Backgrounds: A contemporary public health challenge is the increase in the prevalence rates of herpes zoster (HZ) worldwide. Methods: In this work, the gE gene structure was analyzed using bioinformatics techniques, and three plasmids of varying lengths, tgE537, tgE200, and tgE350, were expressed in Chinese hamster ovary (CHO) cells. These proteins were used to immunize BALB/c mice with Al/CpG adjuvant; ELISPOT and FCM were used to evaluate cellular immunity; and ELISA, VZV microneutralization, and FAMA assays were performed to detect antibody titers. Results: Target protein concentrations of 1.8 mg/mL for tgE537, 0.15 mg/mL for tgE200 and 0.65 mg/mL for tgE350 were effectively produced. The ability of the three protein segments to stimulate CD4+ and CD8+ T cells, as well as to cause lymphocytes to secrete IFN-γ and IL-4, did not significantly differ from one another. Both tgE537 and tgE350 were capable of generating VZV-specific antibodies and neutralizing antibodies, while tgE350 had the highest neutralizing antibody titer (4388). There was no equivalent humoral immune response induced by tgE200. Conclusions: The results of this investigation provide the groundwork for the creation of HZ recombinant vaccines using truncated proteins as antigens.

IntroductionThe Hedi virus (HEDV) and Wuxiang virus (WUXV) are newly discovered Bunyaviruses transmitted by sandflies. The geographical distribution of isolation of these two viruses continues to expand and it has been reported that WUXV causes neurological symptoms and even death in suckling mice. However, little is known about the prevalence of the two viruses in mammalian infections.MethodsIn order to understand the infection status of HEDV and WUXV in humans and animals from regions where the viruses have been isolated, this study used Western blotting to detect the positive rates of HEDV and WUXV IgG antibodies in serum samples from febrile patients, dogs, and chickens in the forementioned regions.ResultsThe results showed that of the 29 human serum samples, 17.24% (5/29) tested positive for HEDV, while 68.96% (20/29) were positive for WUXV. In the 31 dog serum samples, 87.10% (27/31) were positive for HEDV and 70.97% (22/31) were positive for WUXV, while in the 36 chicken serum samples, 47.22% (17/36) were positive for HEDV, and 52.78% (19/36) were positive for WUXV.DiscussionThese findings suggest there are widespread infections of HEDV and WUXV in mammals (dogs, chickens) and humans from the regions where these viruses have been isolated. Moreover, the positive rate of HEDV infections was higher in local animals compared to that measured in human specimens. This is the first seroepidemiological study of these two sandfly-transmitted viruses. The findings of the study have practical implications for vector-borne viral infections and related zoonotic infections in China, as well as providing an important reference for studies on the relationship between sandfly-transmitted viruses and zoonotic infections outside of China.

Objective:Viral encephalitis is an infectious disease severely affecting human health. It is caused by a wide variety of viral pathogens, including herpes viruses, flaviviruses, enteroviruses, and other viruses. The laboratory diagnosis of viral encephalitis is a worldwide challenge. Recently, high-throughput sequencing technology has provided new tools for diagnosing central nervous system infections. Thus, In this study, we established a multipathogen detection platform for viral encephalitis based on amplicon sequencing.Methods:We designed nine pairs of specific polymerase chain reaction (PCR) primers for the 12 viruses by reviewing the relevant literature. The detection ability of the primers was verified by software simulation and the detection of known positive samples. Amplicon sequencing was used to validate the samples, and consistency was compared with Sanger sequencing.Results:The results showed that the target sequences of various pathogens were obtained at a coverage depth level greater than 20×, and the sequence lengths were consistent with the sizes of the predicted amplicons. The sequences were verified using the National Center for Biotechnology Information BLAST, and all results were consistent with the results of Sanger sequencing.Conclusion:Amplicon-based high-throughput sequencing technology is feasible as a supplementary method for the pathogenic detection of viral encephalitis. It is also a useful tool for the high-volume screening of clinical samples.

Objective Genotypes (G) 1, 3, and 5 of the Japanese encephalitis virus (JEV) have been isolated in China, but the dominant genotype circulating in Chinese coastal areas remains unknown. We searched for G5 JEV-infected cases and attempted to elucidate which JEV genotype was most closely related to human Japanese encephalitis (JE) in the coastal provinces of China. Methods In this study, we collected serum specimens from patients with JE in three coastal provinces of China (Guangdong, Zhejiang, and Shandong) from 2018 to 2020 and conducted JEV cross-neutralization tests against G1, G3, and G5. Results Acute serum specimens from clinically reported JE cases were obtained for laboratory confirmation from hospitals in Shandong (92 patients), Zhejiang (192 patients), and Guangdong (77 patients), China, from 2018 to 2020. Seventy of the 361 serum specimens were laboratory-confirmed to be infected with JEV. Two cases were confirmed to be infected with G1 JEV, 32 with G3 JEV, and two with G5 JEV. Conclusion G3 was the primary infection genotype among JE cases with a definite infection genotype, and the infection caused by G5 JEV was confirmed serologically in China.

Wuxiang virus (WUXV) is the first sandfly-borne Phlebovirus isolated from Phlebotomus chinensis collected in China and has been established as a consistent viral presence in the local sandfly populations of both Wuxiang County and Yangquan City. However, its distribution in the Shanxi Province remains unclear. In this study, three novel WUXV strains were isolated from sandflies collected from Jiexiu City, Shanxi Province, China, in 2022. Subsequently, whole-genome sequences of these novel strains were generated using next-generation sequencing. The open reading frame (ORF) sequences of the WUXV strains from the three locations were subjected to gene analysis. Phylogenetic analysis revealed that WUXV belongs to two distinct clades with geographical differences. Strains from Wuxiang County and Yangquan City belonged to clade 1, whereas strains from Jiexiu City belonged to clade 2. Reassortment and recombination analyses indicated no gene reassortment or recombination between the two clades. However, four reassortments or recombination events could be detected in clade 1 strains. By aligning the amino acid sequences, eighty-seven mutation sites were identified between the two clades, with seventeen, sixty, nine, and one site(s) in the proteins RdRp, M, NSs, and N, respectively. Additionally, selection pressure analysis identified 17 positively selected sites across the entire genome of WUXV, with two, thirteen, one, and one site(s) in the proteins RdRp, M, NSs, and N, respectively. Notably, sites M-312 and M-340 in the M segment not only represented mutation sites but also showed positive selective pressure effects. These findings highlight the need for continuous nationwide surveillance of WUXV.

Background: Songling virus (SGLV) is a spherical, enveloped, fragmented, negative-stranded RNA virus belonging to the genus Orthonairovirus in the Nairoviridae family. SGLV is transmitted by ticks and can cause disease in humans. This study identified and characterized SGLV in Haemaphysalis concinna ticks collected in 2023 in the Yanbian Korean Autonomous Prefecture (China) near the China-North Korea border. Methods: A real-time quantitative polymerase chain reaction (RT-qPCR) was used to screen for SGLV nucleic acid in ticks. Baby hamster kidney (BHK-21) and African green monkey kidney (Vero) cells were used to isolate strains of SGLV from nucleic acid-positive samples through three successive passages. Next-generation sequencing and phylogenetics methods were used to characterize the SGLVs. Results: Of the 1659 ticks collected from 6 towns in the Yanbian Korean Autonomous Prefecture near the China-North Korea border, positive SGLV nucleic acid results were identified in 19 H. concinna tick pools from Helong and Longjing towns. This discovery led to the extraction of 17 SGLV genome sequences. Homology analysis that compare the newly discovered L, M, and S segments of SGLV strain HLJ1202 revealed nucleotide similarities ranging from 95.5%–97.1%, 91.9%–98.9%, and 98.3%–99.2%, respectively, and amino acid similarities ranging from 95.7%–97.4%, 97.1%–98.8%, and 98.2%–98.9%, respectively. Six distinct clades, characterized by specific geographic locations and host organisms, were identified on the Maximum Likelihood tree of the L segment. The YB129 and YB150 isolates demonstrated SGLV nucleic acid replication across three successive passages in Vero cells, as evidenced by the decrease in RT-qPCR Ct values. Conclusion: This study marks the initial identification of SGLV in H. concinna within the Yanbian Korean Autonomous Prefecture.

Objective:To establish a rapid method for the detection of varicella-zoster virus (VZV) by recombinase-aid amplification (RAA).Methods:The whole genome sequences of VZV were downloaded from the global shared database for comparison and analysis. Specific primers and probe were designed for the four conserved genes respectively and the optimal combination was selected. The optimal reaction system was selected through the concentration gradient of primers and probes, and a fluorescence RAA detection method was established. The sensitivity of the method was evaluated with VZV positive plasmid standard and clinical samples with gradient dilution, the repeatability of the method was evaluated with the lowest detectable limit concentration of positive plasmid standard, and the specificity of other viral nucleic acid method was evaluated. At the same time, this method and quantitative real-time PCR (qPCR) were used to detect clinical samples and the result were compared.Results:The optimal combination of primer pair F2/R2 and probe P2 targeting open reading frame (ORF) 28 gene was selected. Considering the cost factor, the optimal primer concentration was set at 500 nmol/L and the optimal probe concentration was 280 nmol/L. The minimum detection limit was 10 1 copies/μL, and the minimum clinical positive samples with a Ct value of 36.027 could be detected, and the result of repeated experiments were consistent. The method has no cross-reaction with other viral nucleic acids. The detection rate of clinical positive samples was 93.33%, which was almost identical to that of qPCR. Conclusions:This method is simple to operate with high sensitivity, strong specificity, low requirements for experimental conditions, visual detection result, and can detect VZV nucleic acid in samples within 20 minutes, which is a rapid VZV detection method that can be considered for clinical use for detection.

The Tembusu virus (TMUV), a member of the Flaviviridae family, can be transmitted via mosquitoes and cause poultry disease. In 2020, a strain of TMUV (YN2020-20) was isolated from mosquito samples collected in Yunnan province, China. In vitro experiments showed that TMUV-YN2020-20 produced a significant cytopathic effect (CPE) in BHK, DF-1, and VERO cells, while the CPE in C6/36 cells was not significant. Phylogenetic analysis revealed that the strain belonged to Cluster 3.2 and was closely related to the Yunnan mosquito-derived isolates obtained in 2012 and the Shandong avian-derived isolate obtained in 2014. Notably, TMUV-YN2020-20 developed five novel mutations (E-V358I, NS1-Y/F/I113L, NS4A-T/A89V, NS4B-D/E/N/C22S, and NS5-E638G) at loci that were relatively conserved previously. The results of this study demonstrate the continuous circulation and unique evolution of TMUV in mosquitoes in Yunnan province and suggest that appropriate surveillance should be taken.

Goose astroviruses (GoAstVs) are causative agents that account for fatal infection of goslings characterized by visceral urate deposition, resulting in severe economic losses in major goose-producing regions in China since 2017. In this study, we sought to unravel the intrinsic properties associated with adaptation and evolution in the host environment of GoAstVs. Consistent results from phylogenetic analysis and correspondence analysis performed on the codon usage patterns (CUPs) reveal 2 clusters of GoAstVs, namely, GoAstV-1 and GoAstV-2. However, multiple similar compositional characteristics were found, despite the high divergence between GoAstV-1 and GoAstV-2. Studies on the base composition of GoAstVs reveal an A/U bias, indicating a compositional constraint, while natural selection prevailed in determining the CUPs in the virus genome based on our neutrality plot analysis, reflecting high adaptive pressure to fit the host environment. Codon adaptation index (CAI) analysis revealed a higher degree of fitness to the CUPs of the corresponding host for GoAstVs than avian influenza virus and betacoronaviruses, which may be a favorable factor contributing to the high pathogenicity and wide distribution of GoAstVs in goslings. In addition, GoAstVs were less adapted to ducks and chickens, with significantly lower CAI values than to geese, which may be a reason for the different prevalence of GoAstVs among these species. Extensive investigations on dinucleotide distribution revealed a significant suppression of the CpG and UpA motifs in the virus genome, which may facilitate adaptation to the host's innate immune system by evading surveillance. In addition, our study reported the trends of increasing fitness to the host's microenvironment for GoAstVs through increasing adaptation to host CUPs and ongoing reduction of CpG motifs in the virus genome. The present analysis deepens our understanding of the basic biology, pathogenesis, adaptation and evolutionary pattern of GoAstVs, and contributes to the development of novel antiviral strategies.

Abstract Background Japanese encephalitis (JE) is a vaccine-preventable mosquito-borne disease caused by infection with the Japanese encephalitis virus (JEV). G1, G3 and G5 JEV have been isolated in China, but the dominant genotype circulating in Chinese coastal areas remains unknown. Besides, the emergence of G5 JEV infection case in South Korea suggests a risk of G5 JEV transmission in epidemic areas. We search for G5 JEV infected case and try to understand which genotype of JEV was more relative to human Japanese encephalitis in coastal provinces of China. Methods In this study, we collected serum specimens of JE cases in three coastal provinces of China (Guangdong, Zhejiang and Shandong Province) from 2018 to 2020 and conducted JEV cross-neutralization test against genotype 1, 3 and 5 JEV. In the same serum specimen, if one neutralization antibody titer had a 4-fold difference with the other two, the case was considered infected by that genotype of JEV. Results The acute serum specimens of clinical reported JE cases were obtained for laboratory confirming from hospitals in Shandong (92 cases), Zhejiang (192 cases) and Guangdong (77 cases) of China from 2018 to 2020. 70 of total 361 serum specimens were laboratory confirmed JEV infection. 2 cases were confirmed infected by genotype 1 JEV, 32 cases were by genotype 3 JEV and 2 was by genotype 5 JEV. Conclusions The investigation found that there were genotype 1, 3 and 5 JEV infections in JE cases in coastal area of China from 2018 to 2020. Genotype 3 was the main infection genotype among JE cases who have the definite infection genotype, and the infection case caused by genotype 5 JEV was confirmed serologically in China.

目的 建立流行性乙型脑炎病毒(JEV)和西尼罗病毒(WNV)的双重微滴式数字PCR(ddPCR)检测方法.方法 基于已设计的JEV和WNV引物探针,建立JEV和WNV双重ddPCR检测反应体系,摸索检测的敏感性、特异性和可重复性,灵敏度与双重荧光定量PCR(qPCR)的每个反应管内荧光信号达到设定的阈值所经历的循环数(Ct)值做对比.结果 双重ddPCR检测反应体系对JEV和WNV的检测灵敏度均可达到102拷贝/μl,该方法的可重复性、特异性良好,未发现与登革病毒、基孔肯雅病毒、寨卡病毒、蜱传脑炎病毒以及人类基因组有交叉反应.结论 建立的双重ddPCR方法能敏感、特异检测JEV和WNV,为不同场景下这2种病毒的检测提供了解决方案.

Objective:This study contrasts the immune efficacy of the varicella zoster virus glycoprotein E (VZV gE)using Al/CpG combined adjuvants and AS01 adjuvant in BALB/c mice.Methods:BALB/c mice were immunized at 0 and 21 days respectively, and serum antibodies were detected using enzyme-linked immunosorbent assay. Detection of neutralizing antibodies in mouse serum using varicella zoster virus; enzyme-linked immunosorbent spot assay was used to detect cellular immune response.Results:Following two intramuscular immunizations, mice in the experimental groups (Shingrix, gE+ Al/CpG, and gE+ AS01) demonstrated elevated neutralizing antibody titers and an augmented count of lymphocytes releasing IFN-γ and IL-4. The gE+ Al/CpG group displayed the highest neutralizing antibody titer (1943), yet the AS01-adjuvanted groups (Shingrix and gE+ AS01) showed increased lymphocyte counts secreting IFN-γ and IL-4 compared to the Al/CpG group (gE+ Al/CpG). In comparison to the AS01 adjuvant, Al/CpG adjuvants triggered a humoral immune response favoring Th2 in mice. The proportions of CD4 + T and CD8 + T cells were not significantly different among the experimental groups. Conclusions:Al/CpG adjuvant combined with gE protein resulted in high neutralizing antibody titers, while the intensity of the induced cellular immune response was inferior to that of AS01 adjuvant.

In recent years, numerous viruses have been identified from ticks, and some have been linked to clinical cases of emerging tick-borne diseases. Chinese northeast frontier is tick infested. However, there is a notable lack of systematic monitoring efforts to assess the viral composition in the area, leaving the ecological landscape of viruses carried by ticks not clear enough. Between April and June 2017, 7101 ticks were collected to perform virus surveillance on the China–North Korea border, specifically in Tonghua, Baishan, and Yanbian. A total of 2127 Ixodes persulcatus were identified. Further investigation revealed the diversity of tick-borne viruses by transcriptome sequencing of Ixodes persulcatus. All ticks tested negative for tick-borne encephalitis virus. Transcriptome sequencing expanded 121 genomic sequence data of 12 different virus species from Ixodes persulcatus. Notably, a new segmented flavivirus, named Baishan Forest Tick Virus, were identified, closely related to Alongshan virus and Harz mountain virus. Therefore, this new virus may pose a potential threat to humans. Furthermore, the study revealed the existence of seven emerging tick-borne viruses dating back to 2017. These previously identified viruses included Mudanjiang phlebovirus, Onega tick phlebovirus, Sara tick phlebovirus, Yichun mivirus, and three unnamed viruses (one belonging to the Peribunyaviridae family and the other two belonging to the Phenuiviridae family). The existence of these emerging tick-borne viruses in tick samples collected in 2017 suggests that their history may extend further than previously recognized. This study provides invaluable insights into the virome of Ixodes persulcatus in the China–North Korea border region, enhancing our ongoing efforts to manage the risks associated with tick-borne viruses.

Early gut microbial colonization is important for postnatal growth and immune development of the chicken. However, at present, commercial chickens are hatched and raised without adult hens, thus are cut off from the microbiota transfer between hens and chicks. In this study, we compared the gut microbiota composition between hen-reared and separately reared chicks, and its impact on the resistance to H9N2 avian influenza virus, with the motive of investigating the impact of this cutoff in microbiota transfer. We used the 16SrRNA sequencing method to assess the composition of the gut microbiota in chicks represented by three hen-reared groups and one separately reared group. We found that the diversity of gut microbes in the chicks from the three hen-reared groups was more abundant than in the separately reared group, both at the phylum and genus levels. Our findings highlight the importance of early parental care in influencing the establishment of gut microbiota in the early life of chicks. SourceTracker analysis showed that the feather and cloaca microbiota of hens are the main sources of gut microbiota of chicks. After H9N2 exposure, the viral infection lasted longer in the separately reared chicks, with the viral titers in their oropharyngeal swabs being higher compared to the hen-reared chicks at day 5 post-infection. Interestingly, our results revealed that the gut microbiota of the hen-reared chicks was more stable after H9N2 infection in comparison to that of the separately reared chicks. Microbiota transfer between the hens and their chicks promotes the establishment of a balanced and diverse microbiota in the early life of the chicks and improves microbiota stability after H9N2 challenge. These findings advance our understanding of the protective role of gut microbiota in the early life of chicks and should be instrumental in improving chick rearing in the commercial poultry industry.

Since its first isolation in around 2007, the avian-origin H3N2 canine influenza virus (CIV) has become established and continues to circulate in dog populations. This virus serves as a useful model for deciphering the complex evolutionary process of interspecies transmission of influenza A virus (IAV) from one species to its subsequent circulation in another mammalian host. The present investigation is a comprehensive effort to identify and characterize genetic changes that accumulated in the avian-origin H3N2 CIV during its circulation in the dog. We revealed that H3N2 CIV experiences greater selection pressure with extremely high global non-synonymous to synonymous substitution ratios per codon (dN/dS ratio) for each gene compared to the avian reservoir viruses. A total of 54 amino acid substitutions were observed to have accumulated and become fixed in the H3N2 CIV population based on our comprehensive codon-based frequency diagram analysis. Of these substitutions, 11 sites also display high prevalence in H3N8 CIV, indicating that convergent evolution has occurred on different lineages of CIV. Notably, six substitutions, including HA-G146S, M1-V15I, NS1-E227K, PA-C241Y, PB2-K251R, and PB2-G590S, have been reported to play imperative roles in facilitating the transmission and spillover of IAVs across species barriers. Most of these substitutions were found to have become fixed in around 2015, which might have been a favorable factor that facilitating the spread of these CIV lineages from South Asia to North America and subsequent further circulation in these areas. We also detected 12 sites in six viral genes with evidence for positive selection by comparing the rates of non-synonymous and synonymous substitutions at each site. Besides, our study reports trends of enhanced ongoing adaptation of H3N2 CIV to their respective host cellular systems, based on the codon adaptation index analysis, which points toward increasing fitness for efficient viral replication. In addition, a reduction in the abundance of the CpG motif, as evident from an analysis of relative dinucleotide abundance, may contribute to the successful evasion of host immune recognition. The present study provides key insights into the adaptive changes that have accumulated in the avian-origin H3N2 viral genomes during its establishment and circulation into dog populations.

Canine distemper virus (CDV) is a highly contagious virus that causes multi-systemic, sub-clinical to fatal diseases in a wide range of carnivore species. Based on the sequences of the haemagglutinin (H) gene, CDV strains have been classified into 18 major genetic lineages. In this study, we characterized the genomes of CDV isolated from the lungs of two dead red pandas in China. Histopathological and immunohistochemical analyses revealed damage due to viral infection in these lungs. The two strains showed a deep genetic distance from the other 18 recognized lineages (>4.6% at nucleotide level and >5.0% at amino acid level). The maximum clade credibility tree of the H- gene sequences showed that they belonged to an independent clade and had diverged a relatively long time ago from the Asia-4 lineage (since 1884). These results suggest that the analyzed strains belong to a new CDV lineage, which we designate as Asia-6. Our finding indicates that CDV infections in wildlife in China are complex and are a threat to endangered carnivores.

Recently, the phylogeographic patterns of African swine fever virus (ASFV) is studied in this journal. 1 Shen X. Pu Z. Li Y. Yu S. Guo F. Luo T. et al. Phylogeographic patterns of the African swine fever virus. J Infect. 2019; 79: 174-187 Abstract Full Text Full Text PDF Scopus (9) Google Scholar ASF possess a devastating threat to pig agriculture. Endemic to South and East Africa, ASFV has jumped out of Africa several times, with the most recent event being its introduction to Georgia in 2007 where it then spread through Russia and Eastern Europe. In August 2018, China reported its first ASF case in northeastern China. 2 Ge S. Li J. Fan X. Liu F. Li L. Wang Q. et al. Molecular characterization of African swine fever virus, China, 2018. Emerg Infect Dis. 2018; 24: 2131-2133 Crossref PubMed Scopus (198) Google Scholar Since then, it has quickly swept through China, and crossed borders to Vietnam, Cambodia, North Korea, and Mongolia. Effective preventive and biosafety measures can have a significant impact on limiting the spread of ASFV, but the low biosafety level of backyard farms, and weak veterinary infrastructure makes the eradication of this virus difficult. The long-term persistence of ASF in these countries, increases the risk of the spread of ASFV to other Southeast Asian countries and makes it imperative to improve our knowledge about this pathogen. Genotypes of ASFVs are based on its p72 gene, however, the p54 gene shows much higher diversity than p72. 1 Shen X. Pu Z. Li Y. Yu S. Guo F. Luo T. et al. Phylogeographic patterns of the African swine fever virus. J Infect. 2019; 79: 174-187 Abstract Full Text Full Text PDF Scopus (9) Google Scholar In addition, the phylogenetic positions of some viruses based on p54 is inconsistent with that deduced from p72, 3 Simulundu E. Chambaro H.M. Sinkala Y. Kajihara M. Ogawa H. Mori A. et al. Co-circulation of multiple genotypes of African swine fever viruses among domestic pigs in Zambia (2013–2015). Transbound Emerg Dis. 2018; 65: 114-122 Crossref PubMed Scopus (31) Google Scholar suggesting that recombination within this virus may occur. To examine this question, in this study, we collected all available ASFV genomes to investigate their genetic diversity and test for potential recombination events.

Recently, the emergence of African swine fever virus in China has raised great concern in this journal.1Shen X. Pu Z. Li Y. Yu S. Guo F. Luo T. et al.Phylogeographic patterns of the African swine fever virus.J Infect. 2019; 79: 174-187Abstract Full Text Full Text PDF Scopus (10) Google Scholar,2Li X. Xiao K. Zhang Z. Yang J. Wang R. Shen X. et al.The recombination hot spots and genetic diversity of the genomes of African swine fever viruses.J Infect. 2020; 80: 121-142Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar The epidemic is not over yet, outbreak of a new SARS-like Coronavirus in Wuhan at the end of 2019 poses new public health challenges in China. Coronaviruses are a large family of viruses that cause respiratory illnesses. Although Coronaviruses (CoVs) have been known for decades, they did not raise great attention in human medicine until the outbreaks of Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS).3Song Z. Xu Y. Bao L. Zhang L. Yu P. Qu Y. et al.From SARS to MERS, thrusting coronaviruses into the spotlight.Viruses. 2019; 11: E59Crossref PubMed Scopus (799) Google Scholar SARS-CoV first emerged in November 2002 in Guangdong province of Southern China and then rapidly spread to 29 countries and regions, infecting over 8000 individuals with a death toll of nearly 800.3Song Z. Xu Y. Bao L. Zhang L. Yu P. Qu Y. et al.From SARS to MERS, thrusting coronaviruses into the spotlight.Viruses. 2019; 11: E59Crossref PubMed Scopus (799) Google Scholar Ten years after the SARS, MERS emerged in 2012, have caused 2494 human infections with 858 deaths (as of November 2019) and remains a disease of global, and particularly Middle Eastern, public health concern. In 2017, a novel HKU2-related bat coronavirus, swine acute diarrhea syndrome coronavirus (SADS-CoV), caused the death of 24,693 piglets,4Zhou P. Fan H. Lan T. Yang X.L. Shi W.F. Zhang W. et al.Fatal swine acute diarrhoea syndrome caused by an HKU2-related coronavirus of bat origin.Nature. 2018; 556: 255-258Crossref PubMed Scopus (483) Google Scholar,5Gong L. Li J. Zhou Q. Xu Z. Chen L. Zhang Y. et al.A new bat-HKU2-like coronavirus in swine, China, 2017.Emerg Infect Dis. 2017; 23: 1607Crossref Scopus (142) Google Scholar raising further concern about these coronavirus. In December 2019, a new coronavirus (2019-nCoV), which is about 70% similar to SARS-Cov, was discovered in the central Chinese city of Wuhan, with 545 cases in 25 provinces being diagnosed (Fig. 1A, January 22, 2020). According to the World Health Organization (https://www.who.int), in addition to mainland China, this virus has also been detected in Japan, Thailand, Republic of Korea and the United States in travelers from Wuhan. The number of confirmed cases has been gradually increasing (Fig. 1B), which might be partially due to recent the establishment of relevant detection methods, but, at the same time, could signal that there could be a quick expansion of the epidemic. The three basic elements required for an infectious disease epidemic are source of the infection, route of transmission, and susceptible hosts (humans). Eliminating the source of the infection and cutting off the transmission route are usually effective means to block the spread of an infectious diseases. The successful precedent of emergent CoV containment based on the elimination of the primary reservoir is SARS. Bats are suggested to be the reservoir hosts of SARS-CoVs.6Ge X.Y. Li J.L. Yang X.L. Chmura A.A. Zhu G. Epstein J.H. et al.Isolation and characterization of a bat SARS-like coronavirus that uses the ACE2 receptor.Nature. 2013; 503: 535-538Crossref PubMed Scopus (1243) Google Scholar,7Li W. Shi Z. Yu M. Ren W. Smith C. Epstein J.H. et al.Bats are natural reservoirs of SARS-Like coronaviruses.Science. 2005; 310: 676-679Crossref PubMed Scopus (1845) Google Scholar However, without an intermediary host, bat derived CoVs cannot directly infect humans. The Carnivora–intermediate amplifying host (civets) of SARS-CoVs was found.8Guan Y. Zheng B.J. He Y.Q. Liu X.L. Zhuang Z.X. Cheung C.L. et al.Isolation and characterization of viruses related to the SARS coronavirus from animals in southern China.Science. 2003; 302: 276-278Crossref PubMed Scopus (1813) Google Scholar The quick control of the intermediate amplifying host by banning wild animal trade was the key factor in the effective control of SARS. Many of the 2019-nCoV infected people had either worked at or frequently visited a seafood market in Wuhan. Apart from fish, the market also sold other live wild animals – sparking concerns that the virus might have been transmitted from an animal to humans, just like SARS and MERS. The Wuhan CoVs cluster with SARS/SARS-like coronaviruses, and have about 70% overall genome sequence similarity. As this virus clusters with various bat Betacoronavirus, it is reasonable to deduce that bats are the native host for the 2019-nCov. However, its origin (source) remains unknown, that is, the animals that are the origin and amplifying hosts for this virus. This makes the elimination of this disease from the source difficult. The control of the route of transmission is another effective means of epidemic control. Infections of healthcare workers and family clusters suggest that 2019-nCoV has the ability to spread from human to human. Although the seafood market has been closed, the number of confirmed cases continues to gradually increase (Fig. 1B). This further supports the conclusion that this virus can spread by human-to-human contact. Previous research has shown that coronaviruses usually have an ability to rapidly mutate.9Woo P.C.Y. Huang Y. Lau S.K.P. Yuen K.-.Y. Coronavirus genomics and bioinformatics analysis.Viruses. 2010; 2: 1804-1820Crossref PubMed Scopus (561) Google Scholar We cannot exclude the possibility that some 2019-nCoVs will mutate to become "super-spreaders", as seen in SARS. Frequent disinfection of people-intensive places and animal trading markets should help stop the spread of the virus. Unfortunately, the outbreak has cast a shadow over the celebrations for the Lunar New Year, which falls on January 25. Millions of people in China travel over the course of the Spring Festival, both within the country and overseas. In addition, millions of college students (Wuhan has more than 1 million college students) will return to school after the winter vacation. This large-scale population migration could lead to further spread of this virus. Therefore, it is possible that this epidemic will be more serious after the Spring Festival. At present, the National Health Commission of China (http://www.nhc.gov.cn) has listed 2019-nCoV as Class B infectious disease and managed as Class A. Measures including the temperature monitoring of passengers at railway stations, airports, terminals and other transportation hubs have been carried out, which should slow the spread of the virus to a certain extent. However these disease control policies are far from enough, more strict methods to control population flow should be on the table. It is increasingly recognized that a One Health approach at the human–animal–ecosystem interface is needed for effective investigation, prevention and control of any emerging zoonotic disease. In the context of emerging zoonoses, human and veterinary medicine must work together. These viruses emerge from animal trading markets, where veterinary workers need to be vigilant and concerned whether these viruses have the potential to spread between animals and the impact the livestock industry. Veterinary workers should also actively invest in epidemiological investigations to find the natural hosts of these viruses and develop corresponding detection methods. Considering that the original source of the 2019-nCoV is very likely related to a wild animal, additional strict laws to limit wildlife markets should be made, otherwise, more emerging zoonoses from wild animals will occurred in the near future. This work was supported by the National Natural Science Foundation of China (Grant No. 31822056), Fund for the key program and Creative Research Group of the Department of Education of Guangdong Province, and the 111 Project (D20008).