Aetiology of Tick-Borne Infections in an Adult Swedish Population—Are Co-Infections with Multiple Agents Common?

In Scandinavia, tick-borne infections affecting humans include Lyme borreliosis (LB), tick-borne encephalitis (TBE) and human granulocytic anaplasmosis (HGA). Each of these infections can present with unspecific symptoms. In this prospective clinical study, we recruited patients based on two independent inclusion criteria;1) patients with unspecific symptoms, i.e. fever (≥38.0℃) or a history of feverishness and/or any combination of headache, myalgia or arthralgia and 2) patients with erythema migrans (EM), following an observed tick bite or tick exposure within one month prior to onset of symptoms. A total of 206 patients fulfilled the study. Among these, we could identify 186 cases of LB (174 with EM), 18 confirmed and two probable cases of HGA and two cases of TBE. Thirteen of the HGA cases presented without fever. Furthermore, 22 of the EM patients had a sub-clinical co-infection with Anaplasma phagocytophilum, based on serology. Both TBE cases had co-infections, one with Borrelia burgdorferi and one with Anaplasma phagocytophilum. We conclude that it is important to consider several causative agents and possible co-infections in the clinical management of infectious diseases where ticks may be suspected as vectors.

New tools,new tick-borne diseases?

Tick-borne diseases(TBDs) are a major public health concern that has increased in the past three decades. Nevertheless, emerging or reemerging TBDs may be still misdiagnosed. Molecular biology techniques for the screening of ticks, use of "Omics" approaches and the incorporation of analytical methods such as mass spectrometry or nuclear magnetic resonance, to the study of ticks and their associated pathogens or potential pathogens are promising tools for a more accurate differential diagnosis of TBDs. However, this huge amount of data needs to be carefully interpreted before being incorporated to the routine of clinical practice. In the meantime, a clinical approach and high level of suspicion keep being essential for the diagnosis and proper handling of TBDs.

Tick-borne encephalitis: A review of epidemiology, clinical characteristics, and management

Tick-borne encephalitis is an infection of central nervous system caused by tick-borne encephalitis virus transmitted to humans predominantly by tick bites. During the last few decades the incidence of the disease has been increasing and poses a growing health problem in almost all endemic European and Asian countries. Most cases occur during the highest period of tick activity, in Central Europe mainly from April to November. Tickborne encephalitis is more common in adults than in children. Clinical spectrum of the disease ranges from mild meningitis to severe meningoencephalitis with or without paralysis. Rare clinical manifestations are an abortive form of the disease and a chronic progressive form. A post-encephalitic syndrome, causing long-lasting morbidity that often affects the quality of life develops in up to 50% of patients after acute tick-borne encephalitis. Clinical course and outcome vary by subtype of tick-borne encephalitis virus(the disease caused by the European subtype has milder course and better outcome than the disease caused by Siberian and Far-Easter subtypes), age of patients(increasing age is associated with less favorable outcome), and host genetic factors. Since clinical features and laboratory results of blood and cerebrospinal fluid are nonspecific, the diagnosis must be confirmed by microbiologic findings. The routine laboratory confirmation of the tick-borne encephalitis virus infection is based mainly on the detection of specific Ig M and Ig G antibodies in serum(and cerebrospinal fluid), usually by enzyme-linked immunosorbent assay. There is no specific antiviral treatment for tick-borne encephalitis. Vaccination can effectively prevent the disease and is indicated for persons living in or visiting tick-borne encephalitis endemic areas.

Molecular Detection of Tick-borne Pathogens in Ticks Collected from Hainan Island,China

Pathogens like bacteria and protozoa,which affect human and animal health worldwide,can be transmitted by vectors like ticks.To investigate the epidemiology and genetic diversity of bacteria and protozoans carried by ticks in Chengmai county of Hainan province,China,285 adult hard ticks belonging to two species[Rhipicephalus sanguineus(sensu lato):183,64.21%and Rhipicephalus microplus:102,35.79%]from dogs,cattle,and goats were collected.Microbial families were identified in these ticks by amplifying the 18 S r RNA,16 S r RNA(rrs),citrate synthase(glt A),and heat shock protein(gro EL)genes.Our data revealed the presence of four recognized species and two Candidatus spp.of Anaplasmataceae and Coxiellaceae.In sum,these data reveal an extensive diversity of Anaplasmataceae bacteria,Coxiellaceae bacteria,Babesiidae,and Hepatozoidae in ticks from Hainan Island,highlighting the need to understand the tickborne pathogen infection in local animals and humans.

Molecular survey of tick-borne pathogens in Ixodid ticks collected from hunted wild animals in Tuscany, Italy

Objective: To determine the prevalence of zoonotic tick-borne bacteria in feeding ticks removed from hunted wild animals. Methods: PCR was executed on DNA extracted from 77 tick pools to detect Anaplasma phagocytophilum, Bartonella spp., Borrelia burgdorferi sensu lato, Coxiella burnetii and Rickettsia spp. Results: A total of 432 ticks were collected: 30(6.94%) Haemaphysalis punctata, 72(16.7%) Dermacentor marginatus and 330(76.38%) Ixodes ricinus. For each animal one or two pools of 3 ticks of the same species was constituted. Seventy-seven tick pools were examined by PCR: 58(75.32%) resulted infected and among them 14(18.18%) showed co-infections. In particular, 29(37.66%) pools were positive for Bartonella spp., 23(29.87%) for Anaplasma phagocytophilum, 16(20.78%) for Rickettsia spp., and 5(6.49%) for Borrelia burgdorferi s.l. All samples were negative for Coxiella burnetii. Conclusions: The results demonstrate the presence of several zoonotic tick-borne pathogens in the studied area, and underline the risk of exposure to infections for hunters not only during the outdoor activity, but also when they manipulate hunted animals infested by infected ticks.

Tick-borne pathogens in Iran:A meta-analysis

Objective:Different studies have been performed on the prevalence of tick-borne pathogens in different areas of Iran;however,as far as our knowledge,there is no regional meta-analysis available for consideration and estimation of tick species infected with different pathogens in Iran.Methods:In this review,among different databases,a total of 95 publications were included,and the infection of different tick species to different tick-borne pathogens was determined;furthermore,presence of pathogens(with 95%confidence intervals)in tick vectors was calculated separately for each province,using Comprehensive Meta-Analysis version 2(Biostat,USA).Results:Totally,among all 95 studies,5673 out of 33521 investigated ticks were positive according to different detection methods.Overall estimated presence of pathogens in tick vectors in Iran was 8.6%(95%CI 7.0%-10.6%,P<0.001).Of all 46 species of ticks in 10 genera in Iran,28 species in 9 genera,including Alveonasus,Argas,Boophilus,Dermacentor,Haemaphysalis,Hyalomma,Ixodes,Ornithodoros,and Rhipicephalus were infected with at least 20 pathogens in 10 genera including Aegyptianella,Anaplasma,Babesia,Borrelia,Brucella,Orthonairovirus[CrimeanCongo hemorrhagic fever virus(CCHFV)],Coxiella,Ehrlichia,Rickettsia and Theileria in 26 provinces of Iran.The presence of pathogens in ticks collected in western Iran was more than other regions.Hyalomma anatolicum(20.35%),Rhipicephalus sanguineus(15.00%),and Rhipicephalus bursa(14.08%)were the most prevalent infected ticks for different pathogens.In addition,most literatures were related to CCHFV and Theileria/Babesia spp.Conclusions:Public health and veterinary professionals should be aware of diagnosing possible diseases or outbreaks in vertebrates.

Identification of tick-borne pathogens using metagenomic analyses in H.longicornis feeding on humans in downtown Beijing

On August 14th,2018,a Beijing resident living in Xicheng District found a female H.longicornis tick attached to the skin at the front of his upper shin.On examination,the patient was afebrile and appeared well.The species of the tick was identified through morphological characteristics and phylogenetic analysis based on cytochrome C oxidase subunit I.This H.longicornis tick was screened for tick-borne pathogens such as viruses,bacteria and parasites.RNA pathogens were screened by PCR and sequencing,while DNA pathogens were screened by metagenomic analyses.It was found that the tick was positive for the DNA sequences of zoonotic and animal pathogens such as A phagocytophilum,Ehrlichia minasensis and C.burnetii.Considering the good health condition of the patient,we hypothesized that the pathogens originated from the tick specimen itself rather than host blood meal.For the first time,our study reveals the possible risk of transmission of tick-borne pathogens to human beings through tick bit in downtown Beijing.Further research is needed to screen for tick-borne pathogens among unfed ticks collected from central Beijing.

Genetically engineered bacterial-like particles induced specific cellular and humoral immunity as effective tick-borne encephalitis virus vaccine

Tick-borne encephalitis(TBE)is a natural focal disease with fatal encephalitis induced by tick-borne encephalitis virus(TBEV),seriously threatening human and public health.Protection of TBE depends on vaccination with inactivated vaccine,which requires high cost and multiple immunizations.Here,we construct genetically engineered bacterial-like particles(BLPs)as an effective TBEV vaccine with simplified immunizations and improved immune efficacy.The TBEV BLPs involve the combination of the gram-positive enhancer matrix from Lactococcus lactis,and TBEV envelope(E)protein expressed by genetically engineered recombinant baculovirus.The prepared TBEV BLPs can effectively stimulate the activation of dendritic cells to present the TBEV E proteins to T and B cells,leading to strong and durable cellular and humoral immune responses in mice.Surprisingly,the serum levels of specific IgG antibodies in mice remain about 10^(6)at 6 months after the secondary immunization.Overall,the TBEV BLPs can be used as a potent vaccine candidate,laying the foundation for developing novel TBEV genetically engineered vaccines.

Development of a novel virus-like particle-based vaccine for preventing tick-borne encephalitis virus infection

Tick-borne encephalitis virus(TBEV)is an important tick-borne pathogen that poses as a serious public health concern.The coverage and immunogenicity of the currently available vaccines against TBEV are relatively low;therefore,it is crucial to develop novel and effective vaccines against TBEV.The present study describes a novel strategy for the assembly of virus-like particles(VLPs)by co-expressing the structural(core/prM/E)and non-structural(NS2B/NS3Pro)proteins of TBEV.The efficacy of the VLPs was subsequently evaluated in C57BL/6 mice,and the resultant IgG serum could neutralize both Far-Eastern and European subtypes of TBEV.These findings indicated that the VLP-based vaccine elicited the production of cross-subtype reactive antibodies.The VLPs provided protection to mice lacking the type I interferon receptor(IFNAR^(-/-))against lethal TBEV challenge,with undetectable viral load in brain and intestinal tissues.Furthermore,the group that received the VLP vaccine did not exhibit significant pathological changes and the inflammatory factors were significantly suppressed compared to the control group.Immunization with the VLP vaccine induced the production of multiple-cytokine-producing antiviral CD4+T cells in vivo,including TNF-α^(+),IL-2^(+),and IFN-γ^(+)T cells.Altogether,the findings suggest that noninfectious VLPs can serve as a potentially safe and effective vaccine candidate against diverse subtypes of TBEV.

Recovery of a Far-Eastern Strain of Tick-Borne Encephalitis Virus with a Full-Length Infectious cDNA Clone

Tick-borne encephalitis virus(TBEV) is a pathogenic virus known to cause central nervous system(CNS) diseases in humans, and has become an increasing public health threat nowadays. The rates of TBEV infection in the endemic countries are increasing. However, there is no effective antiviral against the disease. This underscores the urgent need for tools to study the emergence and pathogenesis of TBEV and to accelerate the development of vaccines and antivirals. In this study, we reported an infectious c DNA clone of TBEV that was isolated in China(the WH2012 strain). A beta-globin intron was inserted in the coding region of nonstructural protein 1(NS1) gene to improve the stability of viral genome in bacteria. In mammalian cells, the inserted intron was excised and spliced precisely, which did not lead to the generation of inserted mutants. High titers of infectious progeny viruses were generated after the transfection of the infectious clone. The cDNA-derived TBEV replicated efficiently, and caused typical cytopathic effect(CPE) and plaques in BHK-21 cells. In addition, the CPE and growth curve of cDNA-derived virus were similar to that of its parental isolate in cells. Together, we have constructed the first infectious TBEV cDNA clone in China, and the clone can be used to investigate the genetic determinants of TBEV virulence and disease pathogenesis, and to develop countermeasures against the virus.

Molecular evidence and phylogenetic delineation of spotted fever group Rickettsia species in Amblyomma ticks from cattle in Gauteng and Limpopo Provinces,South Africa

Objective:To determine the prevalence of tick-borne pathogens with a particular focus on Rickettsia spp.in ticks collected from cattle in Gauteng and Limpopo Provinces,South Africa.Methods:A total of 200 ticks were collected from cattle within the Madala livestock,Pretoria,Gauteng Province and in Mankweng Township,Polokwane,Limpopo Province in 2019.The ticks were morphologically identified and processed individually for a total genomic DNA extraction.Specific primers targetting ompA,ompB,and the 17KDa genes were used for a molecular screening and delineation of Rickettsia from the extracted genetic materials using polymerase chain reaction(PCR)technique.PCR amplicons of positive samples were sequenced bidirectionally using the Sanger sequencing method.Sequences generated were processed and analysed using appropriate bioinformatics software.Results:The ticks were morphologically identified as Amblyomma spp.PCR profiling of the genomic DNA samples revealed the presence of the Rickettsia pathogen in 42(21%)of the ticks collected from both Provinces.Out of the genes profiled,14(7%)were positive for 17KDa,42(21%)for ompA and 32(16%)were positive for ompB genes respectively.The nucleotide blast of the sequenced genomes showed high similarity,as high as 100% with other reference Rickettsia(R.)africae in the GenBank.The phylogenetic analysis of the sequences further validated them as R.africae with their characteristic clustering pattern with related reference sequences.Conclusions:There is an abundance of R.africae in Amblyomma ticks collected from cattle in the study areas.This has serious public health implications as individuals who accidentally get infested with the ticks could acquire R.africae.Hence,adequate precautions in terms of sensitization of farmers about the risk and mass mobilization drive to control the vectors in the areas are highly recommended to safeguard public health.

Infection related membranoproliferative glomerulonephritis secondary to anaplasmosis:A case

BACKGROUND Anaplasmosis is a tick-borne disease with a range of clinical manifestations,from a flu-like illness with fever and myalgias to a severe systemic disease with multisystem organ failure.Although renal involvement is not a common presentation,there have been few cases reporting acute kidney injury from Anaplasmosis.CASE SUMMARY We present a 55-year-old female with anaplasmosis who developed acute kidney injury due to membranoproliferative glomerulonephritis(MPGN).The patient originally presented with cough and shortness of breath.She was admitted to the hospital with a diagnosis of community acquired pneumonia and received antibiotics.During the hospital course she developed severe acute renal failure.Initial serological work up didn’t provide any conclusive diagnosis.Hence,she underwent kidney biopsy which showed MPGN pattern suggesting autoimmune,multiple myeloma or infectious etiology.Extensive work up was undertaken which was negative for autoimmune diseases,vasculitis panel,paraproteinemias but tested positive for IgG anaplasma with high titers indicating Anaplasmosis.CONCLUSION Our case shows a unique presentation of severe acute renal failure from MPGN from tick borne illness.MPGN is usually seen with autoimmune diseases,hepatitis C virus infections,paraproteinemias.Hence,we suggest that tick borne illness should also be considered when evaluating acute renal failure cases in tick borne prevalent regions.

Inhibition of <i>Ehrlichia canis</i>and <i>Babesia canis</i>transmission among ticks fed together on dogs vaccinated with Bm86 antigen

GAVAC (Heber Biotec S.A, Havana, Cuba) is a commercially available vaccine developed with the Rhipicephalus (Boophilus) microplus Bm86 recombinant antigen. Bm86 is a “concealed” antigen that is present in the plasmatic membrane of tick gut epithelial cells with unknown function so far. It is well known that after vaccination in the last fifteen years in Cuba, there was a significant decrease of babesiosis (Babesia bovis and Babesia bigemina) and anaplasmosis (Anaplasma marginale) in cattle. A reduced transmission capacity of ticks fed on tick-immune animals and humans has been reported for several tick-borne pathogens. Recent experiments have demonstrated that an anti-tick vaccine may contribute to the control of tick-borne pathogens not only by decreasing the exposure of susceptible hosts to ticks, but also by reducing the vector capacity of ticks. In this study, the potential of Bm86 vaccination to interfere with pathogen transmission among ticks was evaluated by using as experimental model the brown dog tick Rhipicephalus sanguineus and the tickborne Babesia canis and Ehrlichia canis pathogens. Dogs, vaccinated and not vaccinated, were infested with pathogen-infected ticks and noninfected nymphs of R. sanguineus. After feeding, the pathogen transmission to newly molted adults from co-feeding uninfected nymphs was studied by conventional PCR and qPCR. Results suggest that the anti-Bm86 antibodies could be able to block the transmission of B. canis and/or E. canis from infected to non-infected ticks.

Molecular survey on zoonotic tick—borne bacteria and chlamydiae in feral pigeons(Columba livia domestica)

Objective;To determine the presence of zoonotic tick-borne bacteria in feral pigeons(Columba lixia domestica) from urban areas.Methods:Spleen samples from 84 feral pigeons,found dead with traumatic injuries in urban areas,were examined by PCR to detect DNA of Anaplasma phagocytophilum,Bartonella spp.,Borrelia burgdorferi sensu lato.Coxiella burnetii.Rickettsia spp.,and Chlamydnphila spp.Results:Twenty(23.8%) pigeons were infected by tick-borne agents,in particular 2(2.38%) animals resulted positive for Bartonella spp.,5(5.95%) for Coxiella burnetii.5(5.95%) for Rickettsia spp.,13(15.47%) for Borrelia burgdorferi sensu lato.All birds scored negative for anaplasma phagocytophilum.Moreover,17(20.23%) pigeons were positive for Chlamydophila spp.and among them 10(11.9%) for Chlamydophila psittaci,Mixed infections by two or three agents were detected in 8(9.52%) animals.Conclusions:Feral pigeons living in urban and periurban areas are a hazard for the human health as source of several pathogens.The obtained results confirm pigeons as reservoirs of chlamydial agents and suggest that they may be involved in the epidemiology of zoonotic tick-borne infections too.

Are There Undiagnosed TBE-, Herpes- or Enteroviral Infections among Children Being Evaluated for Lyme Neuroborreliosis?

Lyme neuroborreliosis (LNB) in children is a challenging diagnosis based on clinical manifestations and laboratory findings. The aim of this study was to investigate whether herpes simplex virus (HSV) 1 or 2, varicella zoster virus (VZV), enterovirus or tick-borne encephalitis virus (TBEV) could be identified in cerebrospinal fluid (CSF) or serum from children being evaluated for LNB, in order to elucidate whether such infectious diseases may be missed by the clinician. Methods: Ninety-nine pediatric patients (n = 99) were retrospectively included from a previous study on LNB in southeast of Sweden. They had been diagnosed as “Possible LNB” or “Not determined” due to negative Borrelia antibody index in CSF. Routine polymerase chain reaction (PCR) methods were used for detection of herpes viral RNA or enteroviral DNA in CSF. An ELISA assay was used for detection of anti-TBEV antibodies (IgM and IgG) in serum. Results: One patient showed elevated anti-TBEV IgM and IgG antibodies in serum, indicating a current TBE infection. No positive PCR reactions for HSV 1 or 2, VZV or enterovirus were detected in CSF from any of the patients. In conclusion, our results suggest that undiagnosed herpes- or enteroviral infections are unlikely to explain CNS symptoms in children being evaluated for LNB, whereas missed TBE infections may occur. TBEV serology should be included when evaluating children for LNB in TBE endemic areas.

PathoDNA, an Advanced Diagnostic for Lyme Disease &Co-Infections Utilizing Next Generation DNA Sequencing with Greater Sensitivity and Selectivity than ELISA/Western Blot

The controversial subject of chronic Lyme disease has occupied medical discourse for years while contributing to unprecedented patient suffering in the United States and abroad. A general misunderstanding of Lyme disease and overconfidence in the Center for Disease Control’s (CDC) recommended two-step test for Lyme disease has led to misdiagnosis and incorrect treatment over the years. This leads to increasing medical expenses and worse outcomes for patients. The two-step test, an ELISA immunoblot followed by a confirmatory Western blot, yields accuracy rates as low as 29% for acute Lyme disease and 75% for chronic Lyme disease. While these practices have been a staple of microbiology for decades, these accuracy rates are unacceptable for diagnostic tests when better technology is available. PathoDNA, a Next-Generation DNA sequencing test for Lyme disease and other tick-borne pathogens, achieves accuracy rates of 98% for B. burgdorferi and 95% or greater for other common tick-borne pathogens with superior sensitivity and selectivity. PathoDNA is a Clinical Laboratory Improvement and Amendments (CLIA)-validated laboratory test that achieves these results utilizing Next Generational DNA Sequencing and a proprietary bioinformatics database. Thus, it allows for rapid results and specific identification of tick-borne illnesses. In this article, we will compare this promising technology against the existing standards for diagnosing and testing Lyme disease. We believe that PathoDNA can set a new standard for identifying Borrelia and diagnosing Lyme disease along with other tick-borne infections.

Dissociating Delusional Disorders and Infections from Dermatologic and Neurologic Effects of Morgellons Disease

Morgellons disease (MD) is a multi-system disorder characterized by multicolor filaments extruding out of the skin along with an array of dermatologic and neuropsychiatric symptoms. It was previously termed Delusional parasitosis. However, published scientific data found the association of MD symptoms with the systemic manifestations of Lyme disease, caused by Borrelia spirochete. In a retrospective study of 122 MD patients, skin specimens were examined and 96% of them showed Borrelia spirochete in their histology sample. Hence, this association suggests that spirochete infection could be a possible cause of chronic illness in MD patients, and this rejected the physician’s perception that MD lesions might be self-inflicted. A cohort study reported tick-borne co-infections among MD patients, which could also be an etiological factor for dermopathy in MD patients. Some literature also discussed neuropsychiatric manifestations like cognitive impairment, dementia anxiety, depression, paranoia, and sensory hallucinations in Lyme disease and associated tick-borne infection. The objectives of this review are to identify the differences in the past and current perception regarding the pathogenesis of MD and determine the associations of spirochetal and tick-borne diseases with MD and psychiatric illnesses. More than 50 new research articles and case reports were reviewed and only 31 articles were shortlisted and used as references. This review has a detailed discussion on Morgellons disease and its association with Spirochete infection.

Bacteriome in Ticks Collected from Domestic Livestock in Kenya

Background: Metagenomics approaches are increasingly being utilized as “dipstick” for microbial carriage. In this study, 16S rRNA metagenomics was used to probe for microbial community that resides in the ticks, those they pick from the environment, wildlife and livestock and to identify potential tick borne zoonoses. Methods: Tick DNA from 463 tick pools collected from domestic animals between 2007 and 2008 were amplified with primers that target the 16S rRNA V3-V4 domain and then sequenced on Illumina Miseq platform using 300 cycles version 3 kits. Ticks were pooled according to species and animal from which they were collected. A non-target control was used to track laboratory contaminants. Sequence data were analyzed using Mothur v1.3 pipeline and R v3.3.1 software and taxonomy determined using SILVA rRNA database. Shannon diversity index was used to compute bacterial diversity in each tick species before computing the means. Results: A total of 645 bacteria genera grouped into 27 phyla were identified. Four phyla contributed 97.4% of the 36,973,934 total sequences. Proteobacteria contributed 61.2% of these sequences that tarried to 33.8% genera, compared to 15.9% (23.4% genera) for Firmicutes, 15.6% (20% genera) for Actinobacteria and 4.7% (11.6% genera) for Bacteroidetes. The remaining 23 phyla only contributed 2.6% of the sequence reads (11.2% genera). Amongst the 645 genera, three groups were discernible, with the biggest group comprised commensals/symbionts that contributed 93.6% of the genera, but their individual sequence contribution was very low. Group two comprised genera that are known to contain pathogenic species, with Coxiella contributing 15,445,204 (41.8%) sequences, Corynebacterium (13.6%), Acinetobacter (4.3%), Staphylococcus (3.9%), Bacillus (2.7%) and Porphyromonas (1.6%), Ralstonia (1.5%), Streptococcus (1.3%), Moraxella (1.3%), amongst others. Group three comprised genera known to contain tick borne zoonotic pathogens (TBZ): Rickettsiae, Anaplasma, Francisella, Ehrlichia, Bartonella and Borrelia. Individually the TBZ contributed Amblyomma variegatum carried the least diverse bacteria (mean Shannon diversity index of 2.69 ± 0.92) compared to 3.79 ± 1.10 for A. gemma, 3.71 ± 1.32 for A. hebraeum, 4.15 ± 1.08 for other Amblyomma spp, 3.79 ± 1.37 for Hyalomma truncatum, 3.67 ± 1.38 for other Hyalomma spp, 3.86 ± 1.27 for Rhipicephalus annulatus, 3.56 ± 1.21 for Rh. appendiculatus, and 3.65 ± 1.30 for Rh. Pulchellus, but the difference was not significant (p = 0.443). Conclusion: This study illustrates the utility of 16S rRNA metagenomics in revealing the complexity of bacteria communities that reside and/or transit through the tick having been picked from the environment, livestock and/or wild animals, some with potential to cause zoonoses.

Virome diversity of ticks feeding on domestic mammals in China

Ticks are considered the second most common pathogen vectors transmitting a broad range of vital human and veterinary viruses.From 2017 to 2018,640 ticks were collected in eight different provinces in central and western China.Six species were detected,including H.longicornis,De.everestianus,Rh.microplus,Rh.turanicus,Rh.sanguineous,and Hy.asiaticum.Sixty-four viral metagenomic libraries were constructed on the MiSeq Illumina platform,resulting in 13.44 G(5.88×10^(7))of 250-bp-end reads,in which 2,437,941 are viral reads.We found 27 nearly complete genome sequences,including 16 genome sequences encoding entire protein-coding regions(lack of 30 or 50 end non-coding regions)and complete viral genomes,distributed in the arboviral family(Chuviridae,Rhabdoviridae,Nairoviridae,Phenuiviridae,Flaviviridae,Iflaviridae)as well as Parvoviridae and Polyomaviridae that cause disease in mammals and even humans.In addition,13 virus sequences found in Chuviridae,Nairoviridae,Flaviviridae,Iflaviridae,Hepeviridae,Parvoviridae,and Polyomaviridae were identified as belonging to a new virus species in the identified viral genera.Besides,an epidemiological survey shows a high prevalence(9.38%and 15.63%)of two viruses(Ovine Copiparvovirus and Bovine parvovirus 2)in the tick cohort.

A case of human infection with a novel Babesia species in China

Background:Babesiosis is an uncommon but emerging tick-borne disease caused by the genus Babesia.In this case study,we report a case of human infection with a novel Babesia sp.in China.Findings:The patient in question had been suffering from repetitive occurrences of mild fever of unknown origin and fatigue for 10 years.Ring forms,tetrads,and one or two dots of chromatin or trophozoite-like organisms were observed in the patient’s thin blood smears and bone marrow smears.Using a confocal laser-scanning microscope,it was observed that the patient’s serum had reactivity with the surface proteins of the B.microti strain.Electron microscopy revealed oval red blood cells with 1~2μm of knob protrusions in the cellular membrane.The results of the Babesia-specific nested PCR assay for 18S rRNA confirmed the presence of Babesia infection.The construction of a phylogenetic relationship showed clustering with B.microti and B.duncani,which was identified as a novel Babesia species and named as Babesia sp.XXB/HangZhou.Azithromycin,doxycycline,and moxifloxacin hydrochloride were shown to relieve symptoms but were not as effective after continuous usage.After atovaquone(Mepron®)administration,the patient recovered from fever and tested negative for detection of Babesia-specific genes.Conclusion:Babesia sp.XXB/HangZhou is a novel Babesia species,which causes mild babesiosis in an immunocompetent patient.