Humans infected with relapsing fever spirochete Borrelia miyamotoi, Russia

Geographic range and minimum infection rate of Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti, and Borrelia miyamotoi in Ixodes scapularis (Acari: Ixodidae) ticks in Manitoba, Canada from 1995 to 2017

INTRODUCTION

The expanding geographical range of blacklegged ticks (BLTs), Ixodes scapularis, and its ability to transmit Borrelia burgdorferi, Anaplasma phagocytophilum, Babesia microti, and Borrelia miyamotoi poses an emerging public health risk. Our study determined the geographic distribution and the minimum infection rate (MIR) of B. burgdorferi-, A. phagocytophilum-, Ba. microti-, and B. miyamotoi-infected BLTs in Manitoba submitted to the Public Health Agency of Canada's passive tick surveillance programme from 1995 to 2017.

METHODS

Regression models were used to test the association of the MIR by year for each pathogen. Ticks were tested using PCR for B. burgdorferi since 1995, A. phagocytophilum since 2006, and Ba. microti and B. miyamotoi since 2013. The global positioning system coordinates of infected and uninfected ticks submitted during the surveillance period were plotted on a map of Manitoba using ArcGIS Pro version 3.1.2 to detect changes in the geographic distribution of ticks over time.

RESULTS

The overall MIR for B. burgdorferi was 139.7 (95% confidence interval [CI]: 129.0-150.5) per 1000 BLTs; however, it varied over time. After remaining stable from 1995 to 2005, the MIR increased by 12.1 per 1000 BLTs per year from 2005 to 2017 (95% CI: 7.0%-17.2%, p-value <0.01). The geographic distribution of B. burgdorferi-infected BLTs was centred around Winnipeg, Manitoba, and spread outward from this locality. The MIRs of A. phagocytophilum, Ba. microti, and B. miyamotoi were 44.8 per 1000 BLTs (95% CI: 38.1-51.6), 10.8 (95% CI: 6.6-15.0), and 5.2 (95% CI: 2.3-8.1) per 1000 BLTs, respectively, and showed no significant change over time.

CONCLUSION

Passive surveillance revealed the presence of A. phagocytophilum-, Ba. microti-, and B. miyamotoi-infected BLTs in southern Manitoba and revealed an increased risk of exposure to B. burgdorferi-infected BLTs due to the increasing geographic range and MIR.

Exposure, infection and disease with the tick-borne pathogen Borrelia miyamotoi in the Netherlands and Sweden, 2007-2019

Using a novel multi-antigen protein array and diagnostic algorithm the exposure, infection, and disease caused by the emerging tick-borne pathogen Borrelia miyamotoi was investigated in the Netherlands and Sweden throughout different populations at risk of tick-bites over the past decades. ABSTRACT: The impact of the emerging tick-borne pathogen Borrelia miyamotoi is not fully understood. We utilized a protein array to investigate B. miyamotoi seroreactivity in various human populations in the Netherlands and Sweden. The IgM/IgG seroprevalence in Dutch healthy (2·5%, 95%CI 1·5-4·1) and population controls (2·0%, 95%CI 0·9-4·4) was lower (p=0·01 and p=0·01) compared to the tick-bite cohort (6·1%, 95%CI 3·9-9·5). In accordance, the Swedish healthy controls (1·0%, 95%CI 0·1-6·9) revealed a lower (p=0·005 and p<0·001) IgM/IgG seroprevalence compared to the tick-bite (8·9%, 95%CI 5·7-13·7) and fever after tick-bite cohort (16·5%, 95%CI 10·6-24·8). Altogether, 15 of 2,175 individuals had serologic evidence of early B. miyamotoi infection. The risk of infection with B. miyamotoi was 0·7% (95%CI 0·3-1·4) in tick-bitten individuals, and of disease 7·3% (95%CI 2·6-12·8) in those with a febrile illness after tick-bite. Our findings provide insights into the risk of infection and disease with this pathogen in Europe.

Pathogens transmitted by Ixodes ricinus

Ixodes ricinus is the most important tick vector in central and western Europe and one of the most researched parasites. However, in the published literature on the tick and the pathogens it transmits, conjecture about specific transmission cycles and the clinical significance of certain microbes is not always clearly separated from confirmed facts. This article aims to present up-to-date, evidence-based information about the well-researched human pathogens tick-borne encephalitis virus, louping-ill virus, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and several Babesia species, with a focus on their development in the tick, transmission dynamics and the competent reservoir hosts that support their circulation in the environment. Borrelia miyamotoi, Neoehrlichia mikurensis, Rickettsia helvetica and Rickettsia monacensis, which are much less common causes of disease but may affect immunocompromised patients, are also briefly discussed. Finally, the possible role of I. ricinus in the transmission of Coxiella burnetii, Francisella tularensis, Bartonella spp. and Spiroplasma ixodetis is reviewed.

Global risk dynamics of Borrelia miyamotoi in the context of climate change

The impact of Borrelia miyamotoi on human health, facilitated by the expanding geographical distribution and increasing population of Ixodes ticks, remains obscure in the context of global climate change. We employed multiple models to evaluate the effect of global climate change on the risk of B. miyamotoi worldwide across various scenarios. The habitat suitability index of four primary vector tick species for B. miyamotoi, including Ixodes persulcatus, Ixodes ricinus, Ixodes pacificus and Ixodes scapularis, was projected using a boosted regression tree model, considering multiple shared socio-economic pathway scenarios over various time periods. The modelling analysis reveals that, apart from I. scapularis, future global warming will result in a northward shift in the other three vector tick species and a gradual reduction in suitable habitats. Random forest models indicate consistent changes in B. miyamotoi and its primary tick species, with potential risk areas shrinking and shifting northward, particularly in the eastern USA, northeastern and northern Europe and northeast Asia. These findings highlight the urgent need for enhanced active surveillance of B. miyamotoi infection in primary vector tick species across projected potential risk areas. The effect of climate change on B. miyamotoi distribution might have significant implications for public health decision-making regarding tick-borne pathogens.

Molecular detection of some zoonotic tick-borne pathogens in ticks collected from camels (Camelus dromedarius) as hosts and wild rodents as potential reservoirs

Ticks and tick-borne pathogens pose a great threat to human and animal health. The present study aimed to determine the prevalence of ticks that infest camels and investigate the presence of tick-borne pathogens in the blood of camels, associated ticks, and surrounding rodents as reservoirs. From 100 inspected camels, from different localities in the Giza governorate, 1000 ixodid ticks were collected; these ticks belonged to three genera: Hyalomma, Amblyomma, and Rhipicephalus. The genus Hyalomma was represented by four species, Hyalomma dromedarii was the most prevalent species (55.4%), followed by Hyalomma excavatum (22%), Hyalomma impeltatum (11.6%) and Hyalomma rufipes (2.8%). The genus Amblyomma was represented by two species, Amblyomma gemma (2.8%) and Amblyomma marmoreum (2.7%), while the genus Rhipicephalus was represented by only one species, Rhipicephalus pulchellus (2.7%). Ticks, camel blood, and rodents (total number 100 brown rats) are screened for tick-borne pathogens (Borrelia burgdorferi, Borrelia miyamotoi, Babesia sp., and Coxiella burnetii) using PCR. Camel blood was found to be infected with Borrelia burgdorferi (66.6%), Borrelia miyamotoi (55%), and Babesia sp. (11.6%). Coxiella burnetii DNA was detected in all the collected ticks but was not detected in the blood of camels or rodents. Borrelia miyamotoi was detected in 12.5% of H. impeltatum, 55% of Camels, and 6% of the rodents, which may indicate a proposed risk of dispersal of B. miyamotoi, the agent of tick-borne relapsing fever.

Survey of tick-borne relapsing fever borreliae in southern and southeastern Kazakhstan

Tick-borne relapsing fever group borreliae (TBRFGB) are spirochetes that cause disease in humans and animals. Little is known about the prevalence of TBRFGB infections in ticks and humans in Kazakhstan. A total of 846 ticks belonging to ten species of the family Ixodidae and three species of the family Argasidae were collected from the vegetation, poultry shelters, domestic ruminants, bitten humans, pigeons, dogs and house walls in four oblasts of the southern and southeastern regions of Kazakhstan. The ticks were subjected to DNA extraction and identification of TBRFGB by conventional PCR using primers targeting flagella subunit B (flaB), glycerophosphodiester phosphodiesterase (glpQ) and P66 porin (P66) genes. The overall infection rate of TBRFGB in the ticks was 6.2 % (46/846). TBRFGB DNA was identified in Ixodes persulcatus (5.5 %; 26/477), Ornithodoros tartakovskyi (6 %; 2/36) and Argas persicus (13.4 %; 18/134) ticks. Partial sequencing of flaB, glpQ and P66 genes identified Borrelia miyamotoi in I. persulcatus and Borrelia anserina in A. persicus. To detect the presence of B. miyamotoi infection in people in the study region, we performed serological analysis of samples collected from 42 patients admitted to hospital with fever of unknown etiology or with a history of a tick bite. The analysis revealed IgM and IgG antibodies against one or several B. miyamotoi antigens in 10 % and 5 % of patients, respectively. The data obtained provide strong evidence of the presence of B. miyamotoi and B. anserina in the southern and southeastern regions of Kazakhstan, underscoring the need for increased awareness of potential infections caused by these borreliae in these regions.

Combining short- and long-read sequencing unveils geographically structured diversity in Borrelia miyamotoi

Borrelia miyamotoi is an emerging Ixodes tick-borne human pathogen in the Northern hemisphere. The aim of the current study was to compare whole genome sequences of B. miyamotoi isolates from different continents. Using a combination of Illumina and PacBio platforms and a novel genome assembly and plasmid typing pipeline, we reveal that the 21 sequenced B. miyamotoi isolates and publically available B. miyamotoi genomes from North America, Asia, and Europe form genetically distinct populations and cluster according to their geographical origin, where distinct Ixodes species are endemic. We identified 20 linear and 17 circular plasmid types and the presence of specific plasmids for isolates originating from different continents. Linear plasmids lp12, lp23, lp41, and lp72 were core plasmids found in all isolates, with lp41 consistently containing the vmp expression site. Our data provide insights into the genetic basis of vector competence, virulence, and pathogenesis of B. miyamotoi.

Bacterial pathogens in Ixodes ricinus collected from lizards Lacerta agilis and Zootoca vivipara in urban areas of Wrocław, SW Poland- preliminary study

The aim of this study was to determine the level of infection of Ixodes ricinus ticks with pathogens (Borrelia spp., Rickettsia spp., and Anaplasma spp.) collected from Lacerta agilis and Zootoca vivipara lizards in the urban areas of Wrocław (SW Poland). The study was carried out in July-August 2020. Lizards were caught by a noose attached to a pole or by bare hands, identified by species, and examined for the presence of ticks. Each lizard was then released at the site of capture. Ticks were removed with tweezers, identified by species using keys, and molecular tests were performed for the presence of pathogens. From 28 lizards (17 specimens of Z. vivipara and 11 specimens of L. agilis) a total of 445 ticks, including 321 larvae and 124 nymphs, identified as I. ricinus were collected. A larger number of ticks were obtained from L. agilis compared to Z. vivipara. Molecular tests for the presence of pathogens were performed on 445 specimens of I. ricinus. The nested PCR method for the fla gene allowed the detection of Borrelia spp. in 9.4% of ticks, and it was higher in ticks from L. agilis (12.0%) than from Z. vivipara (1.0%). The RFLP method showed the presence of three species, including two belonging to the B. burgdorferi s.l. complex (B. lusitaniae and B. afzelii), and B. miyamotoi. The overall level of infection of Rickettsia spp. was 19.3%, including 27.2% in ticks collected from Z. vivipara and 17.0% from L. agilis. Sequencing of randomly selected samples confirmed the presence of R. helvetica. DNA of Anaplasma spp. was detected only in one pool of larvae collected from L. agilis, and sample sequencing confirmed the presence of (A) phagocytophilum. The research results indicate the important role of lizards as hosts of ticks and their role in maintaining pathogens in the environment including urban agglomeration as evidenced by the first recorded presence of (B) miyamotoi and (A) phagocytophilum in I. ricinus ticks collected from L. agilis. However, confirmation of the role of sand lizards in maintaining (B) miyamotoi and A. phagocytophilum requires more studies and sampling of lizard tissue.

Acute Meningoencephalitis Associated with Borrelia miyamotoi, Minnesota, USA

Borrelia miyamotoi is an emerging tickborne pathogen that has been associated with central nervous system infections in immunocompromised patients, albeit infrequently. We describe a case-patient in Minnesota, USA, who had meningeal symptoms of 1 month duration. B. miyamotoi infection was diagnosed by Gram staining on cerebrospinal fluid and confirmed by sequencing.

Prevalence of Lyme Disease and Relapsing Fever Borrelia spp. in Vectors, Animals, and Humans within a One Health Approach in Mediterranean Countries

The genus Borrelia has been divided into Borreliella spp., which can cause Lyme Disease (LD), and Borrelia spp., which can cause Relapsing Fever (RF). The distribution of genus Borrelia has broadened due to factors such as climate change, alterations in land use, and enhanced human and animal mobility. Consequently, there is an increasing necessity for a One Health strategy to identify the key components in the Borrelia transmission cycle by monitoring the human-animal-environment interactions. The aim of this study is to summarize all accessible data to increase our understanding and provide a comprehensive overview of Borrelia distribution in the Mediterranean region. Databases including PubMed, Google Scholar, and Google were searched to determine the presence of Borreliella and Borrelia spp. in vectors, animals, and humans in countries around the Mediterranean Sea. A total of 3026 were identified and screened and after exclusion of papers that did not fulfill the including criteria, 429 were used. After examination of the available literature, it was revealed that various species associated with LD and RF are prevalent in vectors, animals, and humans in Mediterranean countries and should be monitored in order to effectively manage and prevent potential infections.

Systematic investigation of the Borrelia miyamotoi spirochetes in ticks, wildlife and domestic animal hosts in Yunnan province, Southwest China

Background

Borrelia miyamotoi is a spirochete species transmitted via hard ticks. Following its discovery in Japan, this pathogen has been detected around the world, and is increasingly confirmed as a human pathogen causing febrile disease, namely relapsing fever. Its presence has been confirmed in the Northeast China. However, there is little information regarding the presence of B. miyamotoi and other hard-tick-borne relapsing fever spirochetes in southern China including Yunnan province, where tick and animal species are abundant and many people both inhabit and visit for recreation.

Methods

For the present study, we collected samples of ticks, wildlife, and domestic animal hosts from different counties in Yunnan province. Nucleic acids from samples were extracted, and the presence of B. miyamotoi and other relapsing fever spirochetes was confirmed using polymerase chain reaction (PCR) for the 16S rRNA specific target gene fragment. The positive samples were then amplified for partial genome of the flaB and glpQ genes. Statistical differences in its distribution were analyzed by SPSS 20 software. Sequence of partial 16S rRNA, flaB and glpQ genome were analyzed and phylogenetic trees were constructed.

Results

A total of 8260 samples including 2304 ticks, 4120 small mammals and 1836 blood of domestic animal hosts were collected for screening for infection of B. miyamotoi and other relapsing fever spirochetes. Cattle and sheep act as the main hosts and Rhipicephalus microplus, Haemaphysalis nepalensis, H. kolonini and Ixodes ovatus were identified as the important vector host with high prevalence or wide distribution. Only one Mus caroli (mouse) and one Sorex alpinus (shrew) were confirmed positive for relapsing fever spirochetes. Evidence of vertical transmission in ticks was also confirmed. Two known strains of B. miyamotoi and one novel relapsing fever spirochetes, B. theileri-like agent, were confirmed and described with their host adaptation, mutation, and potential risk of spreading and spillover for human beings.

Conclusions

Our results provide new evidence of relapsing fever spirochetes in vector and animal hosts in Yunnan province based on large sample sizes, and offer guidance on further investigation, surveillance and monitoring of this pathogen.

Borrelia miyamotoi BipA-like protein, BipM, is a candidate serodiagnostic antigen distinguishing between Lyme disease and relapsing fever Borrelia infections

A Borrelia miyamotoi gene with partial homology to bipA of relapsing fever spirochetes Borrelia hermsii and Borrelia turicatae was identified by a GenBank basic alignment search analysis. We hypothesized that this gene product may be an immunogenic antigen as described for other relapsing fever Borrelia (RFB) and could serve as a serological marker for B. miyamotoi infections. The B. miyamotoi gene was a truncated version about half the size of the B. hermsii and B. turicatae bipA with a coding sequence of 894 base pairs. The gene product had a calculated molecular size of 32.7 kDa (including the signal peptide). Amino acid alignments with B. hermsii and B. turicatae BipA proteins and with other B. miyamotoi isolates showed conservation at the carboxyl end. We cloned the B. miyamotoi bipA-like gene (herein named bipM) and generated recombinant protein for serological characterization and for antiserum production. Protease protection analysis demonstrated that BipM was surface exposed. Serologic analyses using anti-B. miyamotoi serum samples from tick bite-infected and needle inoculated mice showed 94 % positivity against BipM. The 4 BipM negative serum samples were blotted against another B. miyamotoi antigen, BmaA, and two of them were seropositive resulting in 97 % positivity with both antigens. Serum samples from B. burgdorferi sensu stricto (s.s.)-infected mice were non-reactive against rBipM by immunoblot. Serum samples from Lyme disease patients were also serologically negative against BipM except for 1 sample which may have indicated a possible co-infection. A recently published study demonstrated that B. miyamotoi BipM was non-reactive against serum samples from B. hermsii, Borrelia parkeri, and B. turicatae infected animals. These results show that BipM has potential for a B. miyamotoi-infection specific and sensitive serodiagnostic to differentiate between Lyme disease and various RFB infections.

Emerging Tick-borne Infections in the Upper Midwest and Northeast United States Among Patients With Suspected Anaplasmosis

Background

Emerging tick-transmitted illnesses are increasingly recognized in the United States (US). To identify multiple potential tick-borne pathogens in patients from the Upper Midwest and Northeast US with suspected anaplasmosis, we used state-of-the-art methods (polymerase chain reaction [PCR] and paired serology) to test samples from patients in whom anaplasmosis had been excluded.

Methods

Five hundred sixty-eight patients without anaplasmosis had optimal samples available for confirmation of alternative tick-borne pathogens, including PCR and/or paired serology (acute-convalescent interval ≤42 days).

Results

Among 266 paired serology evaluations, for which the median acute-convalescent sampling interval was 28 (interquartile range, 21-33) days, we identified 35 acute/recent infections (24 [9%] Borrelia burgdorferi; 6 [2%] Ehrlichia chaffeensis/Ehrlichia muris subsp eauclairensis [EC/EME]; 3 [1%] spotted fever group rickettsioses [SFGR], and 2 [<1%] Babesia microti) in 33 (12%) patients. Two had concurrent or closely sequential infections (1 B burgdorferi and EC/EME, and 1 B burgdorferi and SFGR). Using multiplex PCR and reverse-transcription PCR, we identified 7 acute infections (5/334 [1%] Borrelia miyamotoi and 2/334 [1%] B microti) in 5 (1%) patients, including 2 with B microti-B miyamotoi coinfection, but no Borrelia mayonii, SFGR, Candidatus Anaplasma capra, Heartland virus, or Powassan virus infections. Thus, among 568 patients with ruled-out anaplasmosis, 38 (6.7%) had ≥1 agent of tick-borne illness identified, with 33 patients (35 infections) diagnosed by paired serology and 5 additional patients (7 infections) by PCR.

Conclusions

By identifying other tick-borne agents in patients in whom anaplasmosis had been excluded, we demonstrate that emerging tick-borne infections will be identified if specifically sought.

Human Tick-Borne Diseases and Advances in Anti-Tick Vaccine Approaches: A Comprehensive Review

This comprehensive review explores the field of anti-tick vaccines, addressing their significance in combating tick-borne diseases of public health concern. The main objectives are to provide a brief epidemiology of diseases affecting humans and a thorough understanding of tick biology, traditional tick control methods, the development and mechanisms of anti-tick vaccines, their efficacy in field applications, associated challenges, and future prospects. Tick-borne diseases (TBDs) pose a significant and escalating threat to global health and the livestock industries due to the widespread distribution of ticks and the multitude of pathogens they transmit. Traditional tick control methods, such as acaricides and repellents, have limitations, including environmental concerns and the emergence of tick resistance. Anti-tick vaccines offer a promising alternative by targeting specific tick proteins crucial for feeding and pathogen transmission. Developing vaccines with antigens based on these essential proteins is likely to disrupt these processes. Indeed, anti-tick vaccines have shown efficacy in laboratory and field trials successfully implemented in livestock, reducing the prevalence of TBDs. However, some challenges still remain, including vaccine efficacy on different hosts, polymorphisms in ticks of the same species, and the economic considerations of adopting large-scale vaccine strategies. Emerging technologies and approaches hold promise for improving anti-tick vaccine development and expanding their impact on public health and agriculture.

Characteristics of Hard Tick Relapsing Fever Caused by Borrelia miyamotoi, United States, 2013-2019

Borrelia miyamotoi, transmitted by Ixodes spp. ticks, was recognized as an agent of hard tick relapsing fever in the United States in 2013. Nine state health departments in the Northeast and Midwest have conducted public health surveillance for this emerging condition by using a shared, working surveillance case definition. During 2013-2019, a total of 300 cases were identified through surveillance; 166 (55%) were classified as confirmed and 134 (45%) as possible. Median age of case-patients was 52 years (range 1-86 years); 52% were male. Most cases (70%) occurred during June-September, with a peak in August. Fever and headache were common symptoms; 28% of case-patients reported recurring fevers, 55% had arthralgia, and 16% had a rash. Thirteen percent of patients were hospitalized, and no deaths were reported. Ongoing surveillance will improve understanding of the incidence and clinical severity of this emerging disease.

Case report: First case of Borrelia miyamotoi meningitis in an immunocompromised patient in Norway

Background

Tick-borne disease caused by B. miyamotoi (BMD) usually manifest as a febrile illness in humans. Complications include relapsing fever and in rare occasions involvement of the central nervous system. Only a few cases of meningoencephalitis have been described, mostly in immunosuppressed patients.

Case presentation

A 70-year-old female receiving immunosuppressive rituximab therapy presented with frontal headache, dizziness, nausea, vomiting and chills. Clinical laboratory blood analyses were normal. Cerebrospinal fluid (CSF) was translucent and analysis showed increased leucocyte count (187 106/L) and elevated level of protein (1056 mg/L). Empiric antibiotic treatment was initiated. The patient showed an early symptomatic relief and 24 h after admission she was discharged from the hospital and antibiotic treatment was discontinued. Two weeks after hospitalisation the B. miyamotoi specific PCR turned out positive in both CSF and serum. At the time, the patient was recovered with mild residual headache. She was treated with high dose doxycycline and her subtle symptoms disappeared.

Conclusions

To our knowledge, we present the first patient with BMD-associated meningitis in Norway, one of eight cases reported worldwide. The patient had mild symptoms and received an early diagnosis. A more severe progression or relapse of disease may have been prevented by antibiotic treatment. BMD should be considered as causes of aseptic meningitis, especially in immunosuppressed patients living in endemic areas.

Spatiotemporal distribution of Borrelia miyamotoi (Spirochaetales: Spirochaetaceae) and coinfection with other tick-borne pathogens in host-seeking Ixodes scapularis (Acari: Ixodidae) from New York State, USA

Blacklegged ticks (Ixodes scapularis Say, Acari: Ixodidae) were collected from 432 locations across New York State (NYS) during the summer and autumn of 2015-2020 to determine the prevalence and geographic distribution of Borrelia miyamotoi (Spirochaetales: Spirochaetaceae) and coinfections with other tick-borne pathogens. A total of 48,386 I. scapularis were individually analyzed using a multiplex real-time polymerase chain reaction assay to simultaneously detect the presence of Bo. miyamotoi, Borrelia burgdorferi (Spirochaetales: Spirochaetaceae), Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae), and Babesia microti (Piroplasmida: Babesiidae). Overall prevalence of Bo. miyamotoi in host-seeking nymphs and adults varied geographically and temporally at the regional level. The rate of polymicrobial infection in Bo. miyamotoi-infected ticks varied by developmental stage, with certain co-infections occurring more frequently than expected by chance. Entomological risk of exposure to Bo. miyamotoi-infected nymphal and adult ticks (entomological risk index [ERI]) across NYS regions in relation to human cases of Bo. miyamotoi disease identified during the study period demonstrated spatial and temporal variation. The relationship between select environmental factors and Bo. miyamotoi ERI was explored using generalized linear mixed effects models, resulting in different factors significantly impacting ERI for nymphs and adult ticks. These results can inform estimates of Bo. miyamotoi disease risk and further our understanding of Bo. miyamotoi ecological dynamics in regions where this pathogen is known to occur.

Exposure of dogs and cats to Borrelia miyamotoi infected Ixodes ricinus ticks in urban areas of the city of Poznań, west-central Poland

Borrelia miyamotoi is an emerging human pathogen that causes a relapsing fever-like disease named B. miyamotoi disease. The bacterium belongs to the relapsing fever borreliae, and similar to spirochetes of the Borrelia burgdorferi sensu lato group, it is transmitted only by hard ticks of the Ixodes ricinus complex. To date, B. miyamotoi has not been demonstrated to cause illness in dogs or cats, and is poorly documented in veterinary medicine. The aim of this study was to determine the B. miyamotoi presence in (i) host-seeking ticks and (ii) engorged Ixodes sp. ticks collected from dogs and cats during their inspection in veterinary clinics of the city of Poznań, west-central Poland. Host-seeking ticks were sampled in dog walking areas localized in urban forested recreational sites of the city. In this study, 1,059 host-seeking and 837 engorged I. ricinus ticks collected from 680 tick-infested animals (567 dogs and 113 cats) were screened. Additionally, 31 I. hexagonus ticks (one larva, 13 nymphs, and 17 females) were collected from three cats; one larva and one nymph were collected from two dogs; and one dog was infested with a single Dermacentor reticulatus female. Borrelia DNA was identified by the amplification and sequencing of the V4 hypervariable region of the 16S rRNA gene and flaB gene fragments. DNA of B. miyamotoi was detected in 22 (2.1%) of the host-seeking ticks (in all developmental tick stages and in all study areas). In addition, the engorged I. ricinus ticks exhibited a similar B. miyamotoi presence (1.8%). Fifteen I. ricinus ticks collected from animals tested positive for the presence of B. miyamotoi DNA, and the DNA of B. miyamotoi was observed in three (9.1%; one female and two nymphs) I. hexagonus ticks. The single D. reticulatus female collected from a dog tested PCR-negative for the bacterium. The results of this study demonstrated the establishment and broad presence of the bacterium in tick populations from different urban ecosystems of the city of Poznań. The lack of difference in the mean infection presence of animal-derived and host-seeking I. ricinus ticks suggests that the systematic surveillance of pets may be useful for the evaluation of human exposure to B. miyamotoi infected ticks in urban areas. Additional studies are required to further elucidate the role of domestic and wild carnivores in the epidemiology of B. miyamotoi, which remains unknown.

Borrelia miyamotoi in wild rodents from four different regions of Turkey

Borrelia miyamotoi is a tick-borne zoonotic agent that causes hard tick-borne relapsing fever, an emerging disease in humans. Some small mammalian and bird species are reported to be reservoirs of B. miyamotoi. This study aims to examine Borrelia species present in rodents captured from rural areas of Turkey. Blood samples of rodents were initially screened with Borrelia 16S rRNA qPCR. The Borrelia flaB gene was subsequently amplified by conventional PCR, after which all positive samples were sequenced. Borrelia miyamotoi was observed in nine out of 536 blood samples (1.7%) collected from wild rodents. Phylogenetic analysis showed that all positive samples belonged to the European genotype clade of B. miyamotoi. PCR positivity was 5.3%, 3.7%, and 1.8% in Apodemus uralensis, Apodemus flavicollis, and Myodes glareolus, respectively. Borrelia burgdorferi sensu lato that causes Lyme borreliosis in humans could not be detected in the rodents. In this study, presence of B. miyamotoi DNA is reported for the first time in rodents in Turkey.

Tick-borne diseases under the radar in the North Sea Region

The impact of tick-borne diseases caused by pathogens such as Anaplasma phagocytophilum, Neoehrlichia mikurensis, Borrelia miyamotoi, Rickettsia helvetica and Babesia species on public health is largely unknown. Data on the prevalence of these pathogens in Ixodes ricinus ticks from seven countries within the North Sea Region in Europe as well as the types and availability of diagnostic tests and the main clinical features of their corresponding diseases is reported and discussed. Raised awareness is needed to discover cases of these under-recognized types of tick-borne disease, which should provide valuable insights into these diseases and their clinical significance.

Combining citizen science and molecular diagnostic methods to investigate the prevalence of Borrelia burgdorferi s.l. and Borrelia miyamotoi in tick pools across Great Britain

Lyme disease is the most common tick-borne disease and is caused by a group of bacteria known as Borrelia burgdorferi sensu lato (s.l.) complex. Sharing the same genus as B. burgdorferi, Borrelia miyamotoi is a distinct genotype that causes relapsing fever disease. This emerging tick-borne disease is increasingly becoming a concern in public health. To investigate the prevalence of B. burgdorferi s.l. and B. miyamotoi in ticks first, we developed a PCR (Bmer-qPCR) that targets the phage terminase large subunit (terL) gene carried by B. miyamotoi. A similar approach had been used successfully in developing Ter-qPCR for detecting B. burgdorferi s.l. The terL protein functions as an enzyme in packaging phage DNA. Analytical validation of the Bmer-qPCR confirmed its specificity, efficiency and sensitivity. Second, we designed a citizen science-based approach to detect 838 ticks collected from numerous sites across Great Britain. Finally, we applied Bmer-qPCR and Ter-qPCR to 153 tick pools and revealed that the prevalence of B. burgdorferi s.l. and B. miyamotoi was dependent on their geographical locations, i.e. Scotland showed a higher rate of B. burgdorferi s.l. and lower rate of B. miyamotoi carriage as compared to those of the England data. A pattern of diminishing rate of B. miyamotoi carriage from southern England to northern Scotland was visible. Together, the citizen science-based approach provided an estimation of the carriage rate of B. burgdorferi s.l. and B. miyamotoi in tick pools and a potential spreading pattern of B. miyamotoi from the south to the north of Great Britain. Our findings underscore the power of combining citizen science with the molecular diagnostic method to reveal hidden pattern of pathogen-host-environment interplay. Our approach can provide a powerful tool to elucidate the ecology of tick-borne diseases and may offer guidance for pathogen control initiatives. In an era of limited resources, monitoring pathogens requires both field and laboratory support. Citizen science approaches provide a method to empower the public for sample collection. Coupling citizen science approaches with laboratory diagnostic tests can make real-time monitoring of pathogen distribution and prevalence possible.

Genetic Diversity of Borreliaceae Species Detected in Natural Populations of Ixodes ricinus Ticks in Northern Poland

In Europe, Ixodes ricinus tick is the vector of Lyme disease spirochetes and their relatives (Borreliella genus) and Borrelia miyamotoi. However, a newly described tick I. inopinatus with similar biological features and separated from I. ricinus may act as a vector for different Borrelia species. To date, eleven Borreliella species were detected in the natural populations of I. ricinus. Recently, two North American species have been detected in ticks parasitizing bats and red foxes in Europe, i.e., B. lanei and B. californiensis pointing to the necessity for searching for them in natural tick populations. In this study, using the coxI molecular marker only I. ricinus was identified in field-collected ticks with the exception of individual specimens of Haemaphysalis concinna. Using the flaB gene and mag-trnI intergenic spacer as molecular markers 14 Borreliaceae species have been detected with various frequencies in different parts of northern Poland. Among infected ticks, the most frequent were Borreliella (Bl.) afzelii (29.4%) and Bl. garinii (20.0%), followed by Bl. spielmanii, Bl. valaisiana, Bl. lanei, Bl. californiensis, B. miyamotoi, Bl. burgdorferi, Bl. carolinensis, Bl. americana, B. turcica, Bl. lusitaniae, Bl. bissettiae and Bl. finlandensis. Three of the above-mentioned species, i.e., Bl. lanei, Bl. californiensis and B. turcica were detected in this study for the first time in the natural ixodid tick population in Europe. The existence of the newly detected spirochetes increases their total diversity in Europe and points to the necessity of careful identification and establishment of the actual distribution of all Borreliaceae species transmitted by I. ricinus.

Human Borrelia miyamotoi Infection in North America

Borrelia miyamotoi is an emerging pathogen that causes a febrile illness and is transmitted by the same hard-bodied (ixodid) ticks that transmit several other pathogens, including Borrelia species that cause Lyme disease. B. miyamotoi was discovered in 1994 in Ixodes persulcatus ticks in Japan. It was first reported in humans in 2011 in Russia. It has subsequently been reported in North America, Europe, and Asia. B. miyamotoi infection is widespread in Ixodes ticks in the northeastern, northern Midwestern, and far western United States and in Canada. In endemic areas, human B. miyamotoi seroprevalence averages from 1 to 3% of the population, compared with 15 to 20% for B. burgdorferi. The most common clinical manifestations of B. miyamotoi infection are fever, fatigue, headache, chills, myalgia, arthralgia, and nausea. Complications include relapsing fever and rarely, meningoencephalitis. Because clinical manifestations are nonspecific, diagnosis requires laboratory confirmation by PCR or blood smear examination. Antibiotics are effective in clearing infection and are the same as those used for Lyme disease, including doxycycline, tetracycline, erythromycin, penicillin, and ceftriaxone. Preventive measures include avoiding areas where B. miyamotoi-infected ticks are found, landscape management, and personal protective strategies such as protective clothing, use of acaricides, and tick checks with rapid removal of embedded ticks.

Detection, identification and genotyping of Borrelia spp. in ticks of Coastal-Karst and Littoral-Inner Carniola regions in Slovenia

The density and spread of tick vector species have increased throughout Europe in the last 30 years, leading to an increase of Lyme borreliosis cases, including in Slovenia. The aim of this study was to isolate Borrelia strains and determine the prevalence of B. burgdorferi sensu lato and B. miyamotoi in adults of Ixodes ricinus (Linnaeus) collected in 2019 in the two regions of the country (Coastal-Karst and Littoral-Inner Carniola) by cultivation and PCR. We isolated B. burgdorferi s.l. by culture method in 28/559 (5%) ticks from both regions. Culture-negative samples (531/559, i.e., 95%) were additionally tested by real-time PCR. In 155/531 (29.2%) PCR-positive samples, a fragment of flaB or glpQ was amplified and further sequenced to identify species of the Borrelia. Using both methods, cultivation and PCR, Borrelia spp. prevalence was 32.7% in the Coastal-Karst region and 33.0% in the Littoral-Inner Carniola region. Genotyping of the Borrelia spp. isolates revealed that 17/28 (60%) were B. garinii subtype Mlg2. Of all tick samples tested for B. miyamotoi 8/398 (2%) were PCR positive. Based on previous studies in these regions, we had expected more ticks to be infected with B. afzelii, but genotyping revealed that B. garinii was the most abundant.

Analysis of variable major protein antigenic variation in the relapsing fever spirochete, Borrelia miyamotoi, in response to polyclonal antibody selection pressure

Borrelia miyamotoi is a tick-transmitted spirochete that is genetically grouped with relapsing fever Borrelia and possesses multiple archived pseudogenes that encode variable major proteins (Vmps). Vmps are divided into two groups based on molecular size; variable large proteins (Vlps) and variable small proteins (Vsps). Relapsing fever Borrelia undergo Vmp gene conversion at a single expression locus to generate new serotypes by antigenic switching which is the basis for immune evasion that causes relapsing fever in patients. This study focused on B. miyamotoi vmp expression when spirochetes were subjected to antibody killing selection pressure. We incubated a low passage parent strain with mouse anti-B. miyamotoi polyclonal antiserum which killed the majority population, however, antibody-resistant reisolates were recovered. PCR analysis of the gene expression locus in the reisolates showed vsp1 was replaced by Vlp-encoded genes. Gel electrophoresis protein profiles and immunoblots of the reisolates revealed additional Vlps indicating that new serotype populations were selected by antibody pressure. Sequencing of amplicons from the expression locus of the reisolates confirmed the presence of a predominant majority serotype population with minority variants. These findings confirm previous work demonstrating gene conversion in B. miyamotoi and that multiple serotype populations expressing different vmps arise when subjected to antibody selection. The findings also provide evidence for spontaneous serotype variation emerging from culture growth in the absence of antibody pressure. Validation and determination of the type, number, and frequency of serotype variants that arise during animal infections await further investigations.

The Surveillance of Borrelia Species in Camelus dromedarius and Associated Ticks: The First Detection of Borrelia miyamotoi in Egypt

Tick-borne diseases (TBDs) are emerging and re-emerging infections that have a worldwide impact on human and animal health. Lyme borreliosis (LB) is a severe zoonotic disease caused by the spirochete Borrelia burgdorferi sensu lato (s.l.) transmitted to humans by the bite of infected Ixodes ticks. Borrelia miyamotoi is a spirochete that causes relapsing fever (RF) and is genetically related to Borrelia burgdorferi s.l. However, there have been no reports of B. miyamotoi in Egypt, and the data on LB in camels is scarce. Thus, the present study was conducted to screen and genetically identify Borrelia spp. and B. miyamotoi in Egyptian camels and associated ticks using polymerase chain reaction (PCR).

METHODS

A total of 133 blood samples and 1596 adult hard ticks were collected from Camelus dromedaries at Cairo and Giza slaughterhouses in Egypt. Tick species were identified by examining their morphology and sequencing the cytochrome C oxidase subunit 1 (cox1) gene. Borrelia spp. was detected using nested PCR on the IGS (16S-23S) gene, and positive samples were genotyped using 16S rRNA and glpQ spp. genes specific for Borrelia burgdorferi and Borrelia miyamotoi, respectively. The positive PCR products were sequenced and analyzed by phylogenetic tree.

RESULTS

Analysis of the cox1 gene sequence revealed that the adult ticks belonged to three genera; Hyalomma (H), Amblyomma (Am), and Rhipicephalus (R), as well as 12 species, including H. dromedarii, H. marginatum, H. excavatum, H. anatolicum, R. annulatus, R. pulchellus, Am. testudinarium, Am. hebraeum, Am. lipidium, Am. variegatum, Am. cohaerens and Am. gemma. Borrelia spp. was found in 8.3% (11/133) of the camel blood samples and 1.3% (21/1596) of the ticks, respectively. Sequencing of the IGS (16S-23S) gene found that B. afzelii, detected from H. dromedarii and H. marginatum, and B. crocidurae, which belongs to the RF group, was detected from one blood sample. B. burgdorferi and B. miyamotoi were discovered in the blood samples and tick species. Phylogenetic analysis of the glpQ gene showed that the B. miyamotoi in this study was of the Asian and European types.

CONCLUSIONS

These results suggest that the camels can be infected by Lyme borrelia and other Borrelia bacteria species. This study also provides the first insight into the presence of Borrelia miyamotoi and B. afzelii DNA in camels and associated ticks in Egypt.

Borrelia miyamotoi: A Comprehensive Review

Borrelia miyamotoi is an emerging tick-borne pathogen in the Northern Hemisphere and is the causative agent of Borrelia miyamotoi disease (BMD). Borrelia miyamotoi is vectored by the same hard-bodied ticks as Lyme disease Borrelia, yet phylogenetically groups with relapsing fever Borrelia, and thus, has been uniquely labeled a hard tick-borne relapsing fever Borrelia. Burgeoning research has uncovered new aspects of B. miyamotoi in human patients, nature, and the lab. Of particular interest are novel findings on disease pathology, prevalence, diagnostic methods, ecological maintenance, transmission, and genetic characteristics. Herein, we review recent literature on B. miyamotoi, discuss how findings adapt to current Borrelia doctrines, and briefly consider what remains unknown about B. miyamotoi.

Borrelia miyamotoi a neglected tick-borne relapsing fever spirochete in Thailand

Borrelia miyamotoi is a relapsing fever spirochete that shares the same vector as Lyme disease causing Borrelia. This epidemiological study of B. miyamotoi was conducted in rodent reservoirs, tick vectors and human populations simultaneously. A total of 640 rodents and 43 ticks were collected from Phop Phra district, Tak province, Thailand. The prevalence rate for all Borrelia species was 2.3% and for B. miyamotoi was 1.1% in the rodent population, while the prevalence rate was quite high in ticks collected from rodents with an infection rate of 14.5% (95% CI: 6.3-27.6%). Borrelia miyamotoi was detected in Ixodes granulatus collected from Mus caroli and Berylmys bowersi, and was also detected in several rodent species (Bandicota indica, Mus spp., and Leopoldamys sabanus) that live in a cultivated land, increasing the risk of human exposure. Phylogenetic analysis revealed that the B. miyamotoi isolates detected in rodents and I. granulatus ticks in this study were similar to isolates detected in European countries. Further investigation was conducted to determine the serological reactivity to B. miyamotoi in human samples received from Phop Phra hospital, Tak province and in rodents captured from Phop Phra district using an in-house, direct enzyme-linked immunosorbent assay (ELISA) assay with B. miyamotoi recombinant glycerophosphodiester-phosphodiesterase (rGlpQ) protein as coated antigen. The results showed that 17.9% (15/84) of human patients and 9.0% (41/456) of captured rodents had serological reactivity to B. miyamotoi rGlpQ protein in the study area. While a low level of IgG antibody titers (100-200) was observed in the majority of seroreactive samples, higher titers (400-1,600) were also detected in both humans and rodents. This study provides the first evidence of B. miyamotoi exposure in human and rodent populations in Thailand and the possible roles of local rodent species and Ixodes granulatus tick in its enzootic transmission cycle in nature.

Evaluation of Immunocompetent Mouse Models for Borrelia miyamotoi Infection

Borrelia miyamotoi is a relapsing fever spirochete that is harbored by Ixodes spp. ticks and is virtually uncharacterized, compared to other relapsing fever Borrelia vectored by Ornithodoros spp. ticks. There is not an immunocompetent mouse model for studying B. miyamotoi infection in vivo or for transmission in the vector-host cycle. Our goal was to evaluate B. miyamotoi infections in multiple mouse breeds/strains as a prelude to the ascertainment of the best experimental infection model. Two B. miyamotoi strains, namely, LB-2001 and CT13-2396, as well as three mouse models, namely, CD-1, C3H/HeJ, and BALB/c, were evaluated. We were unable to observe B. miyamotoi LB-2001 spirochetes in the blood via darkfield microscopy or to detect DNA via real-time PCR post needle inoculation in the CD-1 and C3H/HeJ mice. However, LB-2001 DNA was detected via real-time PCR in the blood of the BALB/c mice after needle inoculation, although spirochetes were not observed via microscopy. CD-1, C3H/HeJ, and BALB/c mice generated an antibody response to B. miyamotoi LB-2001 following needle inoculation, but established infections were not detected, and the I. scapularis larvae failed to acquire spirochetes from the exposed CD-1 mice. In contrast, B. miyamotoi CT13-2396 was visualized in the blood of the CD-1 and C3H/HeJ mice via darkfield microscopy and detected by real-time PCR post needle inoculation. Both mouse strains seroconverted. However, no established infection was detected in the mouse organs, and the I. scapularis larvae failed to acquire Borrelia after feeding on CT13-2396 exposed CD-1 or C3H/HeJ mice. These findings underscore the challenges in establishing an experimental B. miyamotoi infection model in immunocompetent laboratory mice. IMPORTANCE Borrelia miyamotoi is a causative agent of hard tick relapsing fever, was first identified in the early 1990s, and was characterized as a human pathogen in 2011. Unlike other relapsing fever Borrelia species, B. miyamotoi spread by means of Ixodes ticks. The relatively recent recognition of this human pathogen means that B. miyamotoi is virtually uncharacterized, compared to other Borrelia species. Currently there is no standard mouse-tick model with which to study the interactions of the pathogen within its vector and hosts. We evaluated two B. miyamotoi isolates and three immunocompetent mouse models to identify an appropriate model with which to study tick-host-pathogen interactions. With the increased prevalence of human exposure to Ixodes ticks, having an appropriate model with which to study B. miyamotoi will be critical for the future development of diagnostics and intervention strategies.

Molecular Surveillance for Vector-Borne Bacteria in Rodents and Tree Shrews of Peninsular Malaysia Oil Palm Plantations

Many human clinical cases attributed to vector-borne pathogens are underreported in Malaysia, especially in rural localities where healthcare infrastructures are lacking. Here, 217 small mammals, consisting of rodents and tree shrews, were trapped in oil palm plantations in the Peninsular Malaysia states of Johor and Perak. Species identification was performed using morphological and DNA barcoding analyses, and 203 small mammals were included in the detection of selected vector-borne bacteria. The DNA extracted from the spleens was examined for Orientia tsutsugamushi, Borrelia spp., Bartonella spp. and Rickettsia spp. using established PCR assays. The small mammals collected in this study included Rattus tanezumi R3 mitotype (n = 113), Rattus argentiventer (n = 24), Rattus tiomanicus (n = 22), Rattus exulans (n = 17), Rattus tanezumi sensu stricto (n = 1) and Tupaia glis (n = 40). Orientia tsutsugamushi, Borrelia spp. and Bartonella phoceensis were detected in the small mammals with the respective detection rates of 12.3%, 5.9% and 4.9%. Rickettsia spp., however, was not detected. This study encountered the presence of both Lyme disease and relapsing fever-related borreliae in small mammals collected from the oil palm plantation study sites. All three microorganisms (Orientia tsutsugamushi, Borrelia spp. and Bartonella phoceensis) were detected in the R. tanezumi R3 mitotype, suggesting that the species is a competent host for multiple microorganisms. Further investigations are warranted to elucidate the relationships between the ectoparasites, the small mammals and the respective pathogens.

Development and Validation of a Protein Array for Detection of Antibodies against the Tick-Borne Pathogen Borrelia miyamotoi

Current serological tests for the emerging tick-borne pathogen Borrelia miyamotoi lack diagnostic accuracy. To improve serodiagnosis, we investigated a protein array simultaneously screening for IgM and IgG reactivity against multiple recombinant B. miyamotoi antigens. The array included six B. miyamotoi antigens: glycerophosphodiester phosphodiesterase (GlpQ), multiple variable major proteins (Vmps), and flagellin. Sera included samples from cases of PCR-proven Borrelia miyamotoi disease (BMD), multiple potentially cross-reactive control groups (including patients with culture-proven Lyme borreliosis, confirmed Epstein-Barr virus, cytomegalovirus, or other spirochetal infections), and several healthy control groups from regions where Ixodes is endemic and regions where it is nonendemic. Based on receiver operating characteristic (ROC) analyses, the cutoff for reactivity per antigen was set at 5 μg/mL for IgM and IgG. The individual antigens demonstrated high sensitivity but relatively low specificity for both IgM and IgG. The best-performing single antigen (GlpQ) showed a sensitivity of 88.0% (95% confidence interval [CI], 78.9 to 93.5) and a specificity of 94.2% (95% CI, 92.7 to 95.6) for IgM/IgG. Applying the previous published diagnostic algorithm-defining seroreactivity as reactivity against GlpQ and any Vmp-revealed a significantly higher specificity of 98.5% (95% CI, 97.6 to 99.2) but a significantly lower sensitivity of 79.5% (95% CI, 69.3 to 87.0) for IgM/IgG compared to GlpQ alone. Therefore, we propose to define seroreactivity as reactivity against GlpQ and any Vmp or flagellin which resulted in a comparable sensitivity of 84.3% (95% CI, 74.7 to 90.8) and a significantly higher specificity of 97.9% (95% CI, 96.9 to 98.7) for IgM/IgG compared to GlpQ alone. In conclusion, we have developed and validated a novel serological tool to diagnose BMD that could be implemented in clinical practice and epidemiological studies. IMPORTANCE This paper describes the protein array as a novel serological test for the diagnosis of Borrelia miyamotoi disease (BMD), by reporting the methodology, the development of a diagnostic algorithm, and its extensive validation. With rising numbers of ticks and tick bites, tick-borne diseases, such as BMD, urgently deserve further societal and medical attention. B. miyamotoi is prevalent in Ixodes ticks across the northern hemisphere. Humans are exposed to, and infected by, B. miyamotoi and develop BMD in Asia, in North America, and to a lesser extent in Europe. However, the burden of infection and disease remains largely unknown, due to the noncharacteristic clinical presentation, together with the lack of awareness and availability of diagnostic tools. With this paper, we offer a novel diagnostic tool which will assist in assessing the burden of disease and could be implemented in clinical care.

Detection of antibodies to <i>B. burgdorferi</i> by enzyme immunoassay in patients with Lyme borreliosis

The detection of antibodies to borrelia by enzyme immunoassay (ELISA) significantly depends on the time from the onset of the disease.

Purpose: analysis of the results of antibodies determination to borrelia by ELISA in children and adults with Lyme borreliosis (LB) at various periods from the onset of the disease.

Material and methods. We conducted a retrospective, non-randomized, single-center cohort study, based on the analysis of data from 178 outpatient records of patients with a confirmed diagnosis of LB and the presence of antibody detection results by ELISA. Immunological confirmation of the diagnosis of LB was carried out by using ELISA and western blot test systems registered in the territory of the Russian Federation for the separate determination of immunoglobulins to Borrelia burgdorferi antigens of classes M and G. Results. When counting from the date of the onset of the disease, IgM and/or IgG were determined in 76% of patients at 4-6 weeks, and starting from the 7th week – in 95%. When counting from the date of tick bite, IgG with or without IgM was determined in 83% of patients starting from 7th week. At the same time, a significantly large proportion of seronegative patients among children was revealed. We have clarified the duration of antibody persistence after antibacterial therapy. In the interval from 1 to 6 months, antibodies are detected in 73% of patients. For a period of 6 months or more, antibodies can be detected in 42% of patients.

Conclusion. The optimal time for detecting antibodies from the disease onset is 4-6 weeks. Antibodies after antibiotic therapy can persist for a long time, in a third of patients up to 6 months or more.

The first detection of relapsing fever spirochete Borrelia miyamotoi in Ixodes ricinus ticks from the northeast Czech Republic

Borrelia miyamotoi, a relapsing fever spirochete, is considered a human pathogen. Knowledge of this borrelia is currently limited. Data about its potential impact on public health, circulation in nature, or its occurrence in natural environments are insufficient. For our study, a total of 505 questing Ixodes ricinus ticks (337 nymphs, 85 females and 83 males) from Hradec Králové Region in the Czech Republic were collected. Additionally, 160 winged Lipoptena deer keds from Hradec Králové Region, from Pardubice Region, Czech Republic, and from one location in western Slovakia were collected. The presence of B. miyamotoi in ticks and deer keds was determined using polymerase chain reaction (PCR) targeting a gene encoding glycerophosphodiester phosphodiesterase (glpQ), antigenic protein specific to the relapsing fever spirochetes. Borrelia miyamotoi was identified in six nymphs and four females of I. ricinus ticks. The overall prevalence was 2%. None of the examined Lipoptena specimens were found to be infected. Although no human case of infection with B. miyamotoi has been reported in the Czech Republic yet, this spirochete is widespread in ticks, and therefore the risk of human infection exists.

Prevalence and clinical manifestation of Borrelia miyamotoi in Ixodes ticks and humans in the northern hemisphere: a systematic review and meta-analysis

BACKGROUND

Various studies have evaluated the infection of Ixodes ticks and humans with the relapsing fever spirochaete Borrelia miyamotoi. However, to our knowledge, the prevalence of infection and disease has not been assessed systematically. We aimed to examine the prevalence of B miyamotoi in Ixodes ticks and humans, and the disease it can cause, in the northern hemisphere.

METHODS

For this systematic review and meta-analysis, we searched PubMed and Web of Science up to March 1, 2021. Studies assessing Ixodes tick infection published since Jan 1, 2011 were eligible, whereas no time limitation was placed on reports of human infection and disease. We extracted B miyamotoi test positivity ratios and used a random-effects model to calculate estimated proportions of infected ticks, infected humans, and human disease with 95% CI. This study was registered with PROSPERO, CRD42021268996.

FINDINGS

We identified 730 studies through database searches and 316 additional studies that referenced two seminal articles on B miyamotoi. Of these 1046 studies, 157 were included in the review, reporting on 165 637 questing ticks, 45 608 unique individuals, and 504 well described cases of B miyamotoi disease in humans. In ticks, the highest prevalence of B miyamotoi was observed in Ixodes persulcatus (2·8%, 95% CI 2·4-3·1) and the lowest in Ixodes pacificus (0·7%, 0·6-0·8). The overall seroprevalence in humans was 4·4% (2·8-6·3), with significantly (p<0·0001) higher seroprevalences in the high-risk group (4·6%, 2·6-7·1), participants with confirmed or suspected Lyme borreliosis (4·8%, 1·8-8·8), and individuals suspected of having a different tick-borne disease (11·9%, 5·6-19·9) than in healthy controls (1·3%, 0·4-2·8). Participants suspected of having a different tick-borne disease tested positive for B miyamotoi by PCR significantly more often than did the high-risk group (p=0·025), with individuals in Asia more likely to test positive than those in the USA (odds ratio 14·63 [95% CI 2·80-76·41]).

INTERPRETATION

B miyamotoi disease should be considered an emerging infectious disease, especially in North America and Asia. Prospective studies and increased awareness are required to obtain further insights into the burden of disease.

FUNDING

ZonMW and the European Regional Development Fund (Interreg).

When to Think About Other Borreliae:: Hard Tick Relapsing Fever (Borrelia miyamotoi), Borrelia mayonii, and Beyond

In North America, several hard tick-transmitted Borrelia species other than Borrelia burgdorferi cause human disease, including Borrelia miyamotoi, Borrelia mayonii, and possibly Borrelia bissettii. Due to overlapping clinical syndromes, nonspecific tickborne disease (TBD) testing strategies, and shared treatment approaches, infections with these lesser known Borrelia are likely under-reported. In this article, we describe the epidemiology, clinical manifestations, diagnosis, and treatment of these less common Borrelia pathogens.

A comparison of horizontal and transovarial transmission efficiency of Borrelia miyamotoi by Ixodes scapularis

Borrelia miyamotoi is a relapsing fever spirochete carried by Ixodes spp. ticks throughout the northern hemisphere. The pathogen is acquired either transovarially (vertically) or horizontally through blood-feeding and passed transtadially across life stages. Despite these complementary modes of transmission, infection prevalence of ticks with B. miyamotoi is typically low (<5%) in natural settings and the relative contributions of the two transmission modes have not been studied extensively. Horizontal transmission of B. miyamotoi (strain CT13-2396 or wild type strain) was initiated using infected Ixodes scapularis larvae or nymphs to expose rodents, which included both the immunocompetent CD-1 laboratory mouse (Mus musculus) and a natural reservoir host, the white-footed mouse (Peromyscus. leucopus), to simulate natural enzootic transmission. Transovarial transmission was evaluated using I. scapularis exposed to B. miyamotoi as either larvae or nymphs feeding on immunocompromised SCID mice (M. musculus) and subsequently fed as females on New Zealand white rabbits. Larvae from infected females were qPCR-tested individually to assess transovarial transmission rates. Tissue tropism of B. miyamotoi in infected ticks was demonstrated using in situ hybridization. Between 1 and 12% of ticks were positive (post-molt) for B. miyamotoi after feeding on groups of CD-1 mice or P. leucopus with evidence of infection, indicating that horizontal transmission was inefficient, regardless of whether infected larvae or nymphs were used to challenge the mice. Transovarial transmission occurred in 7 of 10 egg clutches from infected females. Filial infection prevalence in larvae ranged from 3 to 100% (median 71%). Both larval infection prevalence and spirochete load were highly correlated with maternal spirochete load. Spirochetes were disseminated throughout the tissues of all three stages of unfed ticks, including the salivary glands and female ovarian tissue. The results indicate that while multiple transmission routes contribute to enzootic maintenance of B. miyamotoi, transovarial transmission is likely to be the primary source of infected ticks and therefore risk assessment and tick control strategies should target adult female ticks.

Borrelia miyamotoi Meningoencephalitis in an Immunocompetent Patient

Borrelia miyamotoi is an underdiagnosed cause of tick-borne illness in endemic regions and, in rare cases, causes neurological disease in immunocompetent patients. Here, we present a case of serologically confirmed Borrelia miyamotoi meningoencephalitis in an otherwise healthy patient who rapidly improved following initiation of antibiotic therapy.

Abundance of Ixodes ricinus Ticks (Acari: Ixodidae) and the Diversity of Borrelia Species in Northeastern Poland

Monitoring the abundance of ticks and the prevalence of pathogens in ticks is an important activity in assessing the risk of tick-borne diseases and helps to develop preventive measures. This study aimed to estimate the density of Ixodes ricinus, the prevalence of Borrelia species, and their diversity in northeastern Poland. The overall mean I. ricinus density was 9.7 ticks/100 m². There were no differences between years, subregions, or habitats of study. The Borrelia infection rate was higher in females (22.6%) and males (14.3%) than in nymphs 5.5% (MIR). The most infected ticks came from the eastern subregion (10.1%) where the incidence of borreliosis among the inhabitants was over 20% higher than in the other subregions. In the infected ticks, B. afzelii (38.3%) and B. garinii (34.5%) were predominant. B. bavariensis was confirmed in I. ricinus in Poland for the first time. The most polymorphic was B. garinii. B. miyamotoi (belonged to the European type) was identified as a mono-infection in 0.9% of ticks and in 1.5% as a co-infection with B. afzelii and with B. garinii. Besides the risk of borreliosis and co-infections with different Borrelia species, physicians should also be aware of B. miyamotoi infections among patients.

Prevalence of Bacterial and Protozoan Pathogens in Ticks Collected from Birds in the Republic of Moldova

Epidemiological knowledge on pathogens in ticks feeding on birds in Moldova is scarce. To reduce this gap of information, a total of 640 migrating and native birds of 40 species were caught from 2012 to 2015 and examined for the presence of ticks in the Republic of Moldova. Altogether, 262 ticks belonging to five tick species (Ixodes ricunus n = 245, Ixodes frontalis n = 12, Haemaphysalis punctata n = 2, Hyalomma marginatum n = 2 (only males), Dermacentor marginatus n = 1) were collected from 93 birds. Of these ticks, 250 (96%) were at the stage of a nymph and 9 at the stage of a larva (3%). One imago of I. frontalis and two imagoes of Hy. marginatum were found. Generally, ticks infested 14.1% of the assessed birds belonging to 12 species. DNA was extracted from individual ticks with subsequent PCR targeting Rickettsia spp., Borrelia spp. in general, as well as relapsing fever-associated Borrelia spp., in particular, Anaplasma phagocytophilum, Neoehrlichia mikurensis, Babesia spp. and Coxiella burnetii. The bird species Turdus merula showed the heaviest infestation with ticks and the highest incidence of infected ticks. Altogether, 32.8% of the assessed ticks (n = 86) were positive for one of the pathogens. DNA of Borrelia spp. was found in 15.2% (40/262) of the investigated ticks; in 7.6% of ticks (20/262), DNA of rickettsiae was detected; 6.9% (18/262) of the ticks were positive for A. phagocytophilum DNA; in 1.5% of the ticks (4/262), DNA of Neoehrlichia mikurensis was detected, followed by 1.5% (4/262) Babesia microti and 1.5% (4/262) Borrelia miyamotoi. Within the B. burgdorferi complex, B. garinii (n = 36) was largely predominant, followed by B. valaisiana (n = 2) and B. lusitaniae (n = 2). Among the detected Rickettsia spp., R. monacensis (n = 16), R. helvetica (n = 2) and R. slovaca (n = 1) were identified. In conclusion, the study provided some new information on the prevalence of ticks on birds in Moldova, as well as the presence of DNA of pathogens in the ticks. By doing so, it provided an additional piece in the puzzle of the global epidemiology of tick-transmitted infectious diseases from a geographic side from where respective surveillance data are scarce.

Prevalence of Tick-Borne Pathogens in Questing Ixodes ricinus and Dermacentor reticulatus Ticks Collected from Recreational Areas in Northeastern Poland with Analysis of Environmental Factors

Ticks, such as Ixodes ricinus and Dermacentor reticulatus, act as vectors for multiple pathogens posing a threat to both human and animal health. As the process of urbanization is progressing, those arachnids are being more commonly encountered in urban surroundings. In total, 1112 I. ricinus (n = 842) and D. reticulatus (n = 270) ticks were collected from several sites, including recreational urban parks, located in Augustów and Białystok, Poland. Afterwards, the specimens were examined for the presence of Borrelia spp., Babesia spp., Anaplasma phagocytophilum, Rickettsia spp., Bartonella spp., and Coxiella burnetii using the PCR method. Overall obtained infection rate reached 22.4% (249/1112). In total, 26.7% (225/842) of I. ricinus was infected, namely with Borrelia spp. (25.2%; 212/842), Babesia spp. (2.0%; 17/842), and A. phagocytophilum (1.2%; 10/842). Among D. reticulatus ticks, 8.9% (24/270) were infected, specifically with Babesia spp. (7.0%; 19/270), A. phagocytophilum (1.1%; 3/270), and Borrelia burgdorferi s.l. (0.7%; 2/270). No specimen tested positively for Rickettsia spp., Bartonella spp., or Coxiella burnetii. Co-infections were detected in 14 specimens. Results obtained in this study confirm that I. ricinus and D. reticulatus ticks found within the study sites of northeastern Poland are infected with at least three pathogens. Evaluation of the prevalence of pathogens in ticks collected from urban environments provides valuable information, especially in light of the growing number of tick-borne infections in humans and domesticated animals.

Anaplasma phagocytophilum infection rates in questing and host-attached ticks: a global systematic review and meta-analysis

Anaplasma phagocytophilum causes a multi-organ non-specific febrile illness referred to as human granulocytic anaplasmosis. The epidemiologic risk of the pathogen is underestimated despite human encroachment into the natural habitats of ticks. In this study, we performed a systematic review and meta-analysis to determine the global infection rates and distribution of A. phagocytophilum in tick vectors. We pooled data using the random-effects model, assessed individual study quality using the Joanna Briggs Institute critical appraisal instrument for prevalence studies and determined heterogeneity and across study bias using Cochran's Q-test and Egger's regression test respectively. A total of 126 studies from 33 countries across 4 continents reported A. phagocytophilum estimated infection rate of 4.76% (9453/174,967; 95% CI: 3.96, 5.71). Estimated IRs across sub-groups varied significantly (p <0.05) with a range of 1.95 (95% CI: 0.63, 5.86) to 7.15% (95% CI: 5.31, 9.56). Country-based IRs ranged between 0.42 (95% CI: 0.22, 0.80) in Belgium and 37.54% (95% CI: 0.72, 98.03) in Norway. The highest number of studies on A. phagocytophilum were in Europe (82/126) by continent and the USA (33/126) by country. The risk of transmitting this pathogens from ticks to animals and humans exist and therefore, we recommend the use of chemical and biological control measures as well as repellents and protective clothing by occupationally exposed individuals to curtail further transmission of the pathogen to humans and animals.

Frequency and Geographic Distribution of Borrelia miyamotoi, Borrelia burgdorferi, and Babesia microti Infections in New England Residents

BACKGROUND

Borrelia miyamotoi is a relapsing fever spirochete that relatively recently has been reported to infect humans. It causes an acute undifferentiated febrile illness that can include meningoencephalitis and relapsing fever. Like Borrelia burgdorferi, it is transmitted by Ixodes scapularis ticks in the northeastern United States and by Ixodes pacificus ticks in the western United States. Despite reports of clinical cases from North America, Europe, and Asia, the prevalence, geographic range, and pattern of expansion of human B. miyamotoi infection are uncertain. To better understand these characteristics of B. miyamotoi in relation to other tickborne infections, we carried out a cross-sectional seroprevalence study across New England that surveyed B. miyamotoi, B. burgdorferi, and Babesia microti infections.

METHODS

We measured specific antibodies against B. miyamotoi, B. burgdorferi, and B. microti among individuals living in 5 New England states in 2018.

RESULTS

Analysis of 1153 serum samples collected at 11 catchment sites showed that the average seroprevalence for B. miyamotoi was 2.8% (range, 0.6%-5.2%), which was less than that of B. burgdorferi (11.0%; range, 6.8%-15.6%) and B. microti (10.0%; range, 6.5%-13.6%). Antibody screening within county residence in New England showed varying levels of seroprevalence for these pathogens but did not reveal a vectoral geographical pattern of distribution.

CONCLUSIONS

Human infections caused by B. miyamotoi, B. burgdorferi, and B. microti are widespread with varying prevalence throughout New England.

Seminar Lessons: Infectious Diseases Associated with and Causing Disaster

Disasters such as the magnitude-9 Great East Japan Earthquake occur periodically. We considered this experience while developing measures against a predicted earthquake in the Nankai Trough. This report includes a summary of 10 disastrous infectious diseases for which a countermeasures seminar was held. Thirty-five speakers from twenty-one organizations performed the lectures. Besides infectious diseases, conference topics also included disaster prevention and mitigation methods. In addition, the development of point-of-care tests, biomarkers for diagnosis, and severity assessments for infectious diseases were introduced, along with epidemics of infectious diseases affected by climate. Of the 28 pathogens that became a hot topic, 17 are viruses, and 14 out of these 17 (82%) are RNA viruses. Of the 10 seminars, the last 2 targeted only COVID-19. It was emphasized that COVID-19 is not just a disaster-related infection but a disaster itself. The first seminar on COVID-19 provided immunological and epidemiological knowledge and commentary on clinical practices. During the second COVID-19 seminar, vaccine development, virological characteristics, treatment of respiratory failure, biomarkers, and human genetic susceptibility for infectious diseases were discussed. Conducting continuous seminars is important for general infectious controls.

Tick borne relapsing fever - a systematic review and analysis of the literature

Tick borne relapsing fever (TBRF) is a zoonosis caused by various Borrelia species transmitted to humans by both soft-bodied and (more recently recognized) hard-bodied ticks. In recent years, molecular diagnostic techniques have allowed to extend our knowledge on the global epidemiological picture of this neglected disease. Nevertheless, due to the patchy occurrence of the disease and the lack of large clinical studies, the knowledge on several clinical aspects of the disease remains limited. In order to shed light on some of these aspects, we have systematically reviewed the literature on TBRF and summarized the existing data on epidemiology and clinical aspects of the disease. Publications were identified by using a predefined search strategy on electronic databases and a subsequent review of the reference lists of the obtained publications. All publications reporting patients with a confirmed diagnosis of TBRF published in English, French, Italian, German, and Hungarian were included. Maps showing the epidemiogeographic mosaic of the different TBRF Borrelia species were compiled and data on clinical aspects of TBRF were analysed. The epidemiogeographic mosaic of TBRF is complex and still continues to evolve. Ticks harbouring TBRF Borrelia have been reported worldwide, with the exception of Antarctica and Australia. Although only molecular diagnostic methods allow for species identification, microscopy remains the diagnostic gold standard in most clinical settings. The most suggestive symptom in TBRF is the eponymous relapsing fever (present in 100% of the cases). Thrombocytopenia is the most suggestive laboratory finding in TBRF. Neurological complications are frequent in TBRF. Treatment is with beta-lactams, tetracyclines or macrolids. The risk of Jarisch-Herxheimer reaction (JHR) appears to be lower in TBRF (19.3%) compared to louse-borne relapsing fever (LBRF) (55.8%). The overall case fatality rate of TBRF (6.5%) and LBRF (4-10.2%) appears to not differ. Unlike LBRF, where perinatal fatalities are primarily attributable to abortion, TBRF-related perinatal fatalities appear to primarily affect newborns.

Corneal Confocal Microscopy Findings in Neuro Lyme Disease: A Case Report

Neuro Lyme disease is caused by several bacteriae of the Borreliaceae family, such as Borrelia Miyamotoi. In late stages of illness, patients with Lyme disease may develop chronic neurologic symptoms such as cognitive disturbances or small fiber peripheral neuropathy. Confocal microscopy is a non-invasive method designed to evaluate the human cornea in vivo. Thus, all the corneal layers, including the cells and the sub-basal nerve plexus, can be easily visualized and analyzed. This is the first report of the morphology of small-fiber peripheral neuropathy analyzed by confocal microscopy in a patient diagnosed of neuro Lyme disease. The decrease in the number of unmyelinated sub-basal nerve fibers with abundant presence of dendritic cells (DC) in comparison with healthy corneas strongly supports the diagnosis of small fiber peripheral neuropathy in a case of neuroborreliosis disease.

Borrelia burgdorferi and Borrelia miyamotoi in Atlantic Canadian wildlife

Borrelia burgdorferi and Borrelia miyamotoi are tick-vectored zoonotic pathogens maintained in wildlife species. Tick populations are establishing in new areas globally in response to climate change and other factors. New Brunswick is a Canadian maritime province at the advancing front of tick population establishment and has seen increasing numbers of ticks carrying B. burgdorferi, and more recently B. miyamotoi. Further, it is part of a region of Atlantic Canada with wildlife species composition differing from much of continental North America and little information exists as to the presence and frequency of infection of Borrelia spp. in wildlife in this region. We used a citizen science approach to collect a wide range of animals including migratory birds, medium-sized mammals, and small mammals. In total we tested 339 animals representing 20 species for the presence of B. burgdorferi and B. miyamotoi. We have developed new nested PCR primers and a protocol with excellent specificity for detecting both of these Borrelia species, both single and double infections, in tissues and organs of various wildlife species. The positive animals were primarily small non-migratory mammals, approximately twice as many were infected with B. burgdorferi than B. miyamotoi and one animal was found infected with both. In addition to established reservoir species, the jumping mouse (Napaeozapus insignis) was found frequently infected; this species had the highest infection prevalence for both B. burgdorferi and B. miyamotoi and has not previously been identified as an important carrier for either Borrelia species. Comprehensive testing of tissues found that all instances of B. burgdorferi infection were limited to one tissue within the host, whereas two of the five B. miyamotoi infections were diffuse and found in multiple systems. In the one coinfected specimen, two fetuses were also recovered and found infected with B. miyamotoi. This presumptive transplacental transmission suggests that vertical transmission in mammals is possible. This finding implies that B. miyamotoi could rapidly spread into wildlife populations, as well as having potential human health implications.

Human Borrelia miyamotoi infection: A cause of persistent fever and severe hyperthermia in New England

An adult male presented to a hospital in southwestern Connecticut with tachypnea, generalized weakness, altered mental status, and relapsing fever with maximum recorded temperature of 106 °F. He required active cooling, antipyretic therapy, broad spectrum antibiotics, and intubation for airway protection after an episode of emesis. Initial laboratory and imaging workup were remarkable for elevated inflammatory markers, acute kidney injury, and bilateral lower lobe infiltrates. Further workup with lumbar puncture and electroencephalography were unrevealing. Extensive testing for causes of relapsing fever including tickborne diseases revealed that the patient was seropositive for Borrelia miyamotoi. Notably, he had no rash, and workup found no evidence of coinfection by other Borrelia, Ehrlichia or Anaplasma species. This case illustrates the need for clinicians to test for tick-borne diseases when evaluating for cases of relapsing fever in New England and is among the first case reports to demonstrate Borrelia miyamotoi as a cause of severe pyrexia.

Community engaged tick surveillance and tickMAP as a public health tool to track the emergence of ticks and tick-borne diseases in New York

A community engaged passive surveillance program was utilized to acquire ticks and associated information throughout New York state. Ticks were speciated and screened for several tick-borne pathogens. Of these ticks, only I. scapularis was commonly infected with pathogens of human relevance, including B. burgdorferi, B. miyamotoi, A. phagocytophilum, B. microti, and Powassan virus. In addition, the geographic and temporal distribution of tick species and pathogens was determined. This enabled the construction of a powerful visual analytical mapping tool, tickMAP to track the emergence of ticks and tick-borne pathogens in real-time. The public can use this tool to identify hot-spots of disease emergence, clinicians for supportive evidence during differential diagnosis, and researchers to better understand factors influencing the emergence of ticks and tick-borne diseases in New York. Overall, we have created a community-engaged tick surveillance program and an interactive visual analytical tickMAP that other regions could emulate to provide real-time tracking and an early warning for the emergence of tick-borne diseases.