Detection of Amblyomma mixtum (Acari: Ixodidae) in Germany on a Human Traveler Returning From Cuba

The importation of exotic ticks to Germany on infested humans is rarely reported. Here we describe the detection of an Amblyomma mixtum nymph harboring Rickettsia amblyommatis by a tourist returning from a holiday trip to Cuba. Tick infestation may be neglected by tourists. Therefore, careful anamnesis and diagnosis should be carried out when tourists return from tropical and subtropical countries suffering from nonspecific symptoms, such as fever and malaise.

Surveillance for Amblyomma maculatum (Acari: Ixodidae) and Rickettsia parkeri (Rickettsiales: Rickettsiaceae) in the State of Delaware, and Their Public Health Implications

Amblyomma maculatum Koch is the primary vector of Rickettsia parkeri, the etiologic agent of tidewater spotted fever, and can also carry and transmit a variety of other pathogens. This tick historically has been a costly nuisance to livestock owners in the southeastern United States. Over the past 6 yr, A. maculatum has been collected in numbers sufficient to demonstrate their establishment in Kent County, Delaware, and the presence of R. parkeri has been documented. Our goals were to determine the geographic distribution of A. maculatum and R. parkeri in Delaware, and to equate this to relative risk to the public of encountering R. parkeri-infected ticks. We surveyed for ticks in four locations throughout the state from May to August 2019, and found established A. maculatum populations in all three counties. Laboratory analysis of collected specimens by quantitative polymerase chain reaction detected R. parkeri in A. maculatum populations across the state. These results indicate that A. maculatum could present a health risk to inhabitants of the state, and they also historically have posed a risk to the livestock industry, making them an important consideration in the development and implementation of continued tick surveillance efforts and future policies regarding tick management.

Rickettsia spp. Infecting Lone Star Ticks (Amblyomma americanum) (Acari: Ixodidae) in Monmouth County, New Jersey

Tick-borne rickettsiae are undergoing epidemiological changes in the eastern United States while human encounters with lone star ticks (Amblyomma americanum L.) have increased substantially. We used real-time polymerase chain reaction assays to test for three species of spotted fever group rickettsiae (SFGR) (Rickettsiales: Rickettsiaceae) in 1,858 nymphal A. americanum collected from Monmouth County, New Jersey, a coastal county with endemic Lyme disease and established tick surveillance. Out of the 1,858 tested, 465 (25.0%) were infected with Rickettsia amblyommatis Karpathy, a species of undetermined pathogenicity found frequently in A. americanum, while 1/1,858 (0.05%) contained Rickettsia rickettsii Brumpt, the agent of Rocky Mountain spotted fever. No ticks tested positive for mildly pathogenic Rickettsia parkeri Lackman, and no ticks were co-infected with multiple Rickettsia spp. Our results indicate that A. americanum could be involved in transmission of R. rickettsii to humans in New Jersey, albeit rarely. The much higher rates of R. amblyommatis infection are consistent with hypotheses that human sera reacting to this species could contribute to reports of mild SFGR cases.

Tick-borne pathogens in Ixodes ricinus ticks collected from migratory birds in southern Norway

Birds are important hosts for the first life stages of the Ixodes ricinus tick and they can transport their parasites over long distances. The aim of this study was to investigate the prevalence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Neoehrlichia mikurensis and Rickettsia helvetica in ticks collected from migratory birds in Norway. A total of 815 Ixodes ricinus ticks from 216 birds trapped at Lista Bird Observatory in southern Norway during spring and autumn migration in 2008 were analysed by real-time PCR. B. burgdorferi s. l. was the most prevalent pathogen, detected in 6.1% of the ticks. The prevalence of N. mikurensis, A. phagocytophilum and R. helvetica was 1.2%, 0.9% and 0.4% respectively. In addition, one sample (0.1%) was positive for B. miyamotoi. In total, 8.2% of the ticks were infected with at least one pathogen. Co-infection with B. burgdorferi s. l. and N. mikurensis or A. phagocytophilum was found in 6.0% of the infected ticks. Our results show that all the known major tick-borne bacterial pathogens in Norway are subject to transport by migratory birds, potentially allowing spread to new areas. Our study showed a surprisingly high number of samples with PCR inhibition (57%). These samples had been extracted using standard methodology (phenol-chloroform extraction). This illustrates the need for inhibition controls to determine true prevalence rates.

COYOTES (CANIS LATRANS) IN ARIZONA, USA, EXHIBIT IMMUNE AND GENETIC EVIDENCE OF RICKETTSIAL INFECTIONS

Rocky Mountain spotted fever (RMSF), caused by the bacterium Rickettsia rickettsii, was recognized as endemic in Arizona, US after a 2002 outbreak and has since been a public health concern. The brown dog tick (Rhipicephalus sanguineus sensu lato) is the principal vector of this pathogen in Arizona. Domesticated dogs (Canis lupus familiaris) are the tick's main host, so free-roaming dogs in peridomestic areas have been named the primary risk factor for human cases of RMSF. However, the sudden emergence and long-distance dispersal of the pathogen have not been adequately explained, and one possible mechanism could include wildlife. Coyotes (Canis latrans) are wide ranging in Arizona and closely related to dogs, so it is possible that brown dog ticks parasitize coyotes and infect them. Although R. rickettsii is the most severe spotted fever group (SFG) rickettsial pathogen in humans, others occur in Arizona, and antibodies raised against them are cross-reactive, so we more-broadly hypothesized that coyotes in Arizona are exposed to SFG rickettsiae. We collected coyote tissues in spring 2016 and 2017. We tested sera for antibodies to R. rickettsii and found 9% (8/94) of samples were antibody-positive with titers of ≥256. Subsequent quantitative PCR analyses of skin showed evidence for Rickettsia spp. in 2.9% (4/138) of samples. These data suggest that coyotes have a role in the maintenance of SFG rickettsiae in Arizona. Further investigation is warranted to reveal which specific pathogen-vector complexes act on coyotes in the region and whether they represent a risk to human health.

Molecular evidence of the spotted fever group Rickettsiae in ticks from Yunnan Province, Southwest China

Ixodid ticks transmit many obligate intracellular Rickettsial species. Several previous studies have identified Rickettsia species in the northeastern and southern part of China, but few reports on the prevalence of infection of spotted fever group Rickettsiae (SFGR) in ticks in southwest China are available. Here, we investigated SFGR in 394 adult ticks of five species including Dermacentor nuttalli, Dermacentor silvarum, Haemaphysalis longicornis, Ixodes sinensis and Ixodes persulcatus, collected in the border region between China and Burma in Yunnan Province. PCR was used to detect the presence of the citrate synthase (gltA) gene of Rickettsia species. SFGR was found in 12.1% (15/124) of I. persulcatus ticks, which was significantly higher than the 7.2% (7/97) positive D. nuttalli, 5.4% (3/56) D. silvarum, 5.6% (4/72) H. longicornis and 4.4 (2/45) I. sinensis. A portion of the gltA and ompA gene data subjected to phylogenetic analysis revealed that the detected SFGR clustered into two species, Rickettsia raoultii and the new Rickettsia species Candidatus Rickettsia jingxinensis. Detection of both Rickettsia spp. in this region indicates a potential public health threat posed by SFGR infection in Yunnan Province.

Prevalence of plasmodium, leptospira and rickettsia species in Northern Tanzania: a community based survey

BACKGROUND

The overlap of symptoms, geographic and seasonal co-occurrence of Plasmodium, Leptospira and Rickettsia infections makes malaria diagnosis difficult, increasing the chances of misdiagnosis. The paucity of data on the prevalence Plasmodium, Leptospira and Rickettsia infections contributes to an overly diagnosis of malaria. We aimed to determine the prevalence and distribution of Plasmodium, Leptospira and Rickettsia infections in northern Tanzania.

METHODS

A community based, cross sectional survey was conducted in two sites in Northern Tanzania. PCR was used to detect Plasmodium, Leptospira and Rickettsia infections.

RESULTS

The prevalence of P. falciparum and Leptospira spp were 31/128 (24.2%) and 3/128 (2.3%), respectively. No Rickettsia infection was detected in any of the two sites. Taking study sites separately, Plasmodium infection was detected in 31/63(49.2%) of participants in Bondo while Leptospira infection was detected in 3/65(4.6%) of participants in Magugu. Plasmodium was not detected in Magugu while no Leptospira infections were detected in Bondo. Fever was significantly associated with Plasmodium infection (χ2= 12.44, p<0.001) and age (χ2=17.44, p=0.000).

CONCLUSION

Results from this study indicate Plasmodium infection as the main cause of fever in the studied sites. While Plasmodium and Leptospira contribute to fevers, Rickettsia infection is an insignificant cause of fever in Northern Tanzania.

Candidatus Rickettsia senegalensis in Cat Fleas (Siphonaptera: Pulicidae) Collected from Dogs and Cats in Cauca, Colombia

Rickettsia typhi and Rickettsia felis (Rickettsiales: Rickettsiaceae) are flea-transmitted pathogens. They are important causes of acute febrile illness throughout the world. We, therefore, sought to identify the rickettsial species present in the fleas of dogs and cats in the department of Cauca, Colombia. In this study, we collected 1,242 fleas from 132 dogs and 43 fleas from 11 cats. All fleas were morphologically identified as Ctenocephalides felis (Bouché) adults and organized in pools for DNA extraction (234 pools from dogs and 11 from cats). The gltA gene from rickettsiae was targeted for screening amplification using conventional PCR. In total, 144 of the 245 pools (58.7%) were positive. The positive samples were then processed for the amplification of the 17kDa antigen gene (144/144; 100% positive) and sca5 gene (140/144; 97.2% positive). In addition, restriction enzyme length polymorphism analysis using NlaIV on the amplified product of the sca5 gene demonstrated several organisms: 21/140 (15%) were R. felis, 118/140 (84.3%) were Rickettsia asemboensis, and 1/140 (0.7%) were Candidatus Rickettsia senegalensis. Subsequent sequencing confirmed Candidatus Rickettsia senegalensis in C. felis collected from dogs the first reported from Colombia.

Fleas of Shrews and Rodents in Rural Lowland Taiwan

Fleas transmit a variety of pathogens to humans but are relatively understudied in comparison to mosquitoes and ticks, including in Taiwan, where fleas in rural lowlands have never been systematically surveyed. In total, 700 fleas of four species were collected from 1,260 shrews and rodents at nine counties across lowland Taiwan. Nosopsyllus nicanus Jordan (Siphonaptera: Ceratophyllidae) and Xenopsylla cheopis Rothschild (Siphonaptera: Pulicidae) were the most abundant flea species (79.0 and 14.6% of total fleas, respectively); the former was largely limited to the islets, while the latter was restricted to the Taiwan main island. Rattus losea Swinhoe (Rodentia: Muridae) was the most common small mammal species (49.3% of total) and hosted the majority of fleas (88.3% of total). Five Rickettsia spp., including Rickettsia conorii Brumpt (Rickettsiales: Rickettsiaceae), Rickettsia felis Bouyer et al. Rickettsia japonica Uchida, Rickettsia raoultii Mediannikov, and Rickettsia rickettsii Brumpt or closely related species, were identified from 67 individually assayed fleas based on ompB and gltA genes. Rickettsia felis, mainly transmitted by fleas, was detected in one X. cheopis in southern Taiwan where a confirmed human case of infection with R. felis has been reported. The presence of R. felis, along with the other four tick-borne Rickettsia spp., demonstrates that a variety of rickettsiae circulate in rural lowland Taiwan and could pose risks to human health.

Molecular Detection of Spotted Fever Group Rickettsiae (Rickettsiales: Rickettsiaceae) in Dermacentor variabilis (Acari: Ixodidae) Collected Along the Platte River in South Central Nebraska

Dermacentor variabilis is the predominant tick species in Nebraska and is presumed to be the primary vector of Rickettsia rickettsii associated with cases of Rocky Mountain spotted fever (RMSF). Interestingly, RMSF cases in Nebraska have increased on a year-to-year basis, yet the prevalence of R. rickettsii in D. variabilis ticks has not been established for Nebraska. Here we sought to set a baseline for the prevalence of R. rickettsii and other spotted fever group (SFG) rickettsiae harbored by D. variabilis ticks. Over a 3-yr period, D. variabilis were collected along the Platte River in south central Nebraska. Individual tick DNA was analyzed using endpoint PCR to identify ticks carrying SFG rickettsiae. In total, 927 D. variabilis were analyzed by PCR and 38 (4.1%) ticks tested positive for SFG rickettsiae. Presumptive positives were sequenced to identify the Rickettsia species, of which 29 (76%) were R. montanensis, 5 (13%) were R. amblyommatis, 4 (11%) were R. bellii, and R. rickettsii was not detected. These data indicate that R. rickettsii is likely at a low prevalence in south central Nebraska and spillover of R. amblyommatis into D. variabilis is likely occurring due to the invasive lone star tick (Amblyomma americanum). In addition, our data suggest that R. montanensis and R. amblyommatis could be associated with the increase in SFG rickettsiae infections in Nebraska. This information will be of value to clinicians and the general public for evaluating diagnosis of disease- and risk-associated environmental exposure, respectively.

Documentation of the Expansion of the Gulf Coast Tick (Amblyomma maculatum) and Rickettsia parkeri: First Report in Illinois

The Gulf Coast tick, Amblyomma maculatum, is of public and veterinary health concern, as it is the primary vector of Rickettsia parkeri and Hepatozoon americanum, causative agents of Rickettsiosis and American canine hepatozoonosis. The Gulf Coast tick's range has expanded over the last 50 yr into the mid-Atlantic states, and its expansion is expected to continue northward. We are reporting the presence of A. maculatum for the first time in Illinois, including a total of 18 specimens collected at 6 different sites during surveys in 2013 and 2019. Fourteen of these specimens were screened for Rickettsia parkeri, which resulted in the detection of this bacteria in 8 samples from 4 counties. By depositing these specimens in scientific collections, we provide materialistic evidence of their establishment in 2 counties. We urge health officials to rely on and use scientific collections to document the expansion of these and other vectors across the country. Additionally, we recommend that health practitioners become aware of the clinical similarities between Rocky Mountain Spotted Fever (caused by Rickettsia rickettsii) and "tidewater" fever (caused by R. parkeri).

Rickettsia japonica Infections in Humans, Xinyang, China, 2014-2017

During 2014–2017, we screened for Rickettsia japonica infection in Xinyang, China, and identified 20 cases. The major clinical manifestations of monoinfection were fever, asthenia, myalgia, rash, and anorexia; laboratory findings included thrombocytopenia and elevated hepatic aminotransferase concentrations. Physicians in China should consider R. japonica infection in at-risk patients.

Rickettsia mongolitimonae Encephalitis, Southern France, 2018

We report a case of Rickettsia sibirica mongolitimonae infection, an emerging tickborne rickettsiosis, with associated encephalitis in a 66-year-old man. Diagnosis was rapidly confirmed by quantitative PCR obtained from an eschar swab sample. The patient was successfully treated with oral doxycycline.

ARGAS (PERSICARGAS) GIGANTEUS SOFT TICK INFECTION WITH RICKETTSIA HOOGSTRAALI AND RELAPSING FEVER BORRELIA ON WILD AVIAN SPECIES OF THE DESERT SOUTHWEST, USA

Changing climatic conditions and the northward expansion of ticks and pathogens are of immense importance to human, animal, and environmental health assessment and risk management. From 2014 through 2015, a wildlife rehabilitation center in south-central Arizona, US noted soft ticks (Argasidae) infesting 23 birds, including Cooper's Hawks (Accipiter cooperii), Gray Hawks (Buteo plagiatus), Harris's Hawks (Parabuteo unicinctus), Red-tailed Hawks (Buteo jamaicensis), Great Horned Owls (Bubo virginianus), Common Ravens (Corvus corax), and a Greater Roadrunner (Geococcyx californianus), during the late summer seasonal rainy seasons. The parasites numbered in the hundreds on individual birds. Infested birds were moribund, obtunded, or paralyzed on presentation, with no prior histories of illness or evidence of trauma. Tick and avian blood samples were collected for vector-borne pathogen analysis focusing on the molecular detection of Rickettsia and Borrelia species. Ticks were identified as the neotropical species of soft tick, Argas (Persicargas) giganteus; their occurrence in the southern US on raptors represented an expansion of host range. Pathogen testing of ticks showed that 41% of 54 ticks were infected with Rickettsia hoogstraalii and 23% of 26 ticks were infected with a relapsing fever Borrelia; both agents are associated with uncertain health consequences. Among the blood samples, one was infected with the same Borrelia spp.; this Red-tailed Hawk also had Borrelia-positive ticks. With supportive therapy, the majority of birds, 74% (17/23), recovered and were released or permanent residents. The management of soft tick-infested birds and mitigation of future disease risk will require additional characterizations of these poorly studied soft ticks and their associated pathogens.

Rickettsia parkeri and Candidatus Rickettsia andeanae in Tick of the Amblyomma maculatum Group, Mexico

We report Rickettsia parkeri and Candidatus Rickettsia andeanae in ticks of the Amblyomma maculatum group collected from dogs in Sonora, Mexico. Molecular characterization of these bacteria was accomplished by DNA amplification and sequence analysis of portions of the rickettsial genes gltA, htrA, ompA, and ompB.

Rickettsia japonica Infection after Land Leech Bite, Japan

We report a case of Rickettsia japonica infection in an 81-year-old man in central Japan. The patient had fever, rash, and an eschar but no evidence of a tick bite. His symptoms began 8 days after a land leech bite. The land leech is a potential vector of R. japonica.

Distribution and Ecological Drivers of Spotted Fever Group Rickettsia in Asia

Spotted fever group and related rickettsia (SFGR) are a neglected group of pathogens that belong to the genus Rickettsia. SFGR are zoonotic and are transmitted by arthropod vectors, primarily ticks, fleas and mites to accidental hosts. These emerging and re-emerging infections are widely distributed throughout the world. Land-use change and increasing human-wildlife conflict compound the risk of SFGR infection to local people in endemic areas and travelers to these regions. In this article, we discuss the rickettsial organisms causing spotted fever and related diseases, their arthropod vectors in Asia and the impact of land-use change on their spread.

Detection of Rickettsia spp. and Bartonella spp. in Ctenocephalides felis fleas from free-ranging crab-eating foxes (Cerdocyon thous)

Fleas are insects with a worldwide distribution that have been implicated in the transmission of several pathogens. The present study aimed to investigate the presence of Rickettsia spp. (Rickettsiales: Rickettsiaceae) and Bartonella spp. (Rhizobiales: Bartonellaceae) in fleas from free-ranging crab-eating foxes Cerdocyon thous (Linnaeus, 1766) (Carnivora: Canidae) from Rio Grande do Sul, southern Brazil. Fleas were collected manually from animals and used for the molecular detection of Rickettsia spp. and Bartonella spp. Twenty-nine C. thous were sampled in six municipalities. Four foxes were parasitized by 10 fleas, all of which were identified as Ctenocephalides felis (Bouché, 1935) (Siphonaptera: Pulicidae). DNA from Rickettsia felis Bouyer et al., 2001 and Rickettsia asembonensis Maina et al., 2016 were found in three and eight fleas, respectively. In four fleas, DNA of Bartonella sp. was identified. Phylogenetic analysis grouped Bartonella sp. together with other genotypes previously reported in C. felis worldwide. The scenario described in the present study highlights a Neotropical canid parasitized by the invasive cosmopolitan cat flea, which in turn, is carrying potentially invasive vector-borne microorganisms. These findings suggest that C. felis is adapted to wild hosts in wilderness areas in southern Brazil, hypothetically exposing the Neotropical fauna to unknown ecological and health disturbances.

Cross-kingdom analysis of nymphal-stage Ixodes scapularis microbial communities in relation to Borrelia burgdorferi infection and load

The tick microbiota may influence the colonization of Ixodes scapularis by Borrelia burgdorferi, the Lyme disease bacterium. Using conserved and pathogen-specific primers we performed a cross-kingdom analysis of bacterial, fungal, protistan and archaeal communities of I. scapularis nymphs (N = 105) collected from southern Vermont, USA. The bacterial community was dominated by a Rickettsia and several environmental taxa commonly reported in I. scapularis, as well as the human pathogens B. burgdorferi and Anaplasma phagocytophilum, agent of human granulocytic anaplasmosis. With the fungal primer set we detected primarily plant- and litter-associated taxa and >18% of sequences were Malassezia, a fungal genus associated with mammalian skin. Two 18S rRNA gene primer sets, intended to target protistan communities, returned mostly Ixodes DNA as well as the wildlife pathogen Babesia odocoilei (7% of samples), a Gregarines species (14%) and a Spirurida nematode (18%). Data from pathogen-specific and conserved primers were consistent in terms of prevalence and identification. We measured B. burgdorferi presence/absence and load and found that bacterial beta diversity varied based on B. burgdorferi presence/absence. Load was weakly associated with bacterial community composition. We identified taxa associated with B. burgdorferi infection that should be evaluated for their role in vector colonization by pathogens.

Genetic diversity of Haemaphysalis longicornis from China and molecular detection of Rickettsia

The tick Haemaphysalis longicornis (Neumann) (Acari, Ixodidae) is distributed throughout China and is the most notorious blood feeding ectoparasite of livestock. Haemaphysalis longicornis can transmit a large number of pathogens that cause human infectious diseases, such as Rickettsia spp. Here, we characterized the genetic structure of H. longicornis and tested for the presence of Rickettsia spp. from five regions in China. Analysis of the two mitochondrial marker sequences (16S rRNA and COI) and the nuclear sequence (ITS2) showed that the overall level of nucleotide diversity was low and the variability did not differ among the five regions. From the five locations, the infection rates of Rickettsia species ranged from 0 to 65%. The nucleotide diversities of the high-infected group were lower than those of the low- and uninfected group. And in neutrality tests for the high-infected group based on COI sequences, the Tajima's D and Fu's FS were coincidentally < 0 and significant, whereas they were closer to zero and non-significant in low- and uninfected groups.

Prevalence and molecular characterization of Rickettsia spp. in questing ticks from north-western Spain

Tick-borne rickettsioses, most of them belonging to the spotted fever group (SFG), have been recognized as important emerging vector-borne zoonotic diseases. In order to determine the presence of Rickettsia spp. in questing ticks from north-western Spain, 1056 Ixodes ricinus, 19 Dermacentor marginatus, 17 Dermacentor reticulatus and one Ixodes acuminatus were processed. Rickettsia DNA was detected by PCR targeting rOmpA and rOmpB genes. A total of 219 (20.7%) I. ricinus, 19 (100%) D. marginatus and four D. reticulatus (23.5%) were positive. The prevalence was significantly higher in I. ricinus from coastal areas and in winter. Five species were identified: Rickettsia felis, Rickettsia monacensis, Rickettsia raoultii, Rickettsia slovaca and "Candidatus Rickettsia rioja". Our results reveal a significant presence of some pathogenic Rickettsia species in questing tick populations from this area which involves a noticeable risk of rickettsiosis. As R. raoultii, R. slovaca and "Ca. R. rioja" DNA were identified in I. ricinus, considered an unusual vector for these Rickettsia species, further studies are needed to unravel the role of that tick species in the maintenance and transmission of these three Rickettsia species in north-western Spain.

First report of Candidatus Rickettsia mendelii in Ixodes brunneus from the United States

Candidatus Rickettsia mendelii is a novel rickettsial species recently identified in Ixodes ricinus. In this study, Ixodes brunneus collected from wild birds (n = 77 ticks) or vegetation (n = 4 ticks) in southeastern Virginia were surveyed for rickettsial agents. Candidatus Rickettsia mendelii was confirmed in I. brunneus through sequencing of the gltA and 16S rRNA genes. This is the first report of this rickettsial species in Ixodes ticks in North America.

Molecular identification of ticks infesting camels and the detection of their natural infections with Rickettsia and Borrelia in Riyadh province, Saudi Arabia

The present work aimed to identify camel ticks Hyalomma dromedarii and Hyalomma marginatum using direct sequence of the mitochondrial 16S rRNA gene and the detection of their natural infection rate with Rickettsia and Borrelia using the PCR/ hybridization method for amplification of the citrate synthase (gltA) gene. The phylogenetic analysis showed 99% similarity between Hyalomma dromedarii and its reference with accession # L34306.1, as well as between Hyalomma marginatum and its reference with accession # KT391060.1 obtained from GenBank data base. The prevalence of H. dromedarii and H. marginatum was about 99% and 1%, respectively. The intraspecific variation among H. dromedarii ranged between 0.2-6.6%. The interspecific variation between H. dromedarii and H. marginatum was 18.3%. PCR/hybridization of the sampled H. dromedarii detected about 31%, 37% and 18% natural infection with Rickettsia, Borrelia and co-infection with both pathogens, respectively. In contrast, none of Rickettsia or Borrelia was detected in H. marginatum. The present study emphasizes the accuracy of the identification of camel ticks based on molecular techniques. The ability of H. dromedarii to spread more than one disease is an important issue from the epidemiological standpoint. Future epidemiological research should be carried out in Saudi Arabia to monitor the distribution of tick species and suggest effective control strategies.

Microbial diversity in the tick Argas japonicus (Acari: Argasidae) with a focus on Rickettsia pathogens

The soft tick Argas japonicus mainly infests birds and can cause human dermatitis; however, no pathogen has been identified from this tick species in China. In the present study, the microbiota in A. japonicus collected from an epidemic community was explored, and some putative Rickettsia pathogens were further characterized. The results obtained indicated that bacteria in A. japonicus were mainly ascribed to the phyla Proteobacteria, Firmicutes and Actinobacteria. At the genus level, the male A. japonicus harboured more diverse bacteria than the females and nymphs. The bacteria Alcaligenes, Pseudomonas, Rickettsia and Staphylococcus were common in nymphs and adults. The abundance of bacteria belonging to the Rickettsia genus in females and males was 7.27% and 10.42%, respectively. Furthermore, the 16S rRNA gene of Rickettsia was amplified and sequenced, and phylogenetic analysis revealed that 13 sequences were clustered with the spotted fever group rickettsiae (Rickettsia heilongjiangensis and Rickettsia japonica) and three were clustered with Rickettsia limoniae, which suggested that the characterized Rickettsia in A. japonicus were novel putative pathogens and also that the residents were at considerable risk for infection by tick-borne pathogens.

Rickettsioses: Cutaneous findings frequently lead to diagnosis - a review

While epidemic typhus caused by Rickettsia prowazekii posed a significant threat in Europe before and throughout World War II due to its high mortality, the condition fortunately no longer plays a significant role. Nevertheless, rickettsioses, such as African tick bite fever, have been increasingly diagnosed in travelers returning from sub-Saharan Africa. Caused by Rickettsia africae, African tick bite fever presents with characteristic cutaneous findings such as eschar (tache noir) and a rash. Similar findings are also observed in Mediterranean spotted fever caused by Rickettsia conorii. On the other hand, Rocky Mountain spotted fever - caused by Rickettsia rickettsii - is characterized by a rash without an eschar, in combination with distinctly more severe general symptoms. The objective of the present CME article is to familiarize dermatologists with the spectrum of the most common types of rickettsiosis in humans, including their epidemiology, clinical presentation, diagnostic workup, and treatment. Recognition of characteristic cutaneous manifestations and their correct interpretation facilitate early diagnosis. Prompt initiation of treatment usually results in recovery without sequelae.

Cellulitis of the face associated with SENLAT caused by Rickettsia slovaca detected by qPCR on scalp eschar swab sample: An unusual case report and review of literature

BACKGROUND

Tick-borne rickettsioses are infectious diseases caused by obligate intracellular Gram-negative bacteria belonging to the spotted fever groupof Rickettsia.

METHODS

We describe an unusual case of SENLAT (Scalp eschar and neck lymphadenopathy after tick bite), caused byRickettsia slovaca, associated with a cellulitis of the face in a 70-year-old woman, and diagnosed using qPCR on a scalp eschar swab. We review the literature regarding cases of SENLAT-associated-cellulitis and case of SENLAT diagnosed by qPCR on scalp eschar swabs.

RESULTS

We found only one previous report of SENLAT associated with a cellulitis of the face. It was a nine-year-old French girl diagnosed by seroconversion for Rickettsia sp. Our review of the literature showed that qPCR on eschar swab samples is a less invasive method than performing cutaneous biopsy of the eschar and has good sensitivity and specificity (90% and 100%, respectively).

CONCLUSIONS

We report the second case of cellulitis of the face associated with the SENLAT syndrome. Detection of Rickettsia by qPCR on swab sample of the scalp eschar is a simple, noninvasive technique allowing rapid diagnosis and treatment when SENLAT is suspected.

A Cluster of Cases of Rocky Mountain Spotted Fever in an Area Of Colombia Not Known to be Endemic for This Disease

Rocky Mountain spotted fever (RMSF) has been reported in Colombia since 1937. Most recent outbreaks were in 2006-2008, followed by the absence of recognized cases. This report describes new clinical cases of RMSF and epidemiologic investigations. Medical records were reviewed, and fieldwork, serological and molecular diagnostic testing, and bacterial isolation were performed. Fever, hypotension, abdominal discomfort, and rash accompanied by thrombocytopenia and leukopenia were the most characteristic manifestations. Two convalescent sera from the index case and sera from two dogs revealed high anti-spotted fever group Rickettsia antibody titers. Rickettsia rickettsii was isolated from case 4. Cases 2 and 3 were identified by epidemiological connection with the index case. Thus, a new cluster of cases of RMSF was identified in Antioquia, Colombia, with the occurrence of fatal cases, which indicates the active circulation of the bacteria and a potential risk for the population.

Tick-borne pathogens Bartonella spp., Borrelia burgdorferi sensu lato, Coxiella burnetii and Rickettsia spp. may trigger endocarditis

BACKGROUND

Infections caused by tick-borne pathogens such as Bartonella spp., Borrelia burgdorferi s.l., Coxiella burnetii, and Rickettsia spp. are capable of causing serious lesions of the mitral and aortic valves, leading to a need for valve replacement.

OBJECTIVES

The aim of the study was to determine whether such cases are sporadic or frequent. An additional goal was to establish effective diagnostic methods to detect these infections.

MATERIAL AND METHODS

The study involved 148 patients undergoing valve replacement. Blood samples were drawn for serological testing. Samples of the removed mitral and aortic valves were tested with polymerase chain reaction and immunohistochemical staining.

RESULTS

Specific antibodies to Bartonella spp. were detected in 47 patients (31.7%) and in 1 of the healthy controls (1%) (p < 0.05). Antibodies to B. burgdorferi spirochetes were found in 18 of the patients (12.2%) and in 6 blood donors from the control group (5.8%) (p < 0.1). Antibodies to Rickettsia spp. were detected in 12 (8.1%) and to C. burnetii phase I and II antigens in the serum of 1 patient. All the participants in the control group were seronegative to C. burnetii and Rickettsia spp. antigens. Polymerase chain reaction (PCR) tests for detection of Bartonella spp., B. burgdorferi s.l., C. burnetii and Rickettsia spp. DNA in the valve samples were all negative. Inflammation foci with mononuclear lymphoid cells in the aortic and mitral valves were seen in sections stained with hematoxiline and eozine. In sections dyed using the indirect immunofluorescence method with hyperimmune sera, Bartonella spp. and Rickettsia spp. were found.

CONCLUSIONS

The results obtained indicate that laboratory diagnostics for patients with heart disorders should be expanded to include tests detecting tick-borne zoonoses such as bartonelloses, Lyme borreliosis, rickettsioses and Q fever.

A relapsing fever Borrelia and spotted fever Rickettsia in ticks from an Andean valley, central Chile

In humans, emerging infectious diseases are mostly zoonoses with ticks playing an important role as vectors. Tick-borne relapsing fever Borrelia and spotted fever Rickettsia occur in endemic foci along tropical and subtropical regions of the globe. However, both are widely neglected etiologic agents. In this study, we performed molecular analyses in order to assess the presence of Borrelia and Rickettsia DNA in ticks infesting small-mammals within a National Reserve located in the Andes Mountains, central Chile. While hard ticks were negative for the presence of both agents, sequences of four rickettsial (gltA, htrA, ompA, ompB) and two borrelial (16S rRNA and flaB) genes were obtained from larvae of an Ornithodoros sp. morphologically related with Ornithodoros atacamensis. Phylogenetic analyses indicated that the detected Borrelia and Rickettsia spp. belong to the relapsing fever and spotted fever groups, respectively. Moreover, the agents formed monophyletic clades with Rickettsia amblyommatis and "Candidatus Borrelia johnsonii." As positive ticks parasitize rodents within a highly visited National Reserve where outdoor activities are of common practice, the risk for human parasitism should not be discarded.

Serologic and molecular survey of Rickettsia spp. in dogs, horses and ticks from the Atlantic rainforest of the state of Bahia, Brazil

Tick-borne spotted fever in Brazil is known to be caused by two agents, Rickettsia rickettsii and Rickettsia parkeri. Nothing was known about these agents in one area of the Atlantic rainforest biome of Bahia state, where during March to June 2016, 356 rural dogs and 69 horses were sampled and their sera were processed through indirect immunofluorescence assay against antigens of R. rickettsii, R. parkeri, Rickettsia amblyommatis and Rickettsia bellii. Ticks collected from these dogs and horses were molecularly tested for the presence of rickettsial DNA. Overall, 16.4% (58/356) dogs and 24.6% (17/69) horses were seroreactive to Rickettsia spp. Five tick species, Rhipicephalus sanguineus sensu lato (s.l.), Amblyomma ovale, A. sculptum, R. microplus, and A. naponense, were collected from dogs, whereas horses were infested by A. sculptum and Dermacentor nitens. A total of 242 ticks from dogs and 62 from horses were analyzed by PCR targeting rickettsiae, which were detected in only 4/27 (14.8%) A. ovale. Fragments of the rickettsial gltA and ompA genes from these four ticks were 100% identical to the Atlantic rainforest strain of R. parkeri. The presence of A. ovale on dogs was positively associated with local canine seroreactivity to R. parkeri. Our results provide evidence for the transmission of R. parkeri strain Atlantic rainforest from A. ovale to domestic dogs within the rural area of Ilhéus, similarly to other areas of the Atlantic rainforest biome of Brazil, where human cases of R. parkeri-caused spotted fever have been reported.

Molecular identification of spotted fever group Rickettsia in ticks collected from dogs and small ruminants in Greece

Spotted fever group (SFG) Rickettsia are zoonotic and emerging pathogens with considerable impact in public and animal health. Greece is an endemic country of diseases caused by SFG Rickettsia. This work aims to evaluate the prevalence of SFG Rickettsia in ticks collected from domestic hosts including sheep, goats and dogs. Several genetic markers for bacterial genes, such as 16S rRNA, ompA, ompB, atpA, gltA, recA, dnaA and dnaK, were amplified and sequenced to accurately classified the rickettsial pathogens in the ticks. Taxonomy and species classification of the Rickettsia was achieved by combining phylogenetic and in silico digestion analysis of the gene sequences obtained. A total of 187 ticks were collected and classified at the species level as Ixodes gibosus, Dermacentor marginatus, Haemaphysalis parva, H. sulcata, H. punctata, Hyalomma scavatum, Rhipicephalus sanguineus, R. bursa and Rhipicephalus sp. The results showed that 7.5% of ticks were infected with at least one SFG Rickettsia including R. massiliae (n = 3), R. slovaca (n = 5), R. raoultii (n = 1) and R. hoogstraalii (n = 5), collected from sheep (n = 4), goats (n = 5) and dogs (n = 3). Molecular analysis revealed the presence of novel genetic variants of R. hoogstraalii (in H. sulcata and H. parva from goat and sheep) and R. raoultii (in D. marginatus from goat). These results proof the presence of SFG Rickettsia in domestic hosts in Greece, and support the need for continued monitoring, surveillance and further analyses of other hosts and study areas.

Molecular detection of Rickettsia rickettsii in ticks associated with the bobcat (Lynx rufus) in northeast Mexico

The study of rickettsial agents associated with ticks from wild felines is scarce. In Europe, three species of Rickettsia have been detected (Rickettsia helvetica, Rickettsia massiliae, and Rickettsia monacensis) in ticks collected from the Iberian lynx (Lynx pardinus). However, no studies have been conducted on another lynx species. For this reason, the aim of this study was to identify the diversity of Rickettsia species in ticks associated with bobcats (Lynx rufus) collected in the State of Tamaulipas, Mexico. During 1999 and 2004, nine bobcats from two municipalities of the state were trapped and visually inspected for the presence of ticks. A total of 95 ticks were collected from these lynxes. Ticks were preserved in 96% ethanol. Subsequently we identified the presence of Rickettsia DNA by the amplification of several fragments of genes 17 kDa, ompA and ompB. Recovered sequences were concatenated, aligned, and compared with those of reference deposited in GenBank. Additionally, a phylogenetic analysis was performed using the Maximum Likelihood method. The ticks were morphologically identified as belonging to the species Dermacentor variabilis. We selected a subset of 60 ticks which were examined, and 5% (3/60) were positive with an identity of 99% to sequences of R. rickettsii deposited in GenBank. The results obtained represent the first record of R. rickettsii in ticks associated with wild carnivores, and in particular with bobcats distributed in northeast of Mexico.

Genetic diversity, population structure and rickettsias in Amblyomma ovale in areas of epidemiological interest for spotted fever in Brazil

Amblyomma ovale (Ixodida: Ixodidae) Koch, 1844 is widely-reported in the neotropical region and is the main vector in the epidemic cycle of Rickettsia parkeri strain Atlantic rainforest, a bioagent of a milder variety of spotted fever (SF). Because species with wide geographical distributions are known to exhibit variations that influence their vectorial capacity, the present study aimed to analyze genetic diversity and rickettsia infection of A. ovale collected during the investigation and surveillance of SF cases in the Cerrado and Atlantic rainforest (ARF) Brazilian biomes. Samples had their DNA extracted, amplified and sequenced for 16S rDNA, 12S rDNA, cytochrome oxidase subunit II and D-loop markers for tick analyses, as well as the gltA, htrA, ompA and ompB genes for rickettsia detection. Between 11 and 33 A. ovale haplotypes were identified, all of them exclusive to areas within individual analyzed biome areas. The A. ovale populations appeared to be structured, with Cluster I restricted to Cerrado + ARF isolated in Caatinga and Cluster II to ARF continuous area. Rickettsia bellii, R. parkeri strain Atlantic rainforest (first report for Goiás state, Cerrado), Rickettsia asemboensis (first record in A. ovale for Brazil) and Rickettsia felis (first detection in this ixodid) were identified. A. ovale clusters were not associated with rickettsia types.

Rickettsia species in ticks collected from wild pigs (Sus scrofa) and Philippine deer (Rusa marianna) on Guam, Marianna Islands, USA

The prevalence and diversity of ticks on wildlife species on Guam is understudied, as to date no work has been conducted on the infection of these ticks with Rickettsia (obligate intracellular pathogens that use a variety of ectoparasites as vectors and can cause disease in humans, domestic animals, and wildlife species). The goal of our study was to investigate the presence of Rickettsia species on the island of Guam by testing ticks found on Philippine deer (Rusa marianna) and wild pigs (Sus scrofa). Increasing numbers of these species have led to increased interactions with humans, including hunting, highlighting the importance of studies on vector prevalence and associated zoonotic pathogens. In this study, ticks were removed from Philippine deer and wild pigs in March and April of 2015 and tested for Rickettsia spp. using nested PCR. Overall, a low prevalence of Rickettsia spp. was detected (5.4% (6/112 ticks)). Ticks removed from wild pigs were identified as Amblyomma breviscutatum, one of which was positive for Rickettsia ambylommatis. Ticks recovered from Philippine deer were identified as Rhipicephalus microplus, and five were positive for Rickettsia; two with R. amblyommatis and one with 'Candidatus Rickettsia senegalensis', a recently proposed species in the R. felis cluster. The remaining two sequences were short and species classification was not possible. Rickettsia felis is a known zoonotic pathogen in the spotted fever group of Rickettsia and there is evidence that 'C. R. senegalensis' can also cause illness in people. This study confirms the occurrence of Rickettsia in ticks on Guam and highlights the presence of potential human pathogenic species in the R. felis cluster.

The role of juvenile Dermacentor reticulatus ticks as vectors of microorganisms and the problem of 'meal contamination'

Juvenile Dermacentor reticulatus ticks inhabit nests and burrows of their rodent hosts and cannot be collected from vegetation. To detect vertical transmission of Babesia canis in D. reticulatus, we studied larvae and nymphs collected from rodents. However, the molecular techniques used for detection of pathogen DNA are sensitive enough to detect not only pathogens vectored by ticks but also those taken up with current or previous blood meals ('meal contamination') or just present in the environment and on the tick or host surface ('environmental contaminations'). Thus, an additional aim of our study was to evaluate the extent of such contamination while studying feeding ticks collected from rodents. Juvenile D. reticulatus were collected from 140 rodents: 91 bank voles trapped in two forest sites in the Mazury Lake District and 49 rodents (Apodemus and Microtus spp.) from an open habitat near the town of Białobrzegi in Central Poland. Altogether 504 D. reticulatus ticks, comprising 266 individually evaluated nymphs and 238 larvae assigned to 50 larval pools, were studied for the presence of Babesia, Bartonella and Rickettsia spp. DNA. Statistical analyses were conducted to (1) evaluate the effect of rodent host factors (species, sex and age) on prevalence of infection in ticks, and (2) to compare the frequency of positive samples between groups of pathogen-positive and pathogen-negative rodent hosts. To complete the last aim, blood samples obtained from 49 rodents from Białobrzegi were studied for the presence of Babesia and Bartonella DNA. Infestation of rodent hosts with juvenile ticks ranged between 46 and 78%, with a mean abundance of 3.6 ticks/rodent for D. reticulatus and 4.8 ticks/rodent for Ixodes ricinus. The highest prevalence of PCR-positive D. reticulatus samples was obtained for Rickettsia spp. (28%) and R. raoultii was identified in 22 sequenced PCR products. Babesia DNA was detected in 20 (7.5%), including B. microti in 18 (6.8%) and B. canis in two (0.8%) of 266 D. reticulatus nymphs that were analyzed. Babesia microti DNA was also detected in four pools of D. reticulatus larvae (4/50 pools = 8%). The detection success of B. microti in D. reticulatus was associated with the species of the rodent hosts of the ticks (much higher for typical B. microti-host-species such as Microtus spp. than for Apodemus spp.) and host age (3 × higher in ticks collected from adult hosts in comparison to juvenile ones). Moreover, the DNA of B. microti was detected in 68% of D. reticulatus nymphs collected from B. microti-positive rodents in comparison to only 1.6% of nymphs collected from B. microti-negative rodents. Bartonella DNA was detected in 18% of D. reticulatus tick samples (38% of larval pools, 14% of nymphs). Again, host factors played important roles for 'tick positivity'-the highest prevalence of positive ticks was on Apodemus spp., which are regarded as Bartonella reservoirs. Bartonella DNA was detected in 42% of nymphs and 57% of larval pools collected from Bartonella-positive rodents in comparison to 28% of nymphs and 11% of larvae collected from Bartonella-negative rodents. Vertical transmission of B. canis in D. reticulatus ticks was confirmed in the field. Additionally, we demonstrated that 'meal contamination' generates a confounding signal in molecular detection of pathogen DNA extracted from ticks collected from infected hosts and must be taken into account in evaluating the competence of tick species as vectors.

Rickettsia japonica Infections in Humans, Zhejiang Province, China, 2015

We investigated 16 Japanese spotted fever cases that occurred in southeastern China during September–October 2015. Patients had fever, rash, eschar, and lymphadenopathy. We confirmed 9 diagnoses and obtained 2 isolates with high identity to Rickettsiajaponica strain YH. R. japonica infection should be considered for febrile patients in China.

Japanese Spotted Fever in Eastern China, 2013

We isolated Rickettsia japonica from a febrile patient in Lu'an City, China, in 2013. Subsequently, we found an R. japonica seroprevalence of 54.8% (494/902) in the rural population of Anhui Province and an R. japonica prevalence in Haemaphysalis longicornis ticks of 0.5% (5/935). R. japonica and its tick vector exist in China.

Spotted Fever Group Rickettsiae in Inner Mongolia, China, 2015-2016

We found Rickettsia raoultii infection in 6/261 brucellosis-negative patients with fever of unknown origin in brucellosis-endemic Inner Mongolia, China. We further identified Hyalomma asiaticum ticks associated with R. raoultii, H. marginatum ticks associated with R. aeschlimannii, and Dermacentor nuttalli ticks associated with both rickettsiae species in the autonomous region.

Ticks and serosurvey of anti-Rickettsia spp. antibodies in wild boars (Sus scrofa), hunting dogs and hunters of Brazil

Background

Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters.

Methods

Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii, Rickettsia parkeri, Rickettsia bellii, Rickettsia rhipicephali and Rickettsia amblyommatis. Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A. sculptum, A. brasiliense and A. aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp.

Results

A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum, 910/1,584 (57.4%) as Amblyomma brasiliense, 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum. All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A. sculptum. No tested tick was positive by standard PCR to SFG Rickettsia spp.

Conclusions

The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.

The present study reported serological findings and molecular assays of Rickettsia spp and ticks of wild boars, simultaneous to their correspondent hunting dogs and hunters. Seropositivity for Rickettsia spp. was higher in wild boars when compared to dogs and humans but was similar between dogs and humans. Despite Rickettsia spp. prevalence was statistically higher in southern than central-western Brazil for wild boars, no significance was observed in hunting dogs and hunters. For the first time, A. sculptum ticks were founded in wild boars from the subtropical climate of southern Brazil. Despite human beings have been considered less exposed to ticks (and therefore rickettsiae) than animals, specific human activities such as wild boar hunting may increase the risk of exposure and consequently tick-borne disease. Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. These results may provide important findings for public action planning to prevent neglected vector-borne diseases in overlapping areas of wild boars, hunting dogs and hunters. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.

Endoparasites and vector-borne pathogens in dogs from Greek islands: Pathogen distribution and zoonotic implications

The present study investigated the presence of endo- and ecto-parasites, and vector-borne pathogens, in dogs from four islands of Greece. A total of 200 (123 owned and 77 sheltered) dogs were examined with different microscopic, serological and molecular methods.

Of the examined dogs, 130 (65%) were positive for one or more parasites and/or vector-borne pathogens. The most common zoonotic intestinal helminths recorded were Ancylostomatidae (12.5%) and Toxocara canis (3.5%). Ninety-three dogs (46.5%) seroreacted to Rickettsia conorii. Twenty-two (11%) of them were also PCR positive and 7 (3.5%) showed corpuscles suggestive of Rickettsia spp. on the blood smears. Nineteen dogs (9.5%) were seropositive for Ehrlichia canis, three of them being also PCR positive. Dogs positive for Anaplasma phagocytophilum-Anaplasma platys (1%), Dirofilaria immitis (0.5%) and Babesia canis (0.5%) were also found. Fleas and ticks were recorded in 53 (26.5%) and 50 (25%) dogs, respectively, and all specimens were identified as Ctenocephalides felis felis and Rhipicephalus sanguineus sensu lato. Binary multiple univariate Generalized Linear Models were used to investigate factors and clinical signs related to the recorded positivity, while the association of specific signs with the pathogens was evaluated using tests of independence. Knowledge of occurrence and impact of zoonotic parasites and vector-borne pathogens in dog populations is crucial to prevent the infection in animals and people, and to control the risk of spreading of these pathogens in endemic and non-endemic areas.

Both owned and sheltered dogs can harbor a variety of intestinal and extra-intestinal endoparasites, as well as vector-borne pathogens and ectoparasites, of zoonotic concern. Dog shelters and stray dogs are present in several touristic areas of Greece, including Sporades and Cyclades islands, where tourists often bring their pets with them, likely travelling from non-endemic to endemic areas. The present study has been carried out with the aim to evaluate the occurrence of the aforementioned pathogens. Data obtained showed that they are present in canine populations of Greece, with possibilities of infection for travelling dogs, which can also contribute to the spreading of zoonotic vector-borne diseases, introducing new pathogens in previously non-endemic areas. For these reasons, a constant monitoring of the epidemiological situation, improving control measures and correct diagnostic approaches are of primary importance for the prevention of canine and human infections, decreasing the spreading of potentially deadly pathogens.

Distinguishing Japanese Spotted Fever and Scrub Typhus, Central Japan, 2004- 2015

Japanese spotted fever (JSF) and scrub typhus (ST) are endemic to Japan and share similar clinical features. To document the clinical and epidemiologic characteristics that distinguish these 2 rickettsial diseases, during 2004-2015 we recruited 31 JSF patients, 188 ST patients, and 97 nonrickettsial disease patients from the southern Boso Peninsula of Japan. JSF occurred during April-October and ST during November-December. Patients with JSF and ST were significantly older and more likely to reside in wooded areas than were patients with nonrickettsial diseases. Spatial analyses revealed that JSF and ST clusters rarely overlapped. Clinical findings more frequently observed in JSF than in ST patients were purpura, palmar/plantar rash, hyponatremia, organ damage, and delayed defervescence after treatment. Although their clinical features are similar, JSF and ST differ in seasonality, geographic distribution, physical signs, and severity. Because a considerable percentage of patients did not notice rash and eschar, many rickettsial diseases might be underdiagnosed in Japan.

Rickettsia species in ticks that parasitize amphibians and reptiles: Novel report from Mexico and review of the worldwide record

Ticks are obligate haematophagous ectoparasites that are associated with a wide range of vertebrate hosts, among them also reptiles and amphibians. They have dynamic ecological interactions with multiple microorganisms, ranging from endosymbionts to pathogens, such as the members of the genus Rickettsia. The aim of this work was to detect Rickettsia in ticks from amphibians and reptiles from southern Mexico by the amplification, sequencing and phylogenetic reconstruction of the gltA and ompA genes, and also to compile all the published records worldwide of Rickettsia associated with ticks attached to reptiles and amphibians, in order to elucidate the host-parasite relationships, and to identify the geographical distribution of each bacterial species. We record for the first time the presence of Rickettsia sp. strain Colombianensi and Rickettsia amblyommatis in ticks from several reptiles and amphibians collected in three new localities from the states of Guerrero and Veracruz, Mexico. Additionally, we here report 23 Rickettsia taxa associated with 18 tick species attached to 42 host taxa of amphibians and reptiles in 36 countries. Our findings increase the inventory of rickettsia reported in Mexico and summarizes the knowledge of these bacteria associated with ticks of this particular group of vertebrate host worldwide.

Rickettsia parkeri in Dermacentor parumapertus Ticks, Mexico

During a study to identify zoonotic pathogens in northwestern Mexico, we detected the presence of a rickettsial agent in Dermacentor parumapertus ticks from black-tailed jackrabbits (Lepus californicus). Comparison of 4 gene sequences (gltA, htrA, ompA, and ompB) of this agent showed 99%–100% identity with sequences of Rickettsia parkeri.

Bartonella and Rickettsia Infections in Haematophagous Spinturnix myoti Mites (Acari: Mesostigmata) and their Bat Host, Myotis myotis (Yangochiroptera: Vespertilionidae), from Poland

Hematophagous Spinturnix myoti mites and their host, the greater mouse-eared bat (Myotis myotis), were tested for the presence of Bartonella spp., Rickettsia spp., and Anaplasma phagocytophilum. In total, Bartonella spp. DNA was amplified in 28% of 134 mite pools and in 25% of 59 bats tested by PCR targeting a fragment of citrate synthase gltA gen. Adult mites were at least threefold more frequently infected compared to immature stages. The overall infection prevalence among mite pools from cave-dwelling bats was higher than for those collected from attic shelters. Three distinct genotypes were detected. The most prevalent genotype in mites and bats matched closely with Candidatus Bartonella hemsundetiensis identified in bats from Finland and was relatively distant from bat-borne Bartonella strains described in the UK and France. Importantly, most sequences were close to those reported in forest workers from Poland. The presence of identical genotype among S. myoti samples and M. myotis bats suggests that bartonellae can be shared between mites and their bat hosts. In this case, wing mites could serve as vectors, whereas their hosts as reservoirs. One blood sample was positive by PCR for the msp2 gene of A. phagocytophilum. Two mite pools yielded Rickettsia spp. DNA. Both sequences were distinct from any known species but can be classified as spotted fever group Rickettsia spp. Our findings expanded our knowledge on the role of spinturnicid mites in the ecology and epidemiology of bacterial infections associated with vespertilionid bats, especially regarding the genus Bartonella.

Long-term trends of tick-borne pathogens in regard to small mammal and tick populations from Saxony, Germany

BACKGROUND

Rodents are important in the life-cycle of ticks as hosts for immature developmental stages. Both rodents and ticks are of public health interest as they are reservoirs and vectors for different tick-borne pathogens (TBP). The aim of this study was to reassess the prevalence of TBP in previously studied areas of the city of Leipzig (Saxony, Germany).

METHODS

In the years 2015-2017 rodents and ticks were collected in parks and forest areas in Saxony. DNA was extracted from the rodents, attached and questing ticks. Samples were screened for the presence of Anaplasma phagocytophilum, Babesia spp., Borrelia burgdorferi (s.l.), "Candidatus Neoehrlichia mikurensis" (CNM), Bartonella spp., Hepatozoon spp. and Rickettsia spp. using PCR methods. Rodent, attached nymph and questing tick (nymph and adult) samples were tested individually, while attached larvae were further processed in pools.

RESULTS

A total of 165 rodents (Apodemus agrarius, n = 1; A. flavicollis, n = 59; Arvicola terrestris, n = 1; Myodes glareolus, n = 104), 1256 attached ticks (Ixodes ricinus, n = 1164; Dermacentor reticulatus, n = 92) and 577 questing ticks (I. ricinus, n = 547; D. reticulatus, n = 30) were collected. The prevalence levels in rodents were 78.2% for Bartonella spp., 58.2% for CNM, 49.1% for B. burgdorferi (s.l.) 29.1% for Rickettsia spp. and 24.2% for Hepatozoon spp. The minimal infection rates (MIR) in attached larvae ticks were 39.8% for Rickettsia spp., 32.7% for Bartonella spp., 7.1% for CNM and 8.8% for B. burgdorferi (s.l.) and the prevalence rates in attached nymphs were 33.7% for Bartonella spp., 52.9% for Rickettsia spp., 13.5% for CNM and 11.3% for B. burgdorferi (s.l.) Both rodents and attached ticks were negative for Babesia spp. The prevalence in questing ticks was 18.2% for Rickettsia spp., 7.3% for CNM, 6.4% for B. burgdorferi (s.l.) and 1.4% for Babesia spp. All tested samples were Anaplasma-negative. Sequencing revealed the occurrence of 14 identified species.

CONCLUSIONS

This research is the first evaluation of the prevalence for Hepatozoon spp. in rodents from Germany. In comparison to earlier studies, detected pathogens species remained the same; however, the prevalence for particular pathogens differed.

Fleas from domestic dogs and rodents in Rwanda carry Rickettsia asembonensis and Bartonella tribocorum

Fleas (Siphonaptera) are ubiquitous blood-sucking parasites that transmit a range of vector-borne pathogens. The present study examined rodents (n = 29) and domestic dogs (n = 7) living in the vicinity of the Volcanoes National Park, Rwanda, for fleas, identified flea species from these hosts, and detected Bartonella (Rhizobiales: Bartonellaceae) and Rickettsia (Rickettsiales: Rickettsiaceae) DNA. The most frequently encountered flea on rodents was Xenopsylla brasiliensis (Siphonaptera: Pulicidae). In addition, Ctenophthalmus (Ethioctenophthalmus) calceatus cabirus (Siphonaptera: Hystrichopsyllidae) and Ctenocephalides felis strongylus (Siphonaptera: Pulicidae) were determined using morphology and sequencing of the cytochrome c oxidase subunit I and cytochrome c oxidase subunit II genes (cox1 and cox2, respectively). Bartonella tribocorum DNA was detected in X. brasiliensis and Rickettsia asembonensis DNA (a Rickettsia felis-like organism) was detected in C. felis strongylus. The present work complements studies that clarify the distributions of flea-borne pathogens and potential role of fleas in disease transmission in sub-Saharan Africa. In the context of high-density housing in central sub-Saharan Africa, the detection of B. tribocorum and R. asembonensis highlights the need for surveillance in both rural and urban areas to identify likely reservoirs.

Rickettsia raoultii and Rickettsia sibirica in ticks from the long-tailed ground squirrel near the China-Kazakhstan border

Spotted fever group (SFG) rickettsiae cause infection in humans, domestic animals and wildlife. To date, no rickettsial agents have been reported in hard ticks from the long-tailed ground squirrel (Spermophilus undulatus). A total of 50 adult ticks and 48 nymphs were collected from S. undulatus in the border region of northwestern China. Tick species (identified according to morphological and molecular characteristics) included Dermacentor nuttalli, Dermacentor silvarum and Ixodes kaiseri. Based on the cytochrome c oxidase subunit I (COI) haplotype analysis, I. kaiseri from S. undulatus belongs to an ancestral. In addition, all tick samples were analyzed for the presence of rickettsiae by PCR amplification and sequencing of six genetic markers. Rickettsia raoultii and Rickettsia sibirica subsp. sibirica were shown to occur in adults and nymphs of D. nuttalli and D. silvarum. Rickettsia sibirica subsp. sibirica was also detected in an I. kaiseri adult. Dermacentor silvarum and I. kaiseri were found for the first time on S. undulatus. Rickettsia raoultii and R. sibirica subsp. sibirica were detected in two Dermacentor and one Ixodes species, respectively, suggesting that these rickettsiae circulate in the region of the China-Kazakhstan border by hard ticks infesting S. undulatus.

Molecular detection of Rickettsia spp., Anaplasma platys and Theileria equi in ticks collected from horses in Tayrona National Park, Colombia

Horses are among the domestic animals that closely interact with humans and are highly parasitized by ticks, which are the primary vectors of zoonoses. As horses in Tayrona National Natural Park (PNNT) are used as a means of transporting goods, luggage and people, they are in constant contact with wild animals, workers and tourists from different countries. These factors increase the transmission risk of hemoparasites. The purpose of this study was to determine the presence of Rickettsia sp., Anaplasma sp., and Theileria sp., in horse ticks in this protected area using conventional PCR. We collected 343 ticks of genera Amblyomma, Rhipicephalus and Dermacentor. Of the 61 samples analyzed by PCR, 18 (29.5%) individuals were positive for Rickettsia sp., 15 (24.5%) for Anaplasma sp. and 4 (6.6%) for Theileria sp. This is the first report of these hemoparasite genera in ticks associated with horses in this preserved natural area, demonstrating the importance of additional studies on the presence and epidemiology of hemoparasites and their vectors in domestic and wild animals in conserved areas with a high flow of tourists.

Rickettsia asembonensis Characterization by Multilocus Sequence Typing of Complete Genes, Peru

While studying rickettsial infections in Peru, we detected Rickettsia asembonensis in fleas from domestic animals. We characterized 5 complete genomic regions (17kDa, gltA, ompA, ompB, and sca4) and conducted multilocus sequence typing and phylogenetic analyses. The molecular isolate from Peru is distinct from the original R. asembonensis strain from Kenya.