Virologica Sinica最新文献

Human parainfluenza viruses (HPIV) are common viral pathogens in acute respiratory infection (ARI). We aimed to describe the epidemiological and molecular characteristics of HPIV from ARI patients. This cross-sectional study was conducted using respiratory samples from 9,696 ARI patients between 2016 and 2020 in southern China. All samples were analyzed by quantitative real-time polymerase chain reaction to determine the presence of HPIV and other common respiratory viruses. Descriptive statistics were performed to determine the temporal and population distribution of HPIV. The full-length hemagglutinin-neuraminidase (HN) gene of HPIV3-positive samples was sequenced for phylogenetic analysis. A total of 577 (6.0%) patients tested positive for HPIV, with HPIV3 being the predominant serotype, accounting for 46.8% of cases. Notably, 66.0% of these HPIV-positive cases were children aged 0-2 years. The prevalence of HPIV infections showed a decreased trend and altered peak during 2016-2020. Cough, fever, sputum production, and rhinorrhea were common respiratory symptoms in HPIV-positive patients. The majority of cases had pneumonia (63.4%). Human rhinovirus (HRV) and human coronavirus (HCoV) were the most common coinfection viruses in HPIV-positive cases, with proportions of 20.1% and 14.4%, respectively. Phylogenetic analysis revealed that the predominant lineage of HPIV3 was C3f (86.0%), followed by lineage C3a (8.0%), C3d (4.0%), and C3b (2.0%). These findings help to better understand the epidemiology of HPIV, and improve public health strategies to prevent and control HPIV infections in southern China.

Porcine reproductive and respiratory syndrome (PRRS), a highly infectious immunosuppressive disease caused by porcine reproductive and respiratory syndrome virus (PRRSV), has led to significant economic losses in the global swine industry. The complexity of preventing and controlling PRRS, compounded by the limited efficacy of current vaccines, underscores the urgent need to identify antiviral targets and develop effective therapeutics against PRRSV. From the perspective of virus-host interactions, the discovery of target molecules associated with PRRSV resistance offers a promising strategy for future disease management. In this study, we conduct a comprehensive proteomic analysis using data-independent acquisition (DIA) mode to investigate the host response throughout the acute phase of PRRSV infection. This approach provides critical insights into the regulation of host antiviral and immune pathways during acute infection, advancing our theoretical understanding of PRRSV-host interactions and host gene dynamics during this critical phase. Notably, we identified SCARB2, a major lysosomal membrane protein associated with cholesterol metabolism, as a potential regulator of PRRSV replication. These findings offer novel perspectives for the prevention and control of PRRSV, contributing to the development of targeted antiviral strategies.

Artemisia annua L. is a medicinal herb with multiple therapeutic applications, whereas its anti-influenza A virus (IAV) efficiency and mechanism of action are still unclear. Here, we investigated the inhibition activity and mechanism of A. annua leaf methanol extracts (AALME) against IAV in vitro and in vivo. Our results revealed that AALME exhibits potent anti-IAV activity by interacting with IAV particles. Mechanistically, AALME directly targets the IAV nucleoprotein (NP) protein and abolishes the nuclear import of IAV NP. AALME profoundly suppresses IAV-induced mitochondrial apoptosis via suppressing ROS-mediated AIF-dependent pathways. More importantly, we found that AALME plays a crucial role in protecting mice from IAV infection and mitigating IAV pathogenicity. This current work provides mechanistic insight into the mechanism by which AALME controls IAV infection in vitro and in vivo, potentially contributing to the development of antiviral treatments for IAV infection.

As an emerging genotype, the G9 genotype rotaviruses (RVs) are widespread among humans and pigs, and have been reported in many countries and regions in the recent years. Moreover, porcine G9 strains could cross the interspecies barrier to infect human. To investigate the epidemic trends of porcine G9 strains as well as the cross-immunoreactivity among different isolates, an epidemiological investigation about porcine G9 genotype RVs (PoRVs) was performed during the period 2020-2023 in multiple provinces of China. A total of nine representative strains were identified. The phylogenetic analysis based on viral VP7 gene showed that these strains mainly clustered with lineages III and VI, which revealed the predominant G9 PoRVs in China. Moreover, a new lineage, lineage VII, was identified, and strains of this lineage were found to be circulating in Guangdong and Taiwan. Except lineages I and IV, some isolates from other lineages could co-circulate in pigs and humans. Three G9 strains, namely 923H, 923E, and 923X, which belonged to the largest sub-lineage III, were isolated. Then, the significant cross-reactivity was observed among strains of the same or different lineages. This study is the first to systematically investigate the genetic and immunogenetic characteristics of porcine G9 genotype rotavirus in China, as well as the potential cross-species transmission between pigs and humans, providing a valuable direction for the effective prevention of porcine rotavirus.

Ephemeroviruses (EVs) are arthropod-borne rhabdoviruses and were isolated exclusively from cattle and haematophagous arthropods until two new ephemeroviruses were first identified from domestic pigs most recently. Here we report the identification of newer EVs in wild boar by meta-transcriptomic (MTT) sequencing. Further screening by specific RT-nPCR of tissue samples of 459 free-ranging wild boars collected between 2018 and 2023 from 26 provinces across China confirmed five positive wild boars in four provinces. Interestingly, two ticks especially collected from two positive wild boars were also EV positive. Finally, four complete genome sequences of wild boar ephemeroviruses (WbEVs) were obtained with two strains belonging to a new EV species, and the rest two falling into porcine ephemerovirus 2 (PoEV2) species identified from domestic pigs. Our study has further extended EV host range and demonstrated natural circulations of divergent EVs in wild boars, in which ticks may play roles. Biological implications of EV infection in wild boars should be interesting topics for future investigations.

Zika virus (ZIKV) is a mosquito-borne virus belonging to the genus Orthoflavivirus, and the family Flaviviridae. It commonly presents with febrile-like symptoms, neurological issues, and pregnancy complications in humans. Currently, there is no commercial vaccine or specific treatment available to prevent ZIKV infection. Therefore, controlling the epidemic's spread relies on preventing mosquitoes from transmitting the virus. Although various studies have explored the transmission of ZIKV between mosquitoes and vertebrate hosts, comprehensive research on potential mosquito-to-mosquito transmission of ZIKV remains limited. In this study, we conducted systematic laboratory investigations to assess the ability of ZIKV to spread among mosquitoes, and to evaluate the impact of ZIKV infection on mosquito development. Our findings revealed that ZIKV can be transmitted between Aedes aegypti mosquitoes both vertically and horizontally, through oviposition and contact between mosquitoes of the same or opposite sex. Additionally, we observed that ZIKV infection resulted in a reduction in the number of mosquito eggs but an increase in their size. The widespread distribution of ZIKV in infected mosquitoes and the altered levels of hormone related genes following viral infection were noted, which may contribute to viral transmission among mosquitoes and affect mosquito development. This research provides systematic experimental evidence of ZIKV transmission among mosquitoes, which is crucial for developing novel strategies to disrupt the spread of orthoflaviviruses and other mosquito-borne pathogens.