Identification and phylogenetic analysis of Jingmen tick virus in Jiangxi Province, China

Jingmen tick virus (JMTV) is a newly identified segmented flavivirus that has been recognized in multiple hosts, such as humans, buffalos, bats, rodents, mosquitos and ticks. Various clinical cases and studies manifested that JMTV is a true arbovirus with wide host spectrum and showed potential threats toward public health. JMTV has been reported in multiple countries in Asia, Europe, Africa, and America. Moreover, wild boars serve as an important intermediary between humans and the wild ecological system. In China, it has been reported in nine provinces, while the prevalence and the distribution of JMTV in most regions including Jiangxi Province are still unknown. Thus, to profile the distribution of JMTV in Jiangxi Province, an epidemiological investigation was carried out from 2020 to 2022. In current study, 66 ticks were collected from 17 wild boars in Jiangxi Province. The results showed that 12 out of 66 ticks were JMTV positive, indicating JMTV is prevalent in ticks and boars in Jiangxi Province. The genome sequences of JMTV strain WY01 were sequenced to profile viral evolution of JMTV in China. Phylogenetic analysis divided JMTV strains into two genotypes, Group I and Group II. WY01 belongs to Group II and it shares the closest evolutionary relationship with the Japan strains rather than the strains from neighboring provinces in China suggesting that JMTV might have complex transmission routes. Overall, current study, for the first time, reported that JMTV is prevalent in Jiangxi Province and provided additional information concerning JMTV distribution and evolution in China.

Genomics evolution of Jingmen viruses associated with ticks and vertebrates

Jingmen virus (JMV) associated with ticks and vertebrates have been found to be related to human disease. We obtained the genome of a Jingmen tick virus (JMTV) strain from Rhipicephalus microplus in Guizhou province and compared the genomes of seven JMV species associated with ticks and vertebrates to understand the evolutionary relationships. The topology of the phylogenetic tree of segment 1 and segment 3 is similar, and segment 2 and segment 4 formed two different topologies, with the main differences being between Alongshan virus (ALSV), Takachi virus, Yanggou tick virus and Pteropus lylei jingmen virus (PLJV), and the possibility of genetic reassortment among these viruses. Moreover, we detected recombination within JMTV and between PLJV and ALSV. The genetic reassortment and recombination that occurs during cross-species transmission of these JMV associated with ticks and vertebrates not only complicates their evolutionary relationships, but also raises the risk of these viruses to humans.

Jingmen tick virus: an emerging arbovirus with a global threat

Jingmen tick virus (JMTV), belonging to the Flaviviridae family, is a novel segmented RNA virus identified in 2014 in the Jingmen region of Hubei Province, China. Up to now, JMTV has been detected in a variety of countries or regions in Asia, Europe, Africa, and the Americas, involving a wide range of arthropods and mammals, and even humans. The JMTV genome is composed of four linear RNA segments, two of which are derived from flaviviruses, while the other two segments are unique to JMTV and has no matching virus. Currently, JMTV has been shown to have a pathogenic effect on humans. Humans who had been infected would develop viremia and variable degrees of clinical symptoms. However, the pathogenic mechanism of JMTV has not been elucidated yet. Therefore, it is crucial to strengthen the epidemiological surveillance and laboratory studies of JMTV.

Molecular Detection of Tacheng Tick Virus-1 (TcTV-1) and Jingmen Tick Virus in Ticks Collected from Wildlife and Livestock in Turkey: First Indication of TcTV-1 Beyond China

Background: Jingmen tick virus (JMTV) and Tacheng tick virus-1 (TcTV-1) are emerging tick-borne viruses that have been recently confirmed to be etiological agents of human disease in China. However, the ecology of JMTV and TcTV-1, especially their association with ticks in wildlife and livestock, remains largely unknown in Turkey. Materials and Methods: Eight hundred thirty-two tick specimens in 117 pools were collected in Turkey between 2020 and 2022 from wildlife (Miniopterus schreibersii and Rhinolophus hipposideros; n = 10, 1.2%; Testudo graeca; n = 50, 6%) and livestock (Ovis aries and Capra aegagrus hircus; n = 772, 92.7%). The specimens were individually screened for JMTV and TcTV-1 using nRT-PCR assays targeting the partial genes. Results: JMTV was detected in one Ixodes simplex pool and two Rhipicephalus bursa pools collected from central and Aegean provinces, respectively. TcTV-1 was identified in five Hyalomma aegyptium pools collected in Mediterranean provinces. No coinfection was detected in the tick pools. Maximum likelihood analysis of JMTV partial segment 1 sequences reveal that these sequences form a separate cluster together with viruses previously characterized in Turkey and the Balkan Peninsula. The phylogenetic analysis of the TcTV-1 nucleocapsid sequences indicates that they are closely related to viruses in ticks, sheep, cattle, and humans in China, but form a separate group among themselves. Conclusion: This study provides the first molecular evidence of TcTV-1 in Hy. aegyptium in Turkey. In addion, these findings indicate that JMTV and TcTV-1 extend ticks species and geographic distributions. Thus, multiregional surveillance in livestock and wildlife is needed to evaluate potential tick vectors and the human health impact of these viruses in Turkey.

Identification and Characterization of Jingmen Tick Virus in Ticks from Yunnan Imported Cattle

Jingmen tick virus (JMTV) is a tick-borne segmented positive-sense ssRNA virus that can cause human disease. This virus has been confirmed to be widespread, having a wide host range. In human it can cause fever, headache, lymphadenopathy, and asthenia. Therefore, JMTV poses a threat to public health. In this study, we collected 478 ticks from imported cattle on three quarantine farms near the Yunnan border to detect medically significant tick-borne viruses. Our findings show that JMTV was the only detected virus, with an incidence rate of 56.67%. Phylogenetic analysis showed that our JMTV is more closely related to previously reported JMTV strains from Yunnan Province and neighboring Laos, implying that the tick-borne virus was most likely imported from Laos. In conclusion, we identified and characterized a novel JMTV strain in tick (Rhipicephalus microplus) from Yunnan imported cattle, emphasizing the importance of arbovirus quarantine of livestock imports.

Molecular evidence for potential transovarial transmission of Jingmen tick virus in Haemaphysalis longicornis fed on cattle from Yunnan Province, China

Jingmen tick virus (JMTV) is a novel tick-borne virus first identified from Jingmen city, Hubei Province of China in 2010. It has been proved that JMTV can cause human diseases and is widely distributed both inside and outside of China. However, the survival mode and transmission characteristics of JMTV still need further research, particularly in terms of transovarial transmission. In this study, an investigation was conducted to explore the presence of JMTV from engorged female ticks to their offspring. All engorged female adult ticks were collected from domestic cattle and allowed to lay eggs in appropriate humidity and temperature conditions. Maternal ticks, eggs and larvae were screened for JMTV RNA through real-time polymerase chain reaction (RT-PCR) and nested PCR methods. The results revealed the positive rate of 10.53% (10/95) in engorged ticks, 9.09% (2/22) in eggs and 8% (4/50) in larvae pools, respectively. Phylogenetic analysis confirmed that sequences from eggs and larvae had closer relationship with those isolates from maternal engorged ticks with more than 99.7% homology and JMTV manifested with evolutional conservatism. Our study has identified for the first time that JMTV could be transmitted from mother generation to offspring of Haemaphysalis Longicornis. Nonetheless, the efficiency of transovarial transmission in JMTV and the significance of ticks as amplification hosts still need to be further illustrated.

Identification of Jingmen tick virus (JMTV) in Amblyomma testudinarium from Fujian Province, southeastern China

Background

Jingmen tick virus (JMTV) is a newly discovered tick-borne virus that can cause disease in humans. This virus has been authenticated as being extremely widespread worldwide and as posing a significant threat to public health and safety.

Methods

We collected 35 ticks belonging to two tick species from wild boars in Nanping, Fujian Province, China. JMTV-specific genes were amplified by qRT-PCR and nested PCR to confirm the presence of this pathogen.

Results

More than one third of of all ticks collected (11/35) were positive for JMTV. Viral sequences were obtained from three of the JMTV-positive ticks, including the complete genomic sequence from one tick. This was the first time that JMTV was identified in the hard-bodied tick Amblyomma testudinarium. Phylogenetic analysis revealed that JMTV from Fujian Province shared > 90% identity with other isolates derived from China, but was distinct from those reported in France and Cambodia.

Conclusions

JMTV is characterized by relatively low mutations and has its own local adaptive characteristics in different regions. Our findings provide molecular evidence of the presence of JMTV in an overlooked tick species from an area not unrecognized as being endemic. They also suggest that JMTV occupies a wider geographical distribution than currently believed and is a potential disease vector.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05478-2.

Dermacentor silvarum, a Medically Important Tick, May Not Be a Competent Vector to Transmit Jingmen Tick Virus

Background: Jingmen tick virus (JMTV) has attracted great attention due to its potential pathogenicity in humans and its transmission by ticks. Dermacentor silvarum (D. silvarum) is one of the dominant tick species in northeastern China, and can transmit many pathogens to humans and animals. However, there have been no report of transmission of JMTV by D. silvarum. Materials and Methods: Ticks were collected from vegetation at the Aershan Port in Inner Mongolia in April 2019. And we do attempt to infect D. silvarum with JMTV by the immersion technique in laboratory conditions. The transmission of JMTV was examined by reverse transcriptase PCR, fluorescence in situ hybridization, and indirect immunofluorescence assay. Statistical analysis was performed using SPSS 24.0. Results: We found that JMTV may only be maintained in the tick without replication, and could not be transmitted to a host following transstadial transmission. Moreover, no virus colonization was found in the midgut or salivary glands of unfed D. silvarum; therefore, D. silvarum may not be susceptible to JMTV infection and therefore unlikely to carry and transmit JMTV. Conclusion: Our study has to some extent filled the knowledge gap regarding the possibility of JMTV transmission by a medically important tick vector, D. silvarum.

Several Tick-Borne Pathogenic Viruses in Circulation in Anatolia, Turkey

Introduction: We screened host-collected ticks for tick-borne viruses, including those recently documented as human pathogens. Methods: During 2020-2021, ticks removed form cattle, sheep, dogs, and cats in 11 provinces in 5 geographically distinct regions of Anatolia were identified, pooled, and screened using pan-nairovirus, pan-flavivirus and individual assays for Jingmen tick virus (JMTV), and Tacheng tick virus 1 and 2 (TcTV-1 and TcTV-2). Results: A total of 901 tick specimens, comprising 6 species were included. Rhipicephalus sanguineus complex was the most abundant species (44.1%), followed by Rhipicephalus bursa (38.3%), Haemaphysalis parva (7.2%), and others. The specimens were screened in 158 pools with 12 pools (7.6%) being positive. Crimean-Congo hemorrhagic fever virus (CCHFV) lineage Europe 2 (genotype VI) sequences were detected in R. bursa in five (3.2%) of the pools, with similar prevalences in central and Mediterranean Anatolian provinces. JMTV was identified in four R. bursa and one Rhipicephalus turanicus pools, collected from Mediterranean and southeastern Anatolia, with a CCHFV and JMTV coinfected R. bursa pool. The JMTV segment 1 sequences formed a separate cluster with those from Turkey and the Balkan peninsula in the maximum likelihood analysis. TcTV-2 was detected in two Dermacentor marginatus specimens (1.3%) collected in central Anatolia, with nucleocapsid sequences forming a phylogenetically segregated group among viruses from humans and ticks from China and Kazakhstan. Discussion: CCHFV Europe 2 was initially documented in ticks from central Anatolian locations, where related orthonairoviruses had been previously recorded. Ongoing activity and a wider distribution of JMTV and TcTV-2 were observed. These viruses should be screened as potential etiological agents in human infections associated with tick bites.

Detection of Jingmenviruses in Japan with Evidence of Vertical Transmission in Ticks

Jingmen tick virus (JMTV) and the related jingmenvirus-termed Alongshan virus are recognized as globally emerging human pathogenic tick-borne viruses. These viruses have been detected in various mammals and invertebrates, although their natural transmission cycles remain unknown. JMTV and a novel jingmenvirus, tentatively named Takachi virus (TAKV), have now been identified during a surveillance of tick-borne viruses in Japan. JMTV was shown to be distributed across extensive areas of Japan and has been detected repeatedly at the same collection sites over several years, suggesting viral circulation in natural transmission cycles in these areas. Interestingly, these jingmenviruses may exist in a host tick species-specific manner. Vertical transmission of the virus in host ticks in nature was also indicated by the presence of JMTV in unfed host-questing Amblyomma testudinarium larvae. Further epidemiological surveillance and etiological studies are necessary to assess the status and risk of jingmenvirus infection in Japan.

Uncovering the Worldwide Diversity and Evolution of the Virome of the Mosquitoes Aedes aegypti and Aedes albopictus

Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the Asian tiger mosquito, are the most significant vectors of dengue, Zika, and Chikungunya viruses globally. Studies examining host factors that control arbovirus transmission demonstrate that insect-specific viruses (ISVs) can modulate mosquitoes’ susceptibility to arbovirus infection in both in vivo and in vitro co-infection models. While research is ongoing to implicate individual ISVs as proviral or antiviral factors, we have a limited understanding of the composition and diversity of the Aedes virome. To address this gap, we used a meta-analysis approach to uncover virome diversity by analysing ~3000 available RNA sequencing libraries representing a worldwide geographic range for both mosquitoes. We identified ten novel viruses and previously characterised viruses, including mononegaviruses, orthomyxoviruses, negeviruses, and a novel bi-segmented negev-like group. Phylogenetic analysis suggests close relatedness to mosquito viruses implying likely insect host range except for one arbovirus, the multi-segmented Jingmen tick virus (Flaviviridae) in an Italian colony of Ae. albopictus. Individual mosquito transcriptomes revealed remarkable inter-host variation of ISVs within individuals from the same colony and heterogeneity between different laboratory strains. Additionally, we identified striking virus diversity in Wolbachia infected Aedes cell lines. This study expands our understanding of the virome of these important vectors. It provides a resource for further assessing the ecology, evolution, and interaction of ISVs with their mosquito hosts and the arboviruses they transmit.

Presence of Segmented Flavivirus Infections in North America

Identifying viruses in synanthropic animals is necessary for understanding the origin of many viruses that can infect human hosts and developing strategies to prevent new zoonotic infections. The white-footed mouse, Peromyscus leucopus, is one of the most abundant rodent species in the northeastern United States. We characterized the serum virome of 978 free-ranging P. leucopus mice caught in Pennsylvania. We identified many new viruses belonging to 26 different virus families. Among these viruses was a highly divergent segmented flavivirus whose genetic relatives were recently identified in ticks, mosquitoes, and vertebrates, including febrile humans. This novel flavi-like segmented virus was found in rodents and shares ˂70% aa identity with known viruses in the highly conserved region of the viral polymerase. Our data will enable researchers to develop molecular reagents to further characterize this virus and its relatives infecting other hosts and to curtail their spread, if necessary.

Geographical and Tick-Dependent Distribution of Flavi-Like Alongshan and Yanggou Tick Viruses in Russia

The genus Flavivirus includes related, unclassified segmented flavi-like viruses, two segments of which have homology with flavivirus RNA-dependent RNA polymerase NS5 and RNA helicase-protease NS3. This group includes such viruses as Jingmen tick virus, Alongshan virus, Yanggou tick virus and others. We detected the Yanggou tick virus in Dermacentor nuttalli and Dermacentor marginatus ticks in two neighbouring regions of Russia. The virus prevalence ranged from 0.5% to 8.0%. We detected RNA of the Alongshan virus in 44 individuals or pools of various tick species in eight regions of Russia. The virus prevalence ranged from 0.6% to 7.8%. We demonstrated the successful replication of the Yanggou tick virus and Alongshan virus in IRE/CTVM19 and HAE/CTVM8 tick cell lines without a cytopathic effect. According to the phylogenetic analysis, we divided the Alongshan virus into two groups: an Ixodes persulcatus group and an Ixodes ricinus group. In addition, the I. persulcatus group can be divided into European and Asian subgroups. We found amino acid signatures specific to the I. ricinus and I. persulcatus groups and also distinguished between the European and Asian subgroups of the I. persulcatus group.

Diversity and circulation of Jingmen tick virus in ticks and mammals

Since its initial identification in ticks in 2010, Jingmen tick virus (JMTV) has been described in cattle, rodents, and primates. To better understand the diversity, evolution, and transmission of JMTV, we sampled 215 ticks, 104 cattle bloods, 216 bats, and 119 rodents in Wenzhou city, Zhejiang Province, China as well as 240 bats from Guizhou and Henan Provinces. JMTV was identified in 107 ticks (from two species), 54 bats (eleven species), 8 rodents (three species), and 10 cattle, with prevalence levels of 49.8, 11.8, 6.7, and 9.6 per cent, respectively, suggesting that bats may be a natural reservoir of JMTV. Phylogenetic analyses revealed that all the newly identified JMTVs were closely related to each other and to previously described viruses. Additionally, all tick and mammalian JMTV sampled in Wenzhou shared a consistent genomic structure, suggesting that the virus can cocirculate between ticks and mammals without observable variation in genome organization. All JMTVs sampled globally could be divided into two phylogenetic groups, Mantel tests suggested that geographic isolation, rather than host species, may be the main driver of JMTV diversity. However, the exact geographical origin of JMTV was difficult to determine, suggesting that this virus has a complex evolutionary history.

Detection of novel tick-borne pathogen, Alongshan virus, in Ixodes ricinus ticks, south-eastern Finland, 2019

The newly identified tick-borne Alongshan virus (ALSV), a segmented Jingmen virus group flavivirus, was recently associated with human disease in China. We report the detection of ALSV RNA in Ixodes ricinus ticks in south-eastern Finland. Screening of sera from patients suspected for tick-borne encephalitis for Jingmen tick virus-like virus RNA and antibodies revealed no human cases. The presence of ALSV in common European ticks warrants further investigations on its role as a human pathogen.

Identification and characterization of Jingmen tick virus in rodents from Xinjiang, China

Jingmen tick virus (JMTV) is a recently identified virus which provides an unexpected connection between segmented and unsegmented RNA viruses. Recent investigations reveal that JMTV including JMTV-like virus (Alongshan virus) could be associated with human disease, suggesting the significance of JMTV in public health. To better understand the genetic diversity and host range of JMTV, a total of 164 rodents representing 8 species were collected in Qapqal Xibe county of Xinjiang Uygur Autonomous Region, China, and were screened for JMTVs using RT- PCR. Consequently, JMTV was identified in 42 rodents including 23 Microtus arvalis voles (24.5%), 9 Apodemus uralensis mice (29.0%), 5 Mus musculus mice, 1 Rhombomys opimus gerbil, 1 Meriones tamariscinus gerbil, 1 Meriones libycus gerbil, 1 Cricetulus migratorius hamster and 1 Microtus gregalis vole. Interestingly, nearly complete genome sequences were successfully recovered from 7 JMTV positive samples. Although the newly identified rodent JMTVs were closely related to those previously identified in ticks from China, based on the phylogenetic analysis of the S1, S2 and S3 segments, the newly identified rodent viruses clustered into two genetic groups. One group comprised of viruses only found in M. arvalis, while another group included viruses from A. uralensis, C. migratorius and M. gregalis. However, all rodent viruses clustered together in the S4 tree. Considering rodents live in close proximity to humans, more efforts are needed to investigate the role of rodents in the evolution and transmission of JMTV in nature.

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Jingmen tick virus (JMTV) was found in 8 species of rodents from Xinjiang of China.

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Two sub-lineages of JMTVs were co-circulating in these rodents in Xinjiang.

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One sub-lineage of viruses was only identified in Microtus arvalis voles.

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Our data indicate that rodents are one of the natural hosts of JMTV.

Isolation and Characterisation of Alongshan Virus in Russia

In recent decades, many new flavi-like viruses have been discovered predominantly in different invertebrates and, as was recently shown, some of them may cause disease in humans. The Jingmenvirus (JMV) group holds a special place among flaviviruses and flavi-like viruses because they have a segmented ssRNA(+) genome. We detected Alongshan virus (ALSV), which is a representative of the JMV group, in ten pools of adult Ixodes persulcatus ticks collected in two geographically-separated Russian regions. Three of the ten strains were isolated in the tick cell line IRE/CTVM19. One of the strains persisted in the IRE/CTVM19 cells without cytopathic effect for three years. Most ALSV virions purified from tick cells were spherical with a diameter of approximately 40.5 nm. In addition, we found smaller particles of approximately 13.1 nm in diameter. We obtained full genome sequences of all four segments of two of the isolated ALSV strains, and partial sequences of one segment from the third strain. Phylogenetic analysis on genome segment 2 of the JMV group clustered our novel strains with other ALSV strains. We found evidence for the existence of a novel upstream open reading frame in the glycoprotein-coding segment of ALSV and other members of the JMV group.

Proteomics Computational Analyses Suggest That the Envelope Glycoproteins of Segmented Jingmen Flavi-Like Viruses are Class II Viral Fusion Proteins (b-Penetrenes) with Mucin-Like Domains

Jingmen viruses are newly described segmented flavi-like viruses that have a worldwide distribution in ticks and have been associated with febrile illnesses in humans. Computational analyses were used to predict that Jingmen flavi-like virus glycoproteins have structural features of class II viral fusion proteins, including an ectodomain consisting of beta-sheets and short alpha-helices, a fusion peptide with interfacial hydrophobicity and a three-domain architecture. Jingmen flavi-like virus glycoproteins have a sequence enriched in serine, threonine, and proline at the amino terminus, which is a feature of mucin-like domains. Several of the serines and threonines are predicted be modified by the addition of O-linked glycans. Some of the glycoproteins are predicted to have an additional mucin-like domain located prior to the transmembrane anchor, whereas others are predicted to have a stem consisting of two alpha-helices. The flavivirus envelope protein and Jingmen flavi-virus glycoproteins may have diverged from a common class II precursor glycoprotein with a mucin-like domain or domains acquired after divergence.

Emergence of human infection with Jingmen tick virus in China: A retrospective study

Background

A tick-borne segmented RNA virus called Jingmen tick virus (JMTV) was recently identified, variants of which were detected in a non-human primate host and fatal patients with Crimean-Congo haemorrhagic fever. We investigated its infectivity and pathogenicity for humans.

Methods

We obtained skin-biopsy, blood and serum samples from patients with tick bites, and used high-throughput sequencing, in situ hybridisation, and serologic testing to diagnose and ascertain the cases of JMTV infection.

Findings

A JMTV strain was isolated from the tick Amblyomma javanense into an embryo-derived tick cell line. We obtained sustained passage of JMTV, and revealed that it was able to accumulate in salivary glands of experimentally infected ticks. Four JMTV-infected patients were identified by high-throughput sequencing of skin biopsies and blood samples. The virus replication in skin tissue was visualised by in situ hybridisation. The four patients all had an itchy or painful eschar at the site of tick bite, with or without lymphadenopathy. Immunohistochemical examination revealed remarkable local inflammation manifested as infiltration by neutrophils. Eight patients were identified by serological testing and showed more severe clinical manifestations. Two Ixodes persulcatus ticks detached from patients were positive for JMTV. All JMTV strains identified in this study formed a well-supported sub-lineage, distinct from those previously reported in China.

Interpretation

The public significance of JMTV should be highly concerning due to its potential pathogenicity for humans and efficient transmission by potential ticks.

Fund

China Natural Science Foundation, State Key Research Development Programme, and United Kingdom Biotechnology and Biological Sciences Research Council.