China Virus Research Articles

A series of patients infected with the emerging tick-borne Yezo virus in China: an active surveillance and genomic analysis

Yezo virus (YEZV) is an emerging tick-borne pathogen, which was initially reported in Japan in 2021. Only one patient had been reported in China so far. We aimed to describe the epidemiological, clinical, and laboratory findings of a series of patients, and to characterise the viral genomes of YEZV. In this active surveillance and genomic analysis, we conducted active surveillance at Mudanjiang Forestry Central Hospital, Heilongjiang Province of northeast China. Participants were eligible for inclusion if they sought medical care for a recent tick bite between May 1 and July 31, in 2022 and 2023, and between May 1 and July 10, in 2024. We collected sera from participants to detect YEZV infection by meta-transcriptomic sequencing, real-time RT-PCR, and indirect immunofluorescence assay. We isolated YEZV by cell culture and characterised the pathogen by morphological and phylogenetic analyses. A series of 18 patients with YEZV infection (12 male and six female; median age 53 years, IQR 45-60) were identified among 988 participants. The patients presented with fever (18 patients, 100%), headache (ten patients, 56%), dizziness (nine patients, 50%), malaise (three patients, 17%), lumbago (three patients, 17%), and cough (three patients, 17%). Nine (50%) patients had rash around the tick bite site and four (22%) had lymphadenopathy. Nine (50%) patients had gastrointestinal symptoms, and five (28%) had neurological symptoms. We observed leukopenia in ten (63%) and thrombocytopenia in five (31%) of 16 assessed patients. Elevated hepatic transaminase concentrations were identified in 13 (72%) of all 18 patients, lactate dehydrogenase or α-hydroxybutyric dehydrogenase in nine (50%), serum amyloid protein A in 13 (72%), and hypersensitive C-reactive protein in ten (56%). Eight (7%) of 119 Ixodes persulcatus ticks removed from participants were positive for YEZV. Three YEZV strains were isolated from the sera of patients. Ten viral genomes were obtained from five patients, a blood-sucking I persulcatus removed from a participant, and four host-questing tick samples collected in the areas where patients were identified or in the adjacent region. Phylogenetic analyses revealed that YEZVs in either patients or ticks were divided into two clades, each with distinct mutations. Awareness of YEZV infection is important and clinicians should consider the virus when diagnosing patients with suitable symptoms. National Key Research and Development Program of China. For the Chinese translation of the abstract see Supplementary Materials section.

Recombinant characterization and pathogenicity of a novel L1C RFLP-1-4-4 variant of porcine reproductive and respiratory syndrome virus in China

Porcine reproductive and respiratory syndrome (PRRS) is one of the most significant diseases affecting the pig industry worldwide and is caused by the PRRS virus (PRRSV), which has complex genetic variation due to frequent mutations, indels, and recombination. The emergence of PRRSV L1C.5 in 2020 in the United States has raised worldwide concerns about PRRSV with the RFLP 1-4-4 pattern and lineage 1C. However, studies on the pathogenic characteristics, epidemiological distribution, and effectiveness of vaccines against PRRSV with L1C and RFLP1-4-4 pattern in China are still insufficient. In this study, a novel recombinant variant of PRRSV with RFLP 1-4-4 and lineage 1C features, different from L1C.5 in the United States, was isolated in China in 2021. In pathogenicity experiments in specific pathogen-free piglets or farm piglets, 60–100% of artificially infected experimental piglets died with high fever and respiratory symptoms. Inflammatory cytokine and chemokine levels were upregulated in infected piglets. A commercially modified live vaccine against highly pathogenic PRRSV did not provide effective protection when the vaccinated piglets were challenged with the novel L1C-1-4-4 variant. Therefore, this strain merits special attention when devising control and vaccine strategies. These findings suggest that extensive joint surveillance is urgently needed and that vaccine strategies should be updated to prevent the disease from spreading further.

Characterization, phylogeny and recombination of Rhynchosia yellow mosaic virus infecting Rhynchosia minima, a wild relative of pigeonpea (Cajanus cajan) from India.

Rhynchosia minima grown at Indian Institute of Pulses Research, Kanpur, India, showed yellow mosaic symptoms on leaves and were suspected to be caused by begomovirus(es). Leaves from five different plants (Rhm1-Rhm5) were tested for the presence of four viruses in PCR. PCR assays revealed the presence of mungbean yellow mosaic India virus in four samples, whereas one sample (Rhm2) was negative. Processing of Rhm2 sample using rolling circle amplification and restriction digestion indicated the presence of DNA molecules of ~ 2.6-2.7kb. These molecules were sequenced after cloning and found to be of 2741 and 2658 nucleotides in size. BLAST analysis revealed that DNA-A (OQ269467) and DNA-B (OQ269468) molecules of rhynchosia yellow mosaic virus (RhYMV) with 99.09% and 93.74% nucleotide similarity with DNA-A (KP752090) and DNA-B (KP752091) of the RhYMV isolate, respectively. These sequences had a genome organization typical of legume-infecting Old World bipartite begomoviruses. Full genome sequences obtained from Rhm2 are, therefore, considered to be an isolate of RhYMV, designated as RhYMV-IN-Knp. The phylogenetic analysis revealed that RhYMV-IN-Knp was grouped with other isolates of RhYMV followed by Cajanus scarabaeoides yellow mosaic virus. DNA-A of RhYMV-IN-Knp showed two recombination events. The Old World bipartite begomovirus squash leaf curl China virus (AM260205) was identified as the major parent, whereas New World bipartite begomovirus rhynchosia golden yellow mosaic Yucatan virus (EU021216) was identified as the minor parent. RhYMV holds the potential of infecting cultivated legume crops, therefore regular monitoring is crucial especially for pigeonpea breeding programs.

African swine fever virus in China: the diagnostic target gene (B646L) has acquired multi-point mutations

African swine fever virus in China: the diagnostic target gene (B646L) has acquired multi-point mutations

Comparative transcriptome analysis of tobacco plants reveals differences in reactive oxygen species activated defenses following the infestations of non-viruliferous and TYLCCNV-viruliferous whitefly Mediterranean

ABSTRACT Tomato yellow leaf curl China virus (TYLCCNV) viruliferous Mediterranean (MED) whitefly infestation in tobacco plants elevated hydrogen peroxide (H2O2) levels more than non-viruliferous ones. To unravel the underlying mechanisms behind the phenomenon, comparative analyses of plant transcriptome and enzyme activities of reactive oxygen species (ROS) scavengers were conducted in this study. Compared to the control, a total of 4032 and 6853 differentially expressed genes (DEGs) were identified in the plants following the infestations of non-viruliferous and TYLCCNV-viruliferous MED, respectively. Gene ontology analysis of DEGs suggested substantial transcriptional reprogramming of diverse cellular processes, particularly in the biotic stress response pathways of tobacco plants. Respiratory burst oxidase homologs related genes and important kinases putatively involved in plant defense were differentially modulated in tobacco plants in response to the non-viruliferous and TYLCCNV-viruliferous whitefly MED infestation. The analysis reported here lays out a strong foundation for future investigations into the mechanisms of ROS-associated plant defense mediating the interactions between B. tabaci and begomoviruses.

Identification of a newly discovered virus from Culex and Armigeres mosquitoes in China

Mosquito associated virus have always been a significant threat to global health. Metagenomics offers a straightforward and quantitative means to acquire the information of novel virus and has greatly enriched the content of mosquito associated virus databases. During an entomological surveillance for arthropod-borne viruses in China, we identified a previously unrecognized virus from mosquitoes, temporarily named Huajieling virus. In this study, a total of 3,960 mosquitoes were collected and then divided into 91 pools, according to location and species. QRT-PCR and nested PCR were performed to confirm the presence of Huajieling virus. Its genomic features and phylogenetic relationships were further analyzed. Our results showed that Huajieling virus was detected in 7 of the 91 mosquito pools and that the minimum infection rate (MIR) was 0.18% (7/3,960). One complete genome sequence and 2 viral partial sequences were obtained from the Huajieling virus-positive pools. Pairwise distances analysis indicated that these amplified sequences shared high nucleotide identity. Phylogenetic analysis demonstrated that Huajieling virus is most closely related to Wufeng shrew picorna-like virus 43, which belonging to Picornavirales. Further analyses indicated that Huajieling virus is a new member of unclassified Picornavirales, and is intermediate between the family Caliciviridae and Secoviridae in taxonomic status.

From a ‘Peaceful and Prosperous China’ to ‘the China Virus’: Examining the Framing of China Through American Political Rhetoric

Abstract The period comprising the past thirty-two years since the collapse of the Soviet Union has seen a range of approaches taken by the United States in handling its relationship with China. Launched in November 2011, the ‘Pivot to Asia’ policy approach entailed new levels of engagement with ‘a peaceful and prosperous China’, but on the most challenging issues this approach also brought increasing confrontation. The West (in this case the United States) has a history of utilising Orientalist-style, ‘us vs them’ dichotomies to manipulate unequal relations of power with the East (known as the ‘Orient’) throughout history (originally with middle-eastern nations). By using tenets from Edward Said’s Orientalism and critical discourse analysis adapted from Normal Fairclough’s 3-dimensional model, this article seeks to establish whether the foreign policy rhetoric of the United States has shifted to frame China through an Orientalist worldview since the Obama Administration’s “Pivot to Asia” strategy in late 2011. The article analyses 52 speeches from the Obama and Trump Administrations, finding evidence of pro-orientalist themes and language being adopted for both. Whilst utilised to a lower degree, these ‘us vs them’ dichotomies do exist under President Obama’s more accommodating and calmer linguistic-style, being intertwined with language designed to project an image of welcoming cooperation (albeit in a condescending, back-handed way). The use of orientalist themes is more prominently provable under President Trump, with almost all major speeches pertaining to China containing high usage of orientalist tropes in a more openly xenophobic, racist fashion.

Characterization of the emerging recombinant infectious bronchitis virus in China.

Infectious bronchitis virus (IBV) can cause serious harm to poultry industry. It is belong to Coronaviridae which is highly variable. A kind of emerging recombinant IBV (ahysx-1) has been detected in chicken from China in 2016. To understand the epidemiology and characterization of the emerging recombinant IBV, 35,455 samples of chickens from the 15 provinces in China were collected and detected. One hundred and ninety-six out of the 537 flocks (positive rate, 36.49%), and 908 out of 35,455 samples (positive rate, 2.56%) were positive in the detection. The results showed that the emerging recombinant IBV was pandemic in China. Thirteen emerging recombinant IBV isolates were selected and continuous subcultured to the fourth generation and analyzed by Next-generation sequencing. Compared with the reported sequence of ahysx-1, the genomic analysis showed that multiple position insertions and deletions were in 1a gene, 3b gene, M gene and N gene. The identity of the S gene nucleotide sequence between all the 13 emerging recombinant IBV isolates and reference stain ahysx-1 were 98.1-99.1%, while the identity of amino acid sequence were 98.0-99.8%. To better understand the recombination mechanism of the emerging recombinant IBV, the genomic sequence of the 13 isolates were compared with turkey coronavirus or guinea fowl coronavirus. The results suggest that all the 13 emerging recombinant IBV isolates were likely to be the recombination of turkey coronavirus or guinea fowl coronavirus with IBV. Turkey coronavirus or guinea fowl coronavirus as minor parents are the donors of S gene. The major parents donors of the genome backone of these recombination events were lineages GI-19 or GVI-1 of IBV. One isolate (IBV/chicken/Henan/H1173/2021) was selected for pathogenicity analysis. The results showed that IBV/chicken/Henan/H1173/2021 was avirulent to SPF embryonated eggs, but could cause intestinal symptoms in of chicks. This study provides a foundation for understanding the epidemic situation and characterization of the emerging recombinant IBV. It is of great significance for the prevention and control of avian coronavirus infection.

ELISA genotyping of hepatitis B virus in China with antibodies specific for genotypes B and C

Hepatitis B virus (HBV) causes hepatitis B (HB) and distinct HBV genotypes can lead to different prognoses. However, HBV genotyping is rarely done in clinics, because the traditional method by PCR-based DNA sequencing is impractical for clinical diagnosis with tedious process and low success rate. Herein, we have established an ELISA-based genotyping method to quickly determine the HBV genotypes of HB patients in China. First, two commercial antibodies, 16D12 and 6H3 specific for HBV genotypes B and C respectively, are chosen as capture antibodies, since these two genotypes dominate in China. Then two home-made genotype-specific antibodies, B19 and C04, are used as the detection antibodies for genotypes B and C in sandwiched ELISA. The ELISA kit shows high sensitivity (> 95%) and specificity (> 95%) in detecting genotypes B and C of Chinese HB patients. Moreover, the ELISA kit has demonstrated higher success rate (98.7%) than PCR-based DNA sequencing (93.5%) and a commercial PCR-based genotyping kit (92.2%) for sera with HBV DNA ≥ 1000 IU/mL and HBsAg ≥ 250 IU/mL. Such an advantage is more obvious for the sera with HBV DNA < 1000 IU/mL. The kappa analysis between the ELISA and PCR-based DNA sequencing results exhibits a kappa of 0.836, indicating a good correlation.

‘The coronavirus is a formidable foe’: children’s multimodal articulations of SARS-CoV-2 virus and COVID-19 pandemic experiences in China

Objective This study explored children’s post-pandemic articulations regarding the coronavirus along with their lived experiences during the COVID-19 pandemic. Design A qualitative survey featuring drawings, comments, questions and follow-up interviews was employed to gather data from 108 infected children aged 13 to 14 from two middle schools in China. This multimodal approach allowed for a rich capture of the children’s articulations of their pandemic experiences. Results Children’s multimodal articulations conveyed not only the biological features of, but also their emotional reactions to the coronavirus. The pandemic had disrupted children’s lives, making online learning, sleep and screen engagement dominant in their daily routines, while also compounding children’s unhappiness primarily due to restrictions on social interactions. Children associated the coronavirus with biological, medical, psychological and social aspects. Increased sanitisation and hygiene habits featured their pre‐to-post pandemic changes. Furthermore, children exhibited an awareness regarding preventive measures and transmission modes, albeit with certain biases or gaps. Their misunderstandings about recuperative strategies merit clarification. Conclusion The COVID-19 pandemic has had profound and multifaceted impacts on children’s emotional well-being, daily routines, social interactions, education, and health-related behaviors. Children’s multimodal articulations revealed a spectrum of adverse effects caused by the pandemic, calling for targeted health interventions to mitigate these negative effects while also equipping children with resilience and coping skills for navigating future health crises. Incorporating children’s perspectives and experiences into future pandemic preparedness and health promotion strategies is essential for addressing their vulnerabilities and ensuring their overall well-being during public health crises.

The 2023 National Proficiency Test for molecular detection of shrimp infectious myonecrosis virus (IMNV) in China

Infectious myonecrosis virus (IMNV), an emerging virus that can cause severe viral disease in penaeid shrimp, was first confirmed to have spread to China in 2020. In order to standardize diagnostic procedures and reliable detection capability, and to evaluate the performances of aquatic clinical diagnostic laboratories, the competent authority has launched a proficiency test (PT) scheme for the molecular detection of IMNV in China from the year of 2023. In the ring test of IMNV-PT 2023, five tissue samples containing different concentrations of IMNV were provided as a panel of test samples. A total of 68 laboratories participated in the PT test of qualitative and quantitative analysis of the five samples using standard molecular assays. The results showed that 92.65 % (63/68) of the participants correctly reported all samples in the panel using Real-time reverse transcription PCR and 62 participants achieved satisfactory results, one participant using conventional PCR and four participants had not completed the test. Out of the 62 participants in the z-scores analysis, 88.71 % (55/62) achieved acceptable ZB-scores, with two outlier laboratories and five laboratories being questionable. Additionally, 98.39 % (61/62) achieved ZW-scores, with only one laboratory being questionable. Furthermore, the national PT conducted in the present study proved to be an effective tool for evaluating laboratory performance in IMNV molecular testing. This assessment can aid in improving the capabilities of IMNV molecular testing of the participating laboratories, and also provided technical supporting to enhance the national response to IMN outbreaks.

Molecular Identification and Genetic Diversity Analysis of Papaya Leaf Curl China Virus Infecting Ageratum conyzoides.

Papaya leaf curl China virus (PaLCuCNV) is a damaging plant pathogen causing substantial losses to crop. The complete genomes of three PaLCuCNV isolates from Ageratum conyzoides were obtained and combined with the 68 reference isolates in GenBank for comprehensive genetic diversity analyses using specialized computational tools. Sequence alignment revealed nucleotide sequence similarity ranging from 85.3% to 99.9% among 71 PaLCuCNV isolates. Employing phylogenetic analysis, 71 PaLCuCNV sequences were clustered into five groups, with no significant correlation observed between genetic differentiation and either host species or geographical origin. Additionally, 13 recombination events across all PaLCuCNV isolates were identified. Genetic diversity analysis indicated the ongoing expansion and evolution of PaLCuCNV populations, supported by a neutral model. Moreover, significant genetic differentiation was observed among distinct viral populations, primarily attributed to genetic drift. Overall, our findings provide valuable insights into the detection, genetic variation, and evolutionary dynamics of PaLCuCNV.

Transcriptomic profiling reveals the complex interaction between a bipartite begomovirus and a cucurbitaceous host plant

BackgroundBegomoviruses are major constraint in the production of many crops. Upon infection, begomoviruses may substantially modulate plant biological processes. While how monopartite begomoviruses interact with their plant hosts has been investigated extensively, bipartite begomoviruses-plant interactions are understudied. Moreover, as one of the major groups of hosts, cucurbitaceous plants have been seldom examined in the interaction with begomoviruses.ResultsWe profiled the zucchini transcriptomic changes induced by a bipartite begomovirus squash leaf curl China virus (SLCCNV). We identified 2275 differentially-expressed genes (DEGs), of which 1310 were upregulated and 965 were downregulated. KEGG enrichment analysis of the DEGs revealed that many pathways related to primary and secondary metabolisms were enriched. qRT-PCR verified the transcriptional changes of twelve selected DEGs induced by SLCCNV infection. Close examination revealed that the expression levels of all the DEGs of the pathway Photosynthesis were downregulated upon SLCCNV infection. Most DEGs in the pathway Plant-pathogen interaction were upregulated, including some positive regulators of plant defenses. Moreover, the majority of DEGs in the MAPK signaling pathway-plant were upregulated.ConclusionOur findings indicates that SLCCNV actively interact with its cucurbitaceous plant host by suppressing the conversion of light energy to chemical energy and inducing immune responses. Our study not only provides new insights into the interactions between begomoviruses and host plants, but also adds to our knowledge on virus-plant interactions in general.

Bayesian phylogeographic inference of wheat yellow mosaic virus in China and Japan suggests that the virus migration history coincided with historical events

Wheat yellow mosaic virus (WYMV) is one of the most serious viral pathogens causing reductions in wheat yield in East Asia. We investigated the phylodynamics of WYMV by analysing the CP, VPg and P1 genes to understand the origin and dispersal of the virus. A Bayesian phylogenetic analysis revealed that the most recent common WYMV ancestor occurred in approximately 1742 (95% credibility interval, 1439–1916) CE (Common Era), and the evolutionary rates of the VPg, CP and P1 genes were 6.669 × 10−4 (95% credibility interval: 4.575 × 10−4–8.927 × 10−4), 2.468 × 10−4 (95% credibility interval: 1.667 × 10−4–3.338 × 10−4) and 5.765 × 10−5 (95% credibility interval: 3.285 × 10−6–1.252 × 10−4), respectively. Our phylogeographic analysis indicated that the WYMV population may have originated in Henan Province, China, first spreading to Japan in the mid-19th century and stopping after the Japanese surrender in World War II. The second wave spread to Japan from Shandong Province, China, in approximately 1977, a few years after the establishment of diplomatic relations between China and Japan. Before the founding of the People's Republic of China, Henan Province was the emigration centre of WYMV in East Asia, and after the late 20th century, Jiangsu and Shandong Provinces were also the virus emigration centres in East Asia. In addition, there were two migration pathways from Japan to Jiangsu and Shandong Provinces, China, in approximately 1918 and approximately 1999 respectively. Our results suggest that the wide spread of WYMV in East Asia is strongly related to human factors.

The spatiotemporal analysis of SARS-CoV-2 transmission in China since the termination of the dynamic zero-COVID policy

China's dynamic zero-COVID policy has effectively curbed the spread of SARS-CoV-2, while inadvertently creating immunity gaps within its population. Subsequent surges in COVID-19 cases linked to various SARS-CoV-2 lineages post-policy termination necessitate a thorough investigation into the epidemiological landscape. This study addresses this issue by analyzing a comprehensive dataset of 39,456 high-quality genomes collected nationwide over an 11-month period since policy termination. Through lineage assignment, phylogenetic analysis, pandemic pattern comparison, phylodynamic reconstruction, and recombination detection, we found that China's post-epidemic period could be divided into three stages, along with dynamic changes in dominant lineages. Geographical clustering of similar lineages implies the importance of cross-border cooperation among neighboring regions. Compared to the USA, UK, and Japan, China exhibits unique trajectories of lineage epidemics, characterized by initial lagging followed by subsequent advancement, indicating the potential influence of diverse prevention and control policies on lineage epidemic patterns. Hong Kong, Shanghai, and Hubei emerge as pivotal nodes in the nationwide spread, marking a shift in the transmission center from east to central regions of China. Although China hasn't experienced significant variant emergence, the detection and validation of the novel recombination event, XCN lineage, underscore the ongoing virus evolution. Overall, this study systematically analyzes the spatiotemporal transmission of SARS-CoV-2 virus in China since the termination of the dynamic zero-COVID policy, offering valuable insights for regional surveillance and evidence-based public health policymaking.

Identification of concurrent infection with Jaagsiekte sheep retrovirus and maedi-visna virus in China.

Ovine pulmonary adenomatosis (OPA) and maedi-visna disease (MVD) are chronic and progressive infectious diseases in sheep caused by Jaagsiekte sheep retrovirus (JSRV) and maedi-visna virus (MVV), respectively. To investigate the pathological changes and conduct viral gene analysis of OPA and MVD co-occurrence in Inner Mongolia, China. Using gross pathology, histopathology, immunohistochemistry, ultrastructural pathology, PCR, and sequence analysis, we investigated the concurrent infection of JSRV and MVV in 319 Dorper rams slaughtered in a private slaughterhouse in Inner Mongolia, in 2022. Of the 319 rams included, 3 showed concurrent JSRV and MVV infection. Gross lung pathology showed diffuse enlargement, consolidation, and greyish-white miliary nodules on the lung surface; the trachea was filled with a white foamy fluid; hilar and mediastinal lymph nodes were significantly enlarged. Histopathology results revealed typical OPA and MVD lesions in the lung tissue. Immunohistochemical results were positive for JSRV envelope protein (Env) in the tumor cells and MVV CA in alveolar macrophages. Transmission electron microscopy showed several virions and autophagosomes in the lung tissue, severely damaged mitochondria, and the induced mitophagy. Nucleotide sequences obtained for JSRV env and MVV gag showed the highest homology with the Inner Mongolian strains of JSRV env (JQ837489) and MVV gag (MW248464). Our study confirmed that OPA and MVD co-occurrence and identified the pathological changes in Inner Mongolia, China, thereby providing references for the identification of concurrent JSRV and MVV infections.

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Following a season of diligent cultivation, the rice plants are ready for harvest. However, some rice plants have not headed yet and so are left unharvested in the fields. This delay is caused by infection with rice stripe mosaic virus, a newly emerged rice virus in southern China. Chen et al. (pages 2000‐2016) demonstrated that the virus‐encoded protein P6 hijacks the rice heading‐related E3 ubiquitin ligase HAF1, leading to delayed heading. The infected plants that are left unharvested offer a conducive environment for the virus and its carrier, the leafhopper Recilia dorsalis, to overwinter.

Decoding the RNA viromes in shrew lungs along the eastern coast of China

Shrews being insectivores, serve as natural reservoirs for a wide array of zoonotic viruses, including the recently discovered Langya henipavirus (LayV) in China in 2018. It is crucial to understand the shrew-associated virome, viral diversity, and new viruses. In the current study, we conducted high-throughput sequencing on lung samples obtained from 398 shrews captured along the eastern coast of China, and characterized the high-depth virome of 6 common shrew species (Anourosorex squamipes, Crocidura lasiura, Crocidura shantungensis, Crocidura tanakae, Sorex caecutiens, and Suncus murinus). Our analysis revealed numerous shrew-associated viruses comprising 54 known viruses and 72 new viruses that significantly enhance our understanding of mammalian viruses. Notably, 34 identified viruses possess spillover-risk potential and six were human pathogenic viruses: LayV, influenza A virus (H5N6), rotavirus A, rabies virus, avian paramyxovirus 1, and rat hepatitis E virus. Moreover, ten previously unreported viruses in China were discovered, six among them have spillover-risk potential. Additionally, all 54 known viruses and 12 new viruses had the ability to cross species boundaries. Our data underscore the diversity of shrew-associated viruses and provide a foundation for further studies into tracing and predicting emerging infectious diseases originated from shrews.

Phylogenetic and Genetic Variation Analysis of Porcine Epidemic Diarrhea Virus in East Central China during 2020-2023.

Porcine epidemic diarrhea virus (PEDV) is a major causative pathogen of a highly contagious, acute enteric viral disease. This study evaluated the emergence of nine variants in Jiangsu and Anhui provinces of China from 2020 to 2023. S gene-based phylogenetic analysis indicated that three variants belong to the G1c subgroup, while the other six strains are clustered within the G2c subgroup. Recombination analyses supported that three variants of the G1c subgroup were likely derived from recombination of parental variants FR0012014 and a donor variant AJ1102. In addition, there are novel mutations on amino acid 141-148 and these likely resulted in changes in antigenicity in the three variants. These results illustrated that the study provides novel insights into the epidemiology, evolution, and transmission of PEDV in China.

The evolution, complexity, and diversity of swine influenza viruses in China: A hidden public health threat

Swine influenza viruses (SIVs), including H1N1, H1N2, and H3N2, have spread throughout the global pig population. Potential pandemics are a concern with the recent sporadic cross-species transmission of SIVs to humans. We collected 1421 samples from Guangdong, Fujian, Henan, Yunnan and Jiangxi provinces during 2017–2018 and isolated 29 viruses. These included 21H1N1, 5H1N2, and 3H3N2 strains. Genome analysis showed that the domestic epidemic genotypes of H1N1 were mainly G4 and G5 reassortant EA swine H1N1. These genotypes have a clear epidemic advantage. Two strains were Clade 6B.1 pdm/09H1N1, suggesting a possible pig-to-human transmission route. Notably, three new H1N2 genotypes were identified using the genomic backbones of G4 or G5 viruses for recombination. The identification of various subtypes and genotypes highlight the complexity and diversity of SIVs in China and need for continuous monitoring of SIV evolution to assess the risks and prepare for potential influenza pandemics.