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Simple Summary: Ticks are hematophagous ectoparasites that spread diseases to both animals and humans through their bites. They are notorious for carrying various disease-causing agents, such as viruses, protozoa, and bacteria, which present substantial risks to both human and animal well-being. Continuous changes in the climate can impact both tick distribution and abundance. Understanding of the epidemiology of tick-borne Rickettsia hoogstraalii is limited, with gaps in its molecular detection, genetic characterization, and absence of data, especially from Pakistan. This study aimed to use molecular methods to genetically analyze Rickettsia species, particularly R. hoogstraalii, in Pakistan while also contributing new insights into the pathogen′s global epidemiology. For this purpose, ticks were collected from different hosts, including goats, sheep, and cattle, from six districts of Khyber-Pakhtunkhwa, Pakistan. This study is the first to genetically characterize R. hoogstraalii in Hyalomma anatolicum ticks globally and Haemaphysalis sulcata in Pakistan. This species was first described in 2006 in Croatia and has also been detected in different species of ticks in different countries. The pathogenicity of R. hoogstraalii in vertebrate hosts is not well understood. Encouraging additional research is essential to unveil the involvement of ticks in the transmission and persistence of R. hoogstraalii across various host species. Ticks are hematophagous ectoparasites that transmit pathogens to animals and humans. Updated knowledge regarding the global epidemiology of tick-borne Rickettsia hoogstraalii is dispersed, and its molecular detection and genetic characterization are missing in Pakistan. The current study objectives were to molecularly detect and genetically characterize Rickettsia species, especially R. hoogstraalii, in hard ticks infesting livestock in Pakistan, and to provide updated knowledge regarding their global epidemiology. Ticks were collected from livestock, including goats, sheep, and cattle, in six districts of Khyber Pakhtunkhwa (KP) Pakistan. Overall, 183 hosts were examined, of which 134 (73.2%), including goats (number = 39/54, 72.2%), sheep (23/40, 57.5%), and cattle (71/89, 80%) were infested by 823 ticks. The most prevalent tick species was Rhipicephalus microplus (number = 283, 34.3%), followed by Hyalomma anatolicum (223, 27.0%), Rhipicephalus turanicus (122, 14.8%), Haemaphysalis sulcata (104, 12.6%), Haemaphysalis montgomeryi (66, 8.0%), and Haemaphysalis bispinosa (25, 3.03%). A subset of 210 ticks was selected and screened for Rickettsia spp. using PCR-based amplification and subsequent sequencing of rickettsial gltA and ompB fragments. The overall occurrence rate of R. hoogstraalii was 4.3% (number = 9/210). The DNA of Rickettsia was detected in Hy. anatolicum (3/35, 8.5%) and Ha. sulcata (6/49, 12.2%). However, no rickettsial DNA was detected in Rh. microplus (35), Rh. turanicus (35), Ha. montgomeryi (42), and Ha. bispinosa (14). The gltA and ompB fragments showed 99–100% identity with R. hoogstraalii and clustered phylogenetically with the corresponding species from Pakistan, Italy, Georgia, and China. R. hoogstraalii was genetically characterized for the first time in Pakistan and Hy. anatolicum globally. Further studies should be encouraged to determine the role of ticks in the maintenance and transmission of R. hoogstraalii in different hosts. [ABSTRACT FROM AUTHOR]

Ticks are major vectors of various pathogens of health importance, such as bacteria, viruses and parasites. The problems associated with ticks and vector-borne pathogens are increasing in mountain areas, particularly in connection with global climate change. We collected ticks (n = 2,081) from chamois and mouflon in 4 mountainous areas of France. We identified 6 tick species: Ixodes ricinus, Rhipicephalus bursa, Rh. sanguineus s.l., Haemaphysalis sulcata, H. punctata and Dermacentor marginatus. We observed a strong variation in tick species composition among the study sites, linked in particular to the climate of the sites. We then analysed 791 ticks for DNA of vector-borne pathogens: Babesia/Theileria spp., Borrelia burgdorferi s.l., Anaplasma phagocytophilum, A. marginale, A. ovis, and Rickettsia of the spotted fever group (SFG). Theileria ovis was detected only in Corsica in Rh. bursa. Babesia venatorum (2 sites), Borrelia burgdorferi s.l. (B. afzelii and B. garinii; 2 sites) and Anaplasma phagocytophilum (3 sites) were detected in I. ricinus. Anaplasma ovis was detected at one site in I. ricinus and Rh. sanguineus s.l. SFG Rickettsia were detected at all the study sites: R. monacensis and R. helvetica in I. ricinus at the 3 sites where this tick is present; R. massiliae in Rh. sanguineus s.l. (1 site); and R. hoogstraalii and Candidatus R. barbariae in Rh. bursa in Corsica. These results show that there is a risk of tick-borne diseases for humans and domestic and wild animals frequenting these mountain areas.

Despite high diversity in the Oriental region, ticks of the genus Haemaphysalis have been neglected regarding their genetic data and vector potential. This study aimed to genetically characterize three species of the genus Haemaphysalis: Haemaphysalis cornupunctata, Haemaphysalis kashmirensis, and Haemaphysalis montgomeryi infesting goats and sheep, and Rickettsia spp. associated with these tick species in the Hindu Kush Himalayan range of Pakistan. Altogether, 834 ticks were collected by examining 120 hosts including goats (64/120, 53.3%) and sheep (56/120, 46.6%), in which 86 (71.6%) hosts were found to be tick-infested. The morphologically identified ticks were subjected to DNA extraction and PCR for the amplification of partial 16S rDNA and cox fragments. Rickettsia spp. associated with the collected ticks were detected through the amplification of gltA, ompA and ompB partial fragments. The 16S rDNA of H. cornupunctata and H. montgomeryi showed a maximum identity of 100% with the sequences of the same species, whereas the 16S rDNA of H. kashmirensis showed the highest identity of 93–95% with Haemaphysalis sulcata. The cox sequence of H. montgomeryi displayed 100% identity with the same species. In comparison, the cox sequences of H. cornupunctata and H. kashmirensis showed maximum identities of 87.65–89.22% with Haemaphysalis punctata and 89.34% with H. sulcata, respectively. The gltA sequence of Rickettsia sp. from H. kashmirensis showed the highest identity of 97.89% with Rickettsia conorii subsp. raoultii, while the ompA and ompB fragments from the same DNA samples revealed 100% and 98.16% identity with Rickettsia sp. and "Candidatus Rickettsia longicornii", respectively. Another gltA sequence amplified from H. montgomeryi ticks showed 100% identity with Rickettsia hoogstraalii, while the attempts to amplify ompA and ompB for R. hoogstraalii were unsuccessful. In the phylogenetic tree, the 16S rDNA of H. cornupunctata clustered with the corresponding species while its cox clustered with H. punctata. Both 16S rDNA and cox sequences of H. kashmirensis clustered with H. sulcata. The gltA sequence of Rickettsia sp. was clustered individually in the spotted fever (SF) group of Rickettsia, while the gltA sequence of R. hoogstraalii was clustered with the same species in the transition group of Rickettsia. In the SF group, the rickettsial ompA and ompB sequence clustered with undetermined Rickettsia sp. and "Candidatus Rickettsia longicornii", respectively. This is the earliest study regarding the genetic characterization of H. kashmirensis. This study indicated that ticks belong to the genus Haemaphysalis have the potential of harboring and/or transmitting Rickettsia spp. in the region. [ABSTRACT FROM AUTHOR]

Simple Summary: Ticks are important parasites that feed on the blood of various host species, representing the most important arthropods transmitting diseases in Europe. Continuous changes in both tick distribution and abundance are related to multiple factors, including climate change. These changes have strong implications for both animal and human health; therefore, continuous surveillance of tickborne diseases is required for an appropriate evaluation of the potential risks faced by animals and humans in a given area. The spotted fever group Rickettsia comprises a large number of zoonotic agents with an increasing importance recognized in the last 30 years. The aim of this study was to evaluate these bacteria in ticks in Romania. Five Rickettsia species were identified in different tick species, with new pathogen–tick associations reported. Rickettsia hoogstraalii, one member of this group, was detected for the first time in Romania and in Rhipicephalus rossicus ticks. This species was first described in 2006 in Croatia, and its pathogenicity is not well known. In addition, the detection of R. raoultii and R. monacensis in unfed larvae of Haemaphysalis punctata reinforce the hypothesis of transmission of Rickettsia from female ticks to larvae; therefore the bite of larvae could pose a health risk. Tickborne bacterial pathogens have been described worldwide as risk factors for both animal and human health. Spotted fevers caused by Rickettsiae may cause non-specific symptoms, which make clinical diagnosis difficult. The aim of the current study was to evaluate and review the diversity of SFG Rickettsiae in ticks collected in 41 counties in Romania. A total of 2028 questing and engorged ticks collected in Romania belonging to five species were tested by PCR amplification of Rickettsia spp. gltA and 17-D gene fragments: Ixodes ricinus (n = 1128), Dermacentor marginatus (n = 507), D. reticulatus (n = 165), Rhipicephalus rossicus (n = 128) and Haemaphysalis punctata (n = 100). Five Rickettsia species were identified following DNA sequence analysis: R. helvetica, R. monacensis, R. slovaca, R. raoultii, and R. hoogstraalii. The most common species detected was R. monacensis. Moreover, R. hoogstraalii was detected for the first time in Romania and in R. rossicus ticks. The detection of R. raoultii and R. monacensis in questing larvae of Hae. punctata suggests the possible transovarial transmission of these Rickettsia species in ticks. The detection of R. hoogstraalii for the first time in Romania increases the reported SFG Rickettsia diversity in the country. [ABSTRACT FROM AUTHOR]

Tickborne bacterial pathogens have been described worldwide as risk factors for both animal and human health. Spotted fevers caused by Rickettsiae may cause non-specific symptoms, which make clinical diagnosis difficult. The aim of the current study was to evaluate and review the diversity of SFG Rickettsiae in ticks collected in 41 counties in Romania. A total of 2028 questing and engorged ticks collected in Romania belonging to five species were tested by PCR amplification of Rickettsia spp. gltA and 17-D gene fragments: Ixodes ricinus (n = 1128), Dermacentor marginatus (n = 507), D. reticulatus (n = 165), Rhipicephalus rossicus (n = 128) and Haemaphysalis punctata (n = 100). Five Rickettsia species were identified following DNA sequence analysis: R. helvetica, R. monacensis, R. slovaca, R. raoultii, and R. hoogstraalii. The most common species detected was R. monacensis. Moreover, R. hoogstraalii was detected for the first time in Romania and in R. rossicus ticks. The detection of R. raoultii and R. monacensis in questing larvae of Hae. punctata suggests the possible transovarial transmission of these Rickettsia species in ticks. The detection of R. hoogstraalii for the first time in Romania increases the reported SFG Rickettsia diversity in the country.

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. [ABSTRACT FROM AUTHOR]

The spotted fever group of Rickettsiae is a heterogeneous group of Rickettsiae transmitted by ticks, causing similar diseases in humans (spotted fever). Until recently, it was supposed that a single pathogenic tick-borne SFG Rickettsia circulated in each different geographic area and that R. conorii subsp. conorii was the SFG Rickettsiae circulating in Italy, but in the last decade, thanks to molecular diagnostic, several different Rickettsia species, previously not considered pathogenic for decades, have been isolated from ticks and definitively associated to human disease, also in Italy. The present survey was carried out with the aim of investigating the presence of different SFG Rickettsia species in a geographic area where no information was available. Ticks collected from animals submitted to necropsy, removed from humans in local hospitals and collected from the environment were identified and tested by PCR for Rickettsia spp. based on the gltA gene, and positive PCR products were sequenced. A total of 3286 ticks were collected. Fifteen tick species were recognized, the most represented (79.52%) species in the collection was Ixodes ricinus, followed by Rhipicephalus sanguineus (9.13%). The overall prevalence of Rickettsia infection was 7.58%. Eight species of Rickettsia were identified, the most frequent was R. monacensis (56%), followed by R. helvetica (25.50%). Noteworthy, is the detection in the present study of Rrhipicephali, detected only twice in Italy. These are the first data available on SFG Rickettsiae circulation in the study area and they can be considered as starting point to assess the possible risk for humans.

Tick-borne diseases represent a large proportion of infectious diseases that have become a world health concern. The presence of Rickettsia spp. was evaluated by standard PCR and sequencing in 123 ticks collected from several mammals and vegetation in Sardinia, Italy. This study provides the first evidence of the presence of Rickettsia hoogstralii in Haemaphysalis punctata and Haemaphysalis sulcata ticks from mouflon and Rickettsia helvetica in Ixodes festai ticks from hedgehog. In addition, Rickettsia massiliae , Rickettsia slovaca and Rickettsia aeschlimannii were detected in Rhipicephalus sanguineus , Dermacentor marginatus and Hyalomma marginatum marginatum ticks from foxes, swine, wild boars, and mouflon. The data presented here increase our knowledge of tick-borne diseases in Sardinia and provide a useful contribution toward understanding their epidemiology. [ABSTRACT FROM AUTHOR]

The spotted fever group of Rickettsiae is a heterogeneous group of Rickettsiae transmitted by ticks, causing similar diseases in humans (spotted fever). Until recently, it was supposed that a single pathogenic tick-borne SFG Rickettsia circulated in each different geographic area and that R. conorii subsp. conorii was the SFG Rickettsiae circulating in Italy, but in the last decade, thanks to molecular diagnostic, several different Rickettsia species, previously not considered pathogenic for decades, have been isolated from ticks and definitively associated to human disease, also in Italy. The present survey was carried out with the aim of investigating the presence of different SFG Rickettsia species in a geographic area where no information was available. Ticks collected from animals submitted to necropsy, removed from humans in local hospitals and collected from the environment were identified and tested by PCR for Rickettsia spp. based on the gltA gene, and positive PCR products were sequenced. A total of 3286 ticks were collected. Fifteen tick species were recognized, the most represented (79.52%) species in the collection was Ixodes ricinus, followed by Rhipicephalus sanguineus (9.13%). The overall prevalence of Rickettsia infection was 7.58%. Eight species of Rickettsia were identified, the most frequent was R. monacensis (56%), followed by R. helvetica (25.50%). Noteworthy, is the detection in the present study of Rrhipicephali, detected only twice in Italy. These are the first data available on SFG Rickettsiae circulation in the study area and they can be considered as starting point to assess the possible risk for humans. [ABSTRACT FROM AUTHOR]

The spotted fever group of Rickettsiae is a heterogeneous group of Rickettsiae transmitted by ticks, causing similar diseases in humans (spotted fever). Until recently, it was supposed that a single pathogenic tick-borne SFG Rickettsia circulated in each different geographic area and that R. conorii subsp. conorii was the SFG Rickettsiae circulating in Italy, but in the last decade, thanks to molecular diagnostic, several different Rickettsia species, previously not considered pathogenic for decades, have been isolated from ticks and definitively associated to human disease, also in Italy. The present survey was carried out with the aim of investigating the presence of different SFG Rickettsia species in a geographic area where no information was available. Ticks collected from animals submitted to necropsy, removed from humans in local hospitals and collected from the environment were identified and tested by PCR for Rickettsia spp. based on the gltA gene, and positive PCR products were sequenced. A total of 3286 ticks were collected. Fifteen tick species were recognized, the most represented (79.52%) species in the collection was Ixodes ricinus, followed by Rhipicephalus sanguineus (9.13%). The overall prevalence of Rickettsia infection was 7.58%. Eight species of Rickettsia were identified, the most frequent was R. monacensis (56%), followed by R. helvetica (25.50%). Noteworthy, is the detection in the present study of Rrhipicephali, detected only twice in Italy. These are the first data available on SFG Rickettsiae circulation in the study area and they can be considered as starting point to assess the possible risk for humans.

Ticks (Ixodidae and Argasidae) are important arthropod vectors of various pathogens that cause human and animal infectious diseases. Many previously published studies on tick-borne pathogens focused on those transmitted by ixodid ticks. Although there are increasing reports of viral pathogens associated with argasid ticks, information on bacterial pathogens they transmit is scarce. The aim of this molecular study was to detect and characterize Rickettsia and Anaplasmataceae in three different argasid tick species, Ornithodoros faini, Ornithodoros moubata, and Argas walkerae collected in Zambia. Rickettsia hoogstraalii and Rickettsia lusitaniae were detected in 77 % (77/100) of Ar. walkerae and 10 % (5/50) of O. faini, respectively. All O. moubata pool samples (n = 124) were negative for rickettsial infections. Anaplasmataceae were detected in 63 % (63/100) of Ar. walkerae and in 82.2 % (102/124) of O. moubata pools, but not in O. faini. Phylogenetic analysis based on the concatenated sequences of 16S rRNA and groEL genes revealed that Anaplasma spp. detected in the present study were distinct from previously validated Anaplasma species, indicating that the current knowledge on the diversity and vector range of Anaplasma spp. is incomplete. Our findings highlight new geographical records of R. lusitaniae and R. hoogstraalii and confirm that the wide geographic distribution of these species includes the African continent. The data presented here increase our knowledge on argasid tick-borne bacteria and contribute toward understanding their epidemiology., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

We found a diversity of Rickettsia spp. in seabird ticks from 6 tropical islands. The bacteria showed strong host specificity and sequence similarity with strains in other regions. Seabird ticks may be key reservoirs for pathogenic Rickettsia spp., and bird hosts may have a role in dispersing ticks and tick-associated infectious agents over large distances.