Projecting the potential distribution of ticks in China under climate and land use change

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.

Impact of climate change on the geographical distribution of ticks of public health significance in Colombia: Amblyomma ovale (Ixodida: Ixodidae), the Amblyomma maculatum (Ixodida: Ixodidae) complex and the Amblyomma cajennense (Ixodida: Ixodidae) complex

Ticks of the Amblyomma maculatum (Ixodida Ixodidae) complex, the Amblyomma cajennense (Ixodida Ixodidae) complex and Amblyomma ovale (Ixodida Ixodidae) are known to transmit various Rickettsia species in Colombia, but their exact distribution is unknown. We built several models based on current climate and projected future climate changes using a maximum entropy approach. A total of 314 records of the A. cajennense complex (65.9%; n = 207), A. ovale (22.9%; n = 72), and the A. maculatum complex (11.1%; n = 35) were obtained. Amblyomma ovale has a current distribution in the Pacific, Caribbean and Andean regions and could be potentially found in the Amazon. Amblyomma maculatum has a current distribution in the Andean and could potentially be found in the Caribbean and Orinoco regions. Amblyomma mixtum can be found near the Caribbean Sea and in the Pacific region, and A. patinoi is likely to be found in the Andean region and the Caribbean. In 2070, it will be possible to find an expansion of A. ovale and A. maculatum and a decrease of A. mixtum and A. patinoi. The variables that best predict the distribution of these species are isothermality (small fluctuations in temperature) and annual precipitation. Amblyomma cajennense s.l and A. ovale, A. cajennese s.l and A. patinoi, as well as A. maculatum and A. patinoi, have an important environmental sympatry. Epidemiological and acarological surveillance is crucial to investigate rickettsiosis caused by R. parkeri in A. ovale regions, by R. rickettsii in A. patinoi and A. mixtum areas, and by R. parkeri s.s in A. maculatum regions.

Global epidemiology of severe fever with thrombocytopenia syndrome virus in human and animals: a systematic review and meta-analysis

Background

Since the initial identification of the Severe Fever with Thrombocytopenia Syndrome (SFTS) in ticks in rural areas of China in 2009, the virus has been increasingly isolated from a diverse array of hosts globally, exhibiting a rising trend in incidence. This study aims to conduct a systematic analysis of the temporal and spatial distribution of SFTS cases, alongside an examination of the infection rates across various hosts, with the objective of addressing public concerns regarding the spread and impact of the disease.

Methods

In this systematic review and meta-analysis, an exhaustive search was conducted across multiple databases, including PubMed, Web of Science, Embase, and Medline, CNKI, WanFang, and CQVIP. The literature search was confined to publications released between January 1, 2009, and May 29, 2023. The study focused on collating data pertaining to animal infections under natural conditions and human infection cases reported. Additionally, species names were unified using the National Center for Biotechnology Information (NCBI) database. The notification rate, notification death rate, case fatality rate, and infection rates (or MIR) were assessed for each study with available data. The proportions were pooled using a generalized linear mixed-effects model (GLMM). Meta-regressions were conducted for subgroup analysis. This research has been duly registered with PROSPERO, bearing the registration number CRD42023431010.

Findings

We identified 5492 studies from database searches and assessed 238 full-text studies for eligibility, of which 234 studies were included in the meta-analysis. For human infection data, the overall pooled notification rate was 18.93 (95% CI 17.02-21.05) per ten million people, the overall pooled notification deaths rate was 3.49 (95% CI 2.97-4.10) per ten million people, and the overall pooled case fatality rate was 7.80% (95% CI 7.01%-8.69%). There was an increasing trend in notification rate and deaths rate, while the case fatality rate showed a significant decrease globally. Regarding animal infection data, among 94 species tested, 48 species were found to carry positive nucleic acid or antibodies. Out of these, 14 species were classified under Arthropoda, while 34 species fell under Chordata, comprising 27 Mammalia and 7 Aves.

Interpretation

This systematic review and meta-analysis present the latest global report on SFTS. In terms of human infections, notification rates and notification deaths rates are on the rise, while the case fatality rate has significantly decreased. More SFTSV animal hosts have been discovered than before, particularly among birds, indicating a potentially broader transmission range for SFTSV. These findings provide crucial insights for the prevention and control of SFTS on a global scale.

Funding

None.

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

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

Tick species diversity and potential distribution alternation of dominant ticks under different climate scenarios in Xinjiang, China

Ticks are a hematophagous parasite and a vector of pathogens for numerous human and animal diseases of significant importance. The expansion of tick distribution and the increased risk of tick-borne diseases due to global climate change necessitates further study of the spatial distribution trend of ticks and their potential influencing factors. This study constructed a dataset of tick species distribution in Xinjiang for 60 years based on literature database retrieval and historical data collection (January 1963-January 2023). The distribution data were extracted, corrected, and deduplicated. The dominant tick species were selected for analysis using the MaxEnt model to assess their potential distribution in different periods under the current and BCC-CSM2.MR mode scenarios. The results indicated that there are eight genera and 48 species of ticks in 108 cities and counties of Xinjiang, with Hyalomma asiaticum, Rhipicephalus turanicus, Dermacentor marginatus, and Haemaphysalis punctatus being the top four dominant species. The MaxEnt model analysis revealed that the suitability areas of the four dominant ticks were mainly distributed in the north of Xinjiang, in areas such as Altay and Tacheng Prefecture. Over the next four periods, the medium and high suitable areas within the potential distribution range of the four tick species will expand towards the northwest. Additionally, new suitability areas will emerge in Altay, Changji Hui Autonomous Prefecture, and other local areas. The 60-year tick dataset in this study provides a map of preliminary tick distribution in Xinjiang, with a diverse array of tick species and distribution patterns throughout the area. In addition, the MaxEnt model revealed the spatial change characteristics and future distribution trend of ticks in Xinjiang, which can provide an instrumental data reference for tick monitoring and tick-borne disease risk prediction not only in the region but also in other countries participating in the Belt and Road Initiative.

The current distribution of tick species in Inner Mongolia and inferring potential suitability areas for dominant tick species based on the MaxEnt model

BACKGROUND

Ticks are known to transmit a wide range of diseases, including those caused by bacteria, viruses, and protozoa. The expansion of tick habitats has been intensified in recent years due to various factors such as global warming, alterations in microclimate, and human activities. Consequently, the probability of human exposure to diseases transmitted by ticks has increased, leading to a higher degree of risk associated with such diseases.

METHODS

In this study, we conducted a comprehensive review of domestic and international literature databases to determine the current distribution of tick species in Inner Mongolia. Next, we employed the MaxEnt model to analyze vital climatic and environmental factors influencing dominant tick distribution. Subsequently, we predicted the potential suitability areas of these dominant tick species under the near current conditions and the BCC-CSM2.MR model SSP245 scenario for the future periods of 2021-2040, 2041-2060, 2061-2080, and 2081-2100.

RESULTS

Our study revealed the presence of 23 tick species from six genera in Inner Mongolia, including four dominant tick species (Dermacentor nuttalli, Ixodes persulcatus, Dermacentor silvarum, and Hyalomma asiaticum). Dermacentor nuttalli, D. silvarum, and I. persulcatus are predominantly found in regions such as Xilin Gol and Hulunbuir. Temperature seasonality (Bio4), elevation (elev), and precipitation seasonality (Bio15) were the primary variables impacting the distribution of three tick species. In contrast, H. asiaticum is mainly distributed in Alxa and Bayannur and demonstrates heightened sensitivity to precipitation and other climatic factors. Our modeling results suggested that the potential suitability areas of these tick species would experience fluctuations over the four future periods (2021-2040, 2041-2060, 2061-2080, and 2081-2100). Specifically, by 2081-2100, the centroid of suitable habitat for D. nuttalli, H. asiaticum, and I. persulcatus was predicted to shift westward, with new suitability areas emerging in regions such as Chifeng and Xilin Gol. The centroid of suitable habitat for H. asiaticum will move northeastward, and new suitability areas are likely to appear in areas such as Ordos and Bayannur.

CONCLUSIONS

This study provided a comprehensive overview of the tick species distribution patterns in Inner Mongolia. Our research has revealed a significant diversity of tick species in the region, exhibiting a wide distribution but with notable regional disparities. Our modeling results suggested that the dominant tick species' suitable habitats will significantly expand in the future compared to their existing distribution under the near current conditions. Temperature and precipitation are the primary variables influencing these shifts in distribution. These findings can provide a valuable reference for future research on tick distribution and the surveillance of tick-borne diseases in the region.

Infectious Disease Sensitivity to Climate and Other Driver-Pressure Changes: Research Effort and Gaps for Lyme Disease and Cryptosporidiosis

Climate sensitivity of infectious diseases is discussed in many studies. A quantitative basis for distinguishing and predicting the disease impacts of climate and other environmental and anthropogenic driver-pressure changes, however, is often lacking. To assess research effort and identify possible key gaps that can guide further research, we here apply a scoping review approach to two widespread infectious diseases: Lyme disease (LD) as a vector-borne and cryptosporidiosis as a water-borne disease. Based on the emerging publication data, we further structure and quantitatively assess the driver-pressure foci and interlinkages considered in the published research so far. This shows important research gaps for the roles of rarely investigated water-related and socioeconomic factors for LD, and land-related factors for cryptosporidiosis. For both diseases, the interactions of host and parasite communities with climate and other driver-pressure factors are understudied, as are also important world regions relative to the disease geographies; in particular, Asia and Africa emerge as main geographic gaps for LD and cryptosporidiosis research, respectively. The scoping approach developed and gaps identified in this study should be useful for further assessment and guidance of research on infectious disease sensitivity to climate and other environmental and anthropogenic changes around the world.

Crimean-Congo hemorrhagic fever virus in Central, Eastern, and South-eastern Asia

Crimean-Congo hemorrhagic fever (CCHF), caused by Crimean-Congo hemorrhagic fever virus (CCHFV), is endemic in Africa, Asia, and Europe, but CCHF epidemiology and epizootiology is only rudimentarily defined for most regions. Here we summarize what is known about CCHF in Central, Eastern, and South-eastern Asia. Searching multiple international and country-specific databases using a One Health approach, we defined disease risk and burden through identification of CCHF cases, anti-CCHFV antibody prevalence, and CCHFV isolation from vector ticks. We identified 2313 CCHF cases that occurred in 1944-2021 in the three examined regions. Central Asian countries reported the majority of cases (2,026). In Eastern Asia, China was the only country that reported CCHF cases (287). In South-eastern Asia, no cases were reported. Next, we leveraged our previously established classification scheme to assign countries to five CCHF evidence levels. Six countries (China, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan) were assigned to level 1 or level 2 based on CCHF case reports and the maturity of the countries' surveillance systems. Two countries (Mongolia and Myanmar) were assigned to level 3 due to evidence of CCHFV circulation in the absence of reported CCHF cases. Thirteen countries in Eastern and South-eastern Asia were categorized in levels 4 and 5 based on prevalence of CCHFV vector ticks. Collectively, this paper describes the past and present status of CCHF reporting to inform international and local public-health agencies to strengthen or establish CCHFV surveillance systems and address shortcomings.

Tick maps on the virtual globe: First results using the example of Dermacentor reticulatus

Digital maps, particularly displayed on virtual globes, will represent the most important source of geographical knowledge in the future. The best known of these virtual globes is Google Earth, whose use in teaching at schools and universities is now common practice. As the first result of a series of forthcoming digital tick maps, the worldwide distribution of the marsh tick Dermacentor reticulatus is shown on Google Earth. For this purpose, various distribution maps of D. reticulatus were compiled, including digitized expert maps and a map of suitable habitats compiled with a species distribution model (SDM). A random forest model that estimates suitable habitats by combining information from tick observations, bioclimatic variables, altitude, and land cover was chosen for the latter. In the Google Earth application, the following maps can be selected: a historical expert map, a current expert map, a SDM predicted habitat suitability map, a combined expert-habitat suitability map (considered to be the best representation of the current distribution of D. reticulatus), and a map of rasterized tick locations. Users can overlay these maps according to their own requirements or combine it with other Google Earth content. For example, a comparison of the historical with the current expert map shows the spread of D. reticulatus over the past few decades. Additionally, high-resolution city maps of Bilbao (Spain), Grenoble (France), Berlin (Germany), Wrocław (Poland), Budapest (Hungary), Bucharest (Romania), and Tomsk (Russia) demonstrate the urban distribution of D. reticulatus in public parks, fallow land, and recreational areas. The Google Earth application, developed using the Keyhole Markup Language (KML), also contains fact sheets on biology, ecology, seasonal activity, and vector competence of D. reticulatus. This information has been prepared in a compact and easily understandable way for the target group, i.e. scientists from various disciplines, students, and lay people interested in the geographical distribution of ticks.

Mapping the risk distribution of Borrelia burgdorferi sensu lato in China from 1986 to 2020: a geospatial modelling analysis

Lyme borreliosis, recognized as one of the most important tick-borne diseases worldwide, has been increasing in incidence and spatial extent. Currently, there are few geographic studies about the distribution of Lyme borreliosis risk across China. Here we established a nationwide database that involved Borrelia burgdorferi sensu lato (B. burgdorferi) detected in humans, vectors, and animals in China. The eco-environmental factors that shaped the spatial pattern of B. burgdorferi were identified by using a two-stage boosted regression tree model and the model-predicted risks were mapped. During 1986−2020, a total of 2,584 human confirmed cases were reported in 25 provinces. Borrelia burgdorferi was detected from 35 tick species with the highest positive rates in Ixodes granulatus, Hyalomma asiaticum, Ixodes persulcatus, and Haemaphysalis concinna ranging 20.1%−24.0%. Thirteen factors including woodland, NDVI, rainfed cropland, and livestock density were determined as important drivers for the probability of B. burgdorferi occurrence based on the stage 1 model. The stage 2 model identified ten factors including temperature seasonality, NDVI, and grasslands that were the main determinants used to distinguish areas at high or low-medium risk of B. burgdorferi, interpreted as potential occurrence areas within the area projected by the stage 1 model. The projected high-risk areas were not only concentrated in high latitude areas, but also were distributed in middle and low latitude areas. These high-resolution evidence-based risk maps of B. burgdorferi was first created in China and can help as a guide to future surveillance and control and help inform disease burden and infection risk estimates.

Predicting the northward expansion of tropical lineage Rhipicephalus sanguineus sensu lato ticks in the United States and its implications for medical and veterinary health

The tropical lineage within the Rhipicephalus sanguineus species complex is cause for growing concern in the U.S. based on its prominent role in creating and perpetuating multiple recently identified outbreaks of Rocky Mountain spotted fever in the southwestern United States and northern Mexico. This lineage is undergoing a northward range expansion in the United States, necessitating the need for enhanced surveillance for Rh. sanguineus. To inform more focused surveillance efforts we use species distribution models (SDMs) to predict current (2015–2019) and future (2021–2040) habitat for the tropical lineage. Models using the MaxEnt algorithm were informed using geolocations of ticks genetically confirmed to be of the tropical lineage, for which data on 23 climatic and ecological variables were extracted. Models predicted that suitability was optimal where temperatures are relatively warm and stable, and there is minimal precipitation. This translated into habitat being predicted along much of the coast of southern states including California, Texas, Louisiana, and Florida. Although the endophilic nature of tropical Rh. sanguineus somewhat violates the assumptions of SDMs, our models correctly predicted known locations of this tick and provide a starting point for increased surveillance efforts. Furthermore, we highlight the importance of using molecular methods to distinguish between ticks in the Rh. sanguineus species complex.

Characterization of the complete mitochondrial genome of Ixodes granulatus (Ixodidae) and its phylogenetic implications

Ticks are deemed to be second only to mosquitoes as the most common vector of human infectious diseases worldwide that give rise to human and animal diseases and economic losses to livestock production. Our understanding of the phylogenetic analysis between tick lineages has been restricted by the phylogenetic markers of individual genes. Genomic data research could help advance our understanding of phylogenetic analysis and molecular evolution. Mitochondrial genomic DNA facilitated the phylogenetic analysis of eukaryotes containing ticks. In this study, we sequenced and assembled the circular complete mitogenome information of Ixodes granulatus. The 14,540-bp mitogenome consists of 37 genes, including 13 protein-coding genes (PCGs), two genes for ribosomal RNA (rRNAs), and 22 genes for transfer RNA (tRNAs), and the origin of the L-strand replication region. The directions of the coding strand and component genes in the non-Australasian Ixodes mitochondrial genome were similar to those found in most other Australasian Ixodes, except for the loss of a lengthy control region. The phylogenetic tree based on maximum likelihood (ML) and Bayesian inference (BI) computational algorithms showed that I. granulatus exhibits a close relationship with I. hexagonus and I. ricinus. To our knowledge, this is the first study exploring the complete mitogenome for the species I. granulatus. Our results provide new insights for further research on the evolution, population genetics, systematics, and molecular ecology of ticks.

Global seroprevalence and sociodemographic characteristics of Borrelia burgdorferi sensu lato in human populations: a systematic review and meta-analysis

Introduction

Borrelia burgdorferi sensu lato (Bb) infection, the most frequent tick-transmitted disease, is distributed worldwide. This study aimed to describe the global seroprevalence and sociodemographic characteristics of Bb in human populations.

Methods

We searched PubMed, Embase, Web of Science and other sources for relevant studies of all study designs through 30 December 2021 with the following keywords: ‘Borrelia burgdorferi sensu lato’ AND ‘infection rate’; and observational studies were included if the results of human Bb antibody seroprevalence surveys were reported, the laboratory serological detection method reported and be published in a peer-reviewed journal. We screened titles/abstracts and full texts of papers and appraised the risk of bias using the Cochrane Collaboration-endorsed Newcastle-Ottawa Quality Assessment Scale. Data were synthesised narratively, stratified by different types of outcomes. We also conducted random effects meta-analysis where we had a minimum of two studies with 95% CIs reported. The study protocol has been registered with PROSPERO (CRD42021261362).

Results

Of 4196 studies, 137 were eligible for full-text screening, and 89 (158 287 individuals) were included in meta-analyses. The reported estimated global Bb seroprevalence was 14.5% (95% CI 12.8% to 16.3%), and the top three regions of Bb seroprevalence were Central Europe (20.7%, 95% CI 13.8% to 28.6%), Eastern Asia (15.9%, 95% CI 6.6% to 28.3%) and Western Europe (13.5%, 95% CI 9.5% to 18.0%). Meta-regression analysis showed that after eliminating confounding risk factors, the methods lacked western blotting (WB) confirmation and increased the risk of false-positive Bb antibody detection compared with the methods using WB confirmation (OR 1.9, 95% CI 1.6 to 2.2). Other factors associated with Bb seropositivity include age ≥50 years (12.6%, 95% CI 8.0% to 18.1%), men (7.8%, 95% CI 4.6% to 11.9%), residence of rural area (8.4%, 95% CI 5.0% to 12.6%) and suffering tick bites (18.8%, 95% CI 10.1% to 29.4%).

Conclusion

The reported estimated global Bb seropositivity is relatively high, with the top three regions as Central Europe, Western Europe and Eastern Asia. Using the WB to confirm Bb serological results could significantly improve the accuracy. More studies are needed to improve the accuracy of global Lyme borreliosis burden estimates.

PROSPERO registration number

CRD42021261362.

Detection of Babesia spp. in High Altitude Cattle in Ecuador, Possible Evidence of the Adaptation of Vectors and Diseases to New Climatic Conditions

Background: Babesia species are intraerythrocytic protozoa, distributed in tropical and subtropical areas of the world, causing anemic diseases in many animals, including cattle. This disease, called babesisosis, is transmitted from one animal to another through ticks (Tick Borne-Disease or TBD). On the other hand, Ecuador has a tropical climate that allows the development of the vector Rhipicephalus microplus, and therefore favors the transmission of Babesia spp. in cattle. Methods and principal findings: We determined the presence of Babesia spp. by PCR using 18s ribosomal gene as target (18s PCR) in 20 farms in the area of El Carmen (zone below 300 m above sea level) and 1 farm in Quito (2469 m.a.s.l.). In addition, we analyzed parameters such as age, sex, and packed cell volume (PCV) as explanatory variable associated with the disease. Results: The 18s PCR test showed that 18.94% (14.77% Babesia bovis and 4.17% Babesia bigemina) and 20.28% (14.69% B. bovis and 5.59% B. bigemina) of the cattle were positive for Babesia spp in farms sampled in El Carmen and in Quito, respectively. Age influenced the presence of animals positive for Babesia spp., but sex and PCV did not. The phylogenetic analysis of sequences showed 4 isolates of B. bovis and 3 isolates of B. bigemina in the 2 study zones, with similarities between 99.73 and 100% with other sequences. One B. bovis isolate was similar in the zone of El Carmen and Quito. Conclusion and significance: This work is the first molecular characterization of B. bigemina and B. bovis in Ecuador, and it is also the first evidence of Babesia spp. in cattle in the area of Quito at an altitude of 2469 m.a.s.l., being the highest altitude reported for animals with babesiosis and for the tick R. microplus. Climatic factors as well as mobility of tick-carrying animals without any control allow the presence of Babesiosis outbreaks in new geographical areas.

Identification of Tick-Borne Pathogens and Genotyping of Coxiella burnetii in Rhipicephalus microplus in Yunnan Province, China

Rhipicephalus microplus, a vector that can transmit many pathogens to humans and domestic animals, is widely distributed in Yunnan province, China. However, few reports on the prevalence of tick-borne pathogens (TBPs) in Rh. microplus in Yunnan are available. The aim of this study was to detect TBPs in Rh. microplus in Yunnan and to analyze the phylogenetic characterization of TBPs detected in these ticks. The adult Rh. microplus (n = 516) feeding on cattle were collected. The pooled DNA samples of these ticks were evaluated using metagenomic next-generation sequencing (mNGS) and then TBPs in individual ticks were identified using genus- or group-specific nested polymerase chain reaction (PCR) combined with DNA sequencing assay. As a result, Candidatus Rickettsia jingxinensis (24.61%, 127/516), Anaplasma marginale (13.18%, 68/516), Coxiella burnetii (3.10%, 16/516), and Coxiella-like endosymbiont (CLE) (8.33%, 43/516) were detected. The dual coinfection with Ca. R. jingxinensis and A. marginale and the triple coinfection with Ca. R. jingxinensis, A. marginale, and CLE were most frequent and detected in 3.68% (19/516) and 3.10% (16/516) of these ticks, respectively. The results provide insight into the diversity of TBPs and their coinfections in Rh. microplus in Yunnan province of China, reporting for the first time that C. burnetii had been found in Rh. microplus in China. Multilocus variable number tandem repeat analysis with 6 loci (MLVA-6) discriminated the C. burnetii detected in Rh. microplus in Yunnan into MLVA genotype 1, which is closely related to previously described genotypes found primarily in tick and human samples from different regions of the globe, indicating a potential public health threat posed by C. burnetii in Rh. microplus in Yunnan.