlights the need to investigate alternative carbapenem resistance mechanisms.
Banerjee, I.; Prakash, A.; Nelson, E. J. R.
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Cytosolic phospholipase A2 (cPLA2), encoded by PLA2G4A plays a crucial role in platelet activation through thromboxane A2 biosynthesis. Defects in this pathway can lead to bleeding disorders; however, the precise role of cPLA2 in Glanzmann thrombasthenia (GT) or GT-like syndromes remains poorly understood. The current study emerged from a fortuitous discovery of novel PLA2G4A variants, p.Asp455Val (D455V) and p.Glu119Lys (E119K), among 3 GT patients from two unrelated families in south India. We envisaged a hypothesis to identify a hitherto unknown role of cPLA2 that could be attributed to GT-like bleeding symptoms in these patients. An extensive computational workflow, including variant classification, conservation analysis, stability prediction, molecular docking, molecular dynamics simulations, principal component analysis, and binding free energy (MMPBSA) calculations, were employed to assess mutation-induced alterations in the cPLA2 protein. The current findings depicted that both variants affected conformational dynamics, ligand recognition patterns, and local interaction networks, without causing any drastic global structural destabilization. In particular, the D455V partially disrupted the catalytic domain, potentially reducing substrate (PAPC) stabilization and hampering interactions with catalytic products. Likewise, the E119K variant partially affected the C2 domain, potentially altered electrostatic interactions and enhanced regional flexibility, which may compromise product (AA) stabilization. Further analyses revealed mutation-induced changes in collective motions, protein-ligand interactions, solvent accessibility, and secondary structural elements. Overall, our findings promote the hypothesis that both E119K and D455V variants may partially alter phospholipid-associated interactions, and cPLA2-mediated downstream signaling. Moreover, this study underscores cPLA2 as a potential modifier of platelet function and bleeding severity.
Ferrandez Verdu, T.; Ruiz, F. P.; Carrillo Lopez, A. F.; Tapia Caro, M.; Castillo Gonzalez, A.; Vives Lopez, R.; Amoros Box, C.; Marcos Perez, M.; Boratynski, Z.; Pavlickova, B.
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The fieldwork was carried out between December 2023 and June 2025, with the aim, among others, of confirming the possible presence of the North African Gerbil (Gerbillus campestris) in Melilla. To this end, 56 camera trap stations were installed, each equipped with a camera trap. Of the total number of camera trap stations installed, the presence of Gerbillus campestris was detected in six of them, representing a capture success rate of 10.71%. Following the detection of the species, a specimen was captured using cage traps. For identification purposes, samples of epithelial tissue from the ear and faeces were collected. These samples were sent to the Institute of Vertebrate Biology of the Czech Academy of Sciences, Brno, Czech Republic, for analysis. There, DNA was extracted from the samples using the Innu PREP DNA Mini Kit 2.0 (IST Innuscreen GmbH, Germany) according to the manufacturer's protocol. The results obtained confirm, for the first time through records of the species, the presence of Gerbillus campestris in Melilla and, therefore, in Spain and Europe.
da Silva, G.; Tapaopong, P.; Holzschuh, A.; Sattabongkot, J.; Nguitragool, W.; Koepfli, C.
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Population genomic studies have revealed strong regional structure in Plasmodium knowlesi across Southeast Asia. To facilitate routine genomic surveillance, we developed a targeted amplicon sequencing panel that preserves the large- and small-scale population genetic structure. We screened published genomes for short, highly polymorphic targets and a 30-SNP barcode. We validated multiplexed amplification and sequencing using a portable Oxford Nanopore Technologies MinION sequencer on 28 clinical infections from four southern Thai provinces collected between 2018-2023. Twenty-seven loci yielded sequence data and 23 infections with data from at least eight loci were retained for analysis. Across the 23 Thai infections and 104 published Malaysian genomes, 586 diverse SNPs were observed. The amplicon panel and 30-SNP barcode retained the major population structure observed in genome-wide data, including a clear distinction between Bornean and Peninsular Malaysian infections and two clusters in Borneo. Across newly sequenced Thai infections, 25 loci were diverse and showed substantial diversity (mean expected heterozygosity = 0.69). All infections were effectively monoclonal. Pairwise identity-by-descent revealed substantial recent relatedness, with 46 of 253 pairs at or above 0.5. Two Thai genetic groups (n = 12 and n = 11) were observed, mirroring previously observed structure in peninsular Malaysia. Groups were not significantly associated with province or collection year. In conclusion, targeted sequencing can reveal geographically informative population structure across scales and thus support surveillance.
Garcia-Gonzalez, E.; Sempere, J.; Llamosi, M.; Perez-Garcia, C.; Ubeda, A.; Sanchez-Honrado, A.; Agullo, L.; Ardanuy, C.; Perez-Fernandez, L.; Ocampo-Sosa, A.; Ramos-Sevillano, E.; Brown, J. S.; Domenech, M.; Yuste, J.
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Objectives: To evaluate the epidemiological evolution of unique pneumococcal serotypes covered by either PCV20 or PCV21, common serotypes by both vaccines and non-vaccine serotypes in adults. Methods: We characterized all national IPD clinical isolates from January 2009 to June 2026. Results: The highest burden of IPD was caused by serotypes shared between PCV20 and PCV21 with serotypes 3 and 8 the most prevalent in adults of all ages. During the pre-pandemic period, IPD caused by unique-PCV20 serotypes declined probably due to herd protection by paediatric vaccination with PCVs. In contrast, unique-PCV21 serotypes increased in incidence accounting for more cases than unique-PCV20 serotypes. However, after the COVID-19 pandemic, a different pattern was observed with unique-PCV20 serotypes increasing in incidence due a marked rise in IPD caused by serotypes 4 and 14 that has progressively reduced the gap in disease coverage. In adults aged 18-64 years, the fraction of disease that could be prevented with PCV20/PCV21 changed from 5% in favour of PCV21 (years 2022/2023) to 15% in favour of PCV20 (year 2026) whereas in adults [≥]65 years the vaccine contribution declined from 20% in favour of PCV21 (year 2022) to 8% in 2026. Conclusions: IPD trends in adults have changed after the COVID-19 pandemic, especially in recent years. Our study emphasizes the rapid re-emergence of infections caused by traditional PCV7 serotypes especially serotypes 4 and 14 and reinforce the idea that the use of broader PCVs must be accompanied by an increase in the uptake rates in adults of all ages.
DE MEEUS, T.; Ravel, S.; Kagbadouno, M.; BERTE, D.; SEGARD, A.; LEPAIS, O.
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Tsetse flies are strictly found is sub-Saharan Africa where they are responsible for the transmission and maintenance of African trypanosomiases in humans (HAT) and animals (AAT). Vector control has been recognized as an essential tool to fight against these diseases. Nevertheless, it requires the best possible knowledge of the biology of the targeted population. Population genetics tools can prove very useful to obtain such information but require the use of polymorphic and reliable genetic markers. In this paper we present the development of microsatellite markers using a new high-throughput sequencing based technology (SSRseq). We applied it on two species of tsetse flies from three HAT foci and obtained more accurate results as compared to microsatellite loci developed with classic methods. We could indeed use 9 to 14 SSRseq loci without the several problems generally met with classic microsatellites, as all were located in autosomes, without short allele dominance or stuttering and very few null alleles. SSRseq loci appeared much more polymorphic in tsetse flies as compared to other species (fungi, trees, bees, or fishes), which suggested much higher effective population sizes, much higher mutation rates of the genome or both, suggesting high capacities for evolutionary adaptation. With the 9-14 loci kept, we confirmed the propensity of these flies to move almost freely in the whole zones investigated, and also highlighted the possible evolutionary response of one of the unkept loci regarding vector control devices used in these HAT foci, which will require further studies. We suggest for further population structure studies to use only loci with less than 1% missing data, which proved being a good and fast selection strategy to get the most reliable results.
Khan Chowdhury, A. R.; Islam, S.; Farid, A.; Lamia, F.; Ahmad, T. F.; Hossain, N. J.; Paul, A. R.; Afrin, T.; Elias, S. M.
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Drug targets and vaccines for bacterial diseases are challenging to develop. Computational subtractive genomics and reverse vaccinology offer a viable substitute for conventional drug and vaccine development approaches. In recent years, Pasteurella multocida, a Gram-negative pathogen responsible for severe infections in humans along with major diseases in livestock and poultry, has developed resistance to multiple drugs. As a result, there is an urgent demand for research into reliable, efficient, highly potent, and cost-effective strategies to combat the rise of Pasteurella multocida infections. To address this, the present study integrated an in silico subtractive genomics and reverse vaccinology workflow to pinpoint proteins with potential value as both drug and vaccine targets. From the complete Pasteurella multocida Pm70 proteome, we identified 446 proteins that had no similarities with human proteins, out of which 129 were found to be essential for the pathogens survival. These 129 proteins are therefore potential candidates for drug development. Further metabolic pathway analysis, virulence potential, subcellular localization, and structural analyses revealed two outer membrane proteins, namely, 47 kDa outer membrane protein and lipopolysaccharide-assembly protein LptD, as promising candidates for therapeutic development. Subsequent antigenicity analysis revealed both outer membrane proteins as potential vaccine targets, exhibiting highly favorable antigenicity scores. Candidate B- and T-cell epitopes were systematically mapped from these two targets based on antigenicity, immunogenicity, toxicity, and allergenicity potential and only high-confidence epitopes were assembled using adjuvants and class-specific linkers to construct the final multi-epitope vaccine (MEV). The designed MEV construct was demonstrated to be highly antigenic, non-toxic and non-allergenic to humans, while possessing favorable structural and physicochemical properties, and exhibited strong binding interactions with human toll-like receptors with minimal molecular deformability. Although further experimental validation is recommended to fully assess their efficacy, the present study establishes a solid foundation for the development of novel therapeutics and vaccine candidates against P. multocida, ultimately contributing to the reduction of its rising infections.
Asanabe, H.; Murakami, S.; Dobata, S.
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Aim To investigate how repeated historical connections between continental islands and the mainland have shaped the phylogeographic structure and genetic diversity of populations, using the widespread water strider Aquarius paludum as a model. Location Japan Taxon Water strider Aquarius paludum (Insecta: Hemiptera: Gerridae) Methods We analysed mitochondrial (COI and COII) and nuclear (ITS1) DNA sequences from populations across the Japanese archipelago and the Eurasian continent. Phylogenetic and population genetic analyses were used to reconstruct phylogeographic structure and infer demographic history. Results Western Japanese populations exhibited nucleotide diversity comparable to that of continental populations despite their insular distribution. Bayesian phylogenetic analyses identified two major mitochondrial haplogroups (A and B) that frequently co-occurred across the Japanese archipelago. Haplogroup A, which is rare on the Eurasian continent, occurred at high frequency in Japan and showed pronounced isolation by distance, whereas haplogroup B showed only weak but significant isolation by distance and was significantly more frequent in populations closer to the coast. These contrasting spatial patterns within species indicate distinct demographic histories for the two mitochondrial lineages. Main conclusion Repeated colonization from the Eurasian continent and the long-term coexistence of mitochondrial lineages with different demographic histories have shaped the pattern of genetic diversity of A. paludum in the Japanese archipelago. Our findings exemplify how continental islands can accumulate genetic diversity through lineage accumulation and secondary contact, which produces an intraspecific phylogeographic pattern comparable to those observed during an early phase of the taxon cycle between species.
Mastretta-Yanes, A.; Arredondo Amezcua, L.; Llanes-Quevedo, A.; Latorre-Cardenas, M. C.; Ornelas, J. F.; Ramirez Barahona, S.; Zarza, E.; Amaro-Garcia, R.; Acevedo Gasman, F.; Alavez, V.; Burgeff, C.; Cruz-Angon, A.; Contreras-Diaz, R. G.; Orjuela Restrepo, M. A.; Oliveros-Galindo, O.; Rios-Lopez, M.; Rivera-Rodriguez, D. M.; Sanchez-Gonzalez, J. d. J.; Suarez-Acuna, S.; da Silva, J. M.; Hoban, S.; Koppa, V.; Laikre, L.; Wegier, A.
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Megadiverse countries concentrate most of the World's biodiversity. These countries encompass different levels of research infrastructure, and nearly all of them have been historically committed to the Convention of Biological Diversity, often setting precedents and leading new approaches. Here, we ask whether the assessment of genetic diversity indicators provide novel insights for biodiversity management and conservation in one of those countries, Mexico. We evaluated the first national application of the Kunming-Montreal Global Biodiversity Framework (GBF), genetic diversity indicators in Mexico. The data covered 97 taxa across diverse ecosystem types and taxonomic groups, including crop wild relatives, to assess the capacity of genetic diversity indicators to provide novel insights, as well as their relevance for strengthening national conservation strategies. We calculated two indicators: the proportion of populations with an effective population size greater than 500 (Ne 500) and the proportion of populations maintained (PM). Data were sufficient to estimate the Ne 500 indicator for 47 taxa and the PM for 28 taxa, with mean indicator values of 0.217 and 0.936, respectively. Species' geographic range was positively associated with Ne 500, whereas national endemicity had no significant effect. Comparisons with the IUCN Red List and Mexico's national extinction-risk legislation revealed that genetic vulnerability occurs even among taxa not currently recognized as threatened. Our findings highlight a gap in legal recognition of genetic diversity protection that could be strengthened by incorporating population-level assessments focused on maintaining adaptive potential in the long-term. Additionally, the indicators allowed to highlight conservation concerns within crop wild relatives, though fully realizing their potential requires integrating the entire wild-to-domesticated complex. The Mexican experience highlights that the main challenge for scaling the monitoring of genetic diversity is not only generating new data, but integrating existing information into systems that strengthen collaboration and communication among researchers, local communities, and government institutions.
van Vliet, A. H. M.
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Introduction. Histoplasma capsulatum is an important fungal pathogen of humans, especially in immunocompromised patients, and the World Health Organisation has listed Histoplasma as a High Priority fungal pathogen. The taxonomy of the genus Histoplasma is still under development, but its only species H. capsulatum has at least of seven lineages, and a range of sublineages. Gap Statement. Allelic multilocus sequence typing (MLST) has been very successfully applied for typing and epidemiology of pathogenic bacteria, but its adoption for fungal pathogens is more limited. Genome sequence-based MLST approaches promise much a higher resolution for comparative phylogenetics, but there are only a small number of genome assemblies available for H. capsulatum. Aim. To develop and validate genome-based MLST typing for H. capsulatum. Methodology. A total of 406 genome assemblies were generated from publicly available Illumina short-read sequencing samples. Selected genome assemblies were subsequently used to generate MLST schemes with chewBBACA, based on whole genome sequences (wgMLST), NCBI-obtained annotations (annMLST) and annotations obtained with Funannotate (fanMLST), and used for lineage identification, and comparative analyses of population structure. Results. Genome assemblies were successfully generated for 406 H. capsulatum samples, with BUSCO completeness scores of over 98%. A subset of 60 genome assemblies was used to generate and validate MLST schemes based on the 60 genome assemblies, 5 genome annotations obtained from Genbank, and 13 genome annotations generated using Funannotate, resulting in schemes with > 8,000 markers. Each of the MLST schemes allowed reproducible separation of all 7 lineages and 6 H. capsulatum Suramericanum sublineages, without the need for high-performance clusters or powerful computing equipment. Comparison of the different schemes using tanglegrams and scatter plots showed good reproducibility (r2 values of 0.8-1.0). Comparison of total sizes of genome assemblies showed significant lineage-dependent size differences, with the Suramericanum, LAmB, India, Capsulatum and Mississippiense lineages averaging a total genome size of 30-33 million bp, and the Africa and Ohiense lineages averaging at 39 million bp. Conclusion. Genome sequence- and especially genome annotation-based MLST analyses are a promising approach that can be adapted as a rapid, high-throughput method for genomic clustering and epidemiological tracing of pathogenic fungi.
Ito, T.; Hayakawa, T.; Kurihara, Y.; Hanya, G.; Kaneko, A.; Natsume, T.; Aisu, S.; Honda, T.; Wakamori, H.; Yachimori, S.; Anezaki, T.; Omi, T.; Hayama, S.-i.; Kawamoto, Y.
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The relative roles of genetic drift, inbreeding, and natural selection in island evolution have been fundamental themes in evolutionary biology for nearly a century. However, empirical studies have yet to reach a consensus, and research integrating both genotypes and phenotypes in primates remains limited. The present study aims to estimate the demographic history of an island primate population, the Yakushima macaque (Macaca fuscata yakui), and evaluate the genomic and morphological consequences of its isolation. To this end, we conducted population genetic analyses based on whole-genome sequencing and geometric morphometric analyses of cranial shape. Our results indicate that M. f. yakui has been isolated with an effective population size of several thousand individuals for over 100,000 years. Although we detected signatures of purifying selection, deleterious alleles have not been sufficiently purged. The degree of fluctuating asymmetry in males was slightly, yet significantly, higher in M. f. yakui than in mainland populations, whereas this trend was not observed in females. Marginal evidence of directional selection was found for cranial size, but not for shape. Overall, our findings suggest that due to long-term isolation, genetic drift and inbreeding have exerted a substantial influence on shaping genotypic and phenotypic variation in this island population.
Singh, K. R.; Anuradha, D. C. M.; Suresh kumar, D. C.
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This study aims to identify potential inhibitors of the Ag85C enzyme from Mycobacterium tuberculosis through primary docking, pharmacophore modelling, and ADME/pharmacokinetics analysis. Delamanid and Pretomanid emerged as the top hits in primary docking, demonstrating strong binding affinities and interactions with key active site residues. A robust pharmacophore model was developed, identifying essential features for binding and used to screen 4254 antituberculotic compounds, yielding three promising candidates: F0314-0040, F0398-0505, and F0349-2716. These compounds exhibited high binding affinities in major docking studies. ADME and pharmacokinetics analysis revealed favorable Drug likeness and absorption profiles, supporting their potential as effective antituberculotic agents. The integration of computational methods provided a comprehensive approach for rational drug design.
Correa, L.; Dezordi, F.; da Silva, A. c.; Melo, J.; Dias, Y.; Resende, P. C.; Appolinario, L.; Siqueira, M.; Ogrzewalska, M.; Wallau, G. d. L.
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Bats are major natural reservoirs for coronaviruses, yet complete viral genomes from South America remain scarce, limiting evolutionary and taxonomic understanding. Here, we conducted metatranscriptomic sequencing of coronavirus-positive bat samples collected across two ecologically distinct Brazilian biomes: the Atlantic Forest and the semi-arid Caatinga. We recovered seven complete or near-complete genomes belonging to Alphacoronavirus and Betacoronavirus. Phylogenetic and comparative similarity analyses of conserved replicase domains (3CLpro, NiRAN, RdRp, ZBD, HEL1), following International Committee on Taxonomy of Viruses (ICTV) demarcation criteria, revealed significant viral diversity. Within Alphacoronavirus, two genomes from Atlantic Forest phyllostomid bats (Artibeus lituratus and Carollia perspicillata) formed a deeply divergent sister lineage to Amalacovirus, exhibiting a mean amino acid similarity of 76.7% with the reference genome. Within Betacoronavirus, one genome from a Caatinga phyllostomid bat (Artibeus planirostris) clustered within the recently described Ambecovirus clade, displaying 75.9% mean amino acid similarity with mormoopid-associated reference sequences. Based on these divergence levels and non-recombinant genomic architectures, we propose two novel candidate subgenera, Phyllacovirus and Phyllobecovirus, alongside potential novel viral species. Furthermore, our findings demonstrate strong host-associated structuring and biogeographical partitioning of viral lineages across Neotropical biomes. Overall, this study expands the genomic landscape of South American bat coronaviruses and underscores the importance of continuous genomic surveillance at human-wildlife interfaces.
Hoffmann, M.; Zhang, L.; Chen, N.; Moor, N.; Nehlmeier, I.; Graichen, L.; Moldenhauer, A.-S.; Dopfer-Jablonka, A.; Happle, C.; Behrens, G. M. N.; Poehlmann, S.
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SARS-CoV-2 continues to circulate globally at high levels and to evolve into new variants. Recently, a new saltation variant harbouring a highly mutated spike protein, PJ.2.1, emerged in North America. Here, we provide a brief epidemiological and virological characterization of PJ.2.1 and cocirculating variants. We report that PJ.2.1 is spreading in the USA, Canada, and Spain and mainly infects individuals aged 60 years and older, as do most other variants, with the exception of BA.3.2, which preferentially infects individuals aged 0-9 years. PJ.2.1 was less susceptible to inhibition by an antibody against ACE2 than were the other variants, indicating increased ACE2 binding. In contrast, PJ.2.1 did not show augmented evasion of antibodies from vaccinees who had received the LP.8.1-adapted vaccine compared with most other variants analysed. These results suggest that augmented ACE2 affinity rather than increased antibody evasion might drive the current, rapid spread of PJ.2.1.
Fontoura-Goncalves, C.; Goncalves, D.; Pascoal, L.; Llorente, F.; Moraga-Fernandez, A.; Contreras, M.; Silva, T.; Almeida, T.; Pinho, C.; Minayo-Martin, S.; Valencia, V.; Fasanelo, M.; Lopes, A.; Abrantes, J.; Mello, G.; Costa, J. B.; Alves, P. C.; Ramirez, E. P.; Roiz, D.; Jimenez-Clavero, M.; Hofle, U.; Queiros, J.
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Mosquito-borne orthoflaviviruses pose a significant threat to human and animal health worldwide. In Europe, West Nile (WNV), Usutu (USUV) and Bagaza (BAGV) viruses have expanded their geographic distribution and are detected with increasing frequency. Following the emergence of BAGV in 2021, we investigated the circulation dynamics and genomic diversity of orthoflaviviruses in southern Portugal, where their epidemiology remains poorly understood. Active Orthoflavivirus surveillance was conducted in birds and mosquitoes during 2021-2023 using serological and molecular assays, complemented by viral genome sequencing and phylogenomic analyses. Viral RNA was detected in 3.5% (41/1,171) of birds, while seroneutralization assays identified an overall seroprevalence of 55.3% (503/910). WNV RNA (lineage-1, strains WMed-1.2 and WMed-1.3) was detected annually in resident birds, including Alectoris rufa, Cyanopica cooki and Garrulus glandarius (1.5%, 18/1,171), and in Culex univittatus mosquitoes (0.8%, 2/255). Together with a WNV-specific seroprevalence of 28.5% (259/910) in birds, these findings support sustained local circulation. USUV RNA (Africa 3.1 sub-lineage) was detected in A. rufa in 2021 and 2023 (0.2%, 2/1,171), but seroprevalence was low (1.3%, 8/623), consistent with intermittent circulation. BAGV RNA (genotype-2) was detected only during the 2021 outbreak in A. rufa and Emberiza calandra (1.8%, 21/1,171), although BAGV-specific antibodies (6.6%, 60/910) were detected for up to two years after the outbreak, suggesting continued exposure or low-level circulation. Overall, our findings reveal contrasting circulation dynamics of orthoflaviviruses in southern Portugal. Sustained WNV circulation implies the need to strengthen avian and human surveillance in Portugal to better assess its public health risk, while the sporadic detection of USUV and BAGV underscores the value of long-term, integrated One Health surveillance for improving early warning and preparedness for emerging mosquito-borne diseases.
Hassane, F.; Lagare, A.; Yacouba, A.; Ousmane, H.; Issa, M.; Magagi, L. H.; Aoula, B.; Kaka, B. K.; Diallo, O.; Djedenam, M.; DOUTCHI, M.; Mamadou, S.
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Background: Hepatitis E virus (HEV) is highly endemic in several African countries with high mortality rate among pregnant women. The prevalence of HEV in Niger among pregnant women is unknown. We hereby aim to report the prevalence and risk factors of HEV among pregnant women in Niamey, Niger. Methods: Blood samples were collected from pregnant women attending antenatal consultation in three selected Health centers in Niamey. Data were collected for socio demographic characteristics using a structured questionnaire. Samples were tested using ELISA and qRT-PCR for anti- HEV IgM and RNA detection respectively. HEV associated risk factors were determined using multivariate logistic regression models. Results: A total of 491 pregnant women were enrolled with mean age of 26.5 years. The prevalence of anti-HEV IgM antibodies was 17.1%, while HEV RNA was detected in 3.46% of participants, indicating recent and active HEV infection. Anti-HEV IgM seropositivity was more frequent among women aged 26-30 years and those in the third trimester of pregnancy. Gravidity was significantly associated with HEV RNA positivity (p = 0.032). In multivariable analysis, the use of well water was independently associated with HEV infection (aOR = 75.70; 95% CI: 1.23-4643.20; p = 0.039). Conclusion: In view of the high seroprevalence of HEV among pregnant women, preventive measures including hygiene sensitization should be prioritized. Further studies should be conducted to assess the real impact of HEV infection on maternal and fetal health.
Tomar, S. S.; Khairnar, K.
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Background: Shotgun metagenomic pipelines routinely discard host-derived reads, which can exceed 90% of reads in low-biomass clinical samples. Whether these reads support mitochondrial heteroplasmy detection, and at what allele fraction, has not been established. Methods: Shotgun metagenomic data from 47 upper respiratory tract swabs from healthy adults in Nagpur, India, were analysed. Human Reads were recruited against the rCRS and realigned competitively to GRCh38 to remove nuclear mitochondrial segments (NUMTs). Kraken2 was used as a microbial control. Heteroplasmy was called against a pooled, substitution-specific beta-binomial error model and a leave-one-out panel of normals. The detection limit was evaluated from the substitution spectrum against gnomAD v3.1. Results: Complete mitochondrial genomes were recovered from all samples (mean depth 433X, range 9-3,029X). Competitive realignment relocated 3.22% of recruited reads to nuclear loci; microbial cross-mapping removed 0.045%. Error rates varied 12.8-fold across substitution classes, with T>A being the highest. The 134 calls had a Ti/Tv of 0.43, compared with 3.51 in gnomAD, and T>A accounted for 42.5% of calls. T>A allele fractions never exceeded 4.72%, whereas transitions reached 90.81%. At a 5% threshold, T>A calls disappeared, and Ti/Tv rose to 2.20 before plateauing; 16 calls exceeded this limit. Macrohaplogroups were assigned in 46 of 47 samples (M 22, R 23, N 1). Conclusions: Metagenomic host reads support complete mitochondrial recovery, haplogroup typing, and heteroplasmy detection for allele fractions > 5%. Below this, a T>A-dominated error process persists after NUMT removal that background-fitted models do not capture.
Khan, M. R.; Nadeem, M. S.; Coleman, J.; Cannatella, D.
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Kashmir voles (Hyperacrius) are poorly studied fossorial arvicolines of the southern Himalayan slopes, with two species recognized. We sequenced Cytb from voles collected in northern Pakistan and combined these data with existing GenBank sequences, yielding 194 tips spanning nearly all arvicoline genera. We analyzed five data sets with maximum likelihood and compared external measurements among species using principal component and linear discriminant analyses. We recovered five well-supported clades of Hyperacrius separated by ~12-14% p-distance, which we treat as distinct species. We recognize clade 1 as H. wynnei, and populations referred to H. w. traubi are genetically indistinguishable from H. w. wynnei. We recognize H. zygomaticus, new rank (clade 2), and tentatively allocate clade 5 to H. brachelix. Clades 3 and 4 likely represent undescribed species. Morphometric analyses of external measurements clearly distinguish H. wynnei but not clades 3 and 4 (overall classification accuracy 70.3%). Phylogenetic analyses including nuclear genes placed Hyperacrius as sister to a clade containing Microtini, Arvicola, Lagurini, Dinaromys, and Ellobiusini, whereas mitochondrial analyses weakly allied it with Ellobiusini. Its traditional placement in Clethrionomyini is thus unsupported, although its exact position remains unresolved. Alticola is nonmonophyletic, with A. macrotis sequences nested within Clethrionomys, likely reflecting mitochondrial capture.
Maust, B. S.; Griswold, K. A.; Khim, M.; Subramanian, S.; Staker, B.; Myler, P. J.; Kullin, B. R.; Happel, A.-U.; Varsani, A.; Jaspan, H. B.
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The Gardnerella genus includes a complex sub-taxonomy of bacterial species and subgroups which have been implicated in bacterial vaginosis. We analyzed G. leopoldii, G. swidsinski, G. piotii, and G. vaginalis genomes available in public databases and predicted proviral sequences using Cenote-Taker3. We clustered 266 prophage sequences into 140 viral genera level groupings that encode four distinct gene clusters and 19 different lysin proteins. Analysis of the bacterial and prophage sequence phylogenies reveals that while there were no specific prophage sequence lineages that infected each bacterial host, there is clustering of the prophage sequences by bacterial species within the Gardnerella genus.