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Frequency distribution of Anaplasmataceae, Rickettsiaceae and Coxiellaceae pathogens de- tected in African ticks.
Source publication
In Africa, ticks continue to be a major hindrance to the improvement of the livestock industry due to tick-borne pathogens that include Anaplasma, Ehrlichia, Rickettsia and Coxiella species. A systemic review and meta-analysis were conducted here and highlighted the distribution and prevalence of these tick-borne pathogens in African ticks. Relevan...
Contexts in source publication
Context 1
... systematic review and meta-analysis are registered in the international database of prospectively registered systematic reviews (PROSPERO) with the following ID: CRD42022339139. To ensure this review has all the elements and characteristics required for a systematic review, the PRISMA checklist and an additional comprehensive checklist were provided by Migliavaca et al., 2020 [39] (see Table S1). We used the PICO (Population Intervention Comparison Outcome) model to establish the research questions, search strategy and the inclusion/exclusion criteria. ...Context 2
... a consequence, sequencing was not considered a suitable molecular test for estimating the pooled prevalence between studies and was only included in the qualitative analysis. The components of our meta-analytic method are listed in the supplementary checklist [39] in Table S1. Justification for the choice of each component is as follows: ...Context 3
... these premises, we decided to conduct the quantitative (meta-analytical) part of our study only on prevalence data obtained from individual tick samples. A total of 21 species belonging to the family Anaplasmataceae were detected and identified in African ticks, the most represented being E. ruminantium (27 studies), followed by A. marginale (17), A. platys (12), E. canis (11), A. phagocytophilum (10) and A. ovis (9) ( Table 1). A total of 21 species belonging to the family Anaplasmataceae were detected and identified in African ticks, the most represented being E. ruminantium (27 studies), followed by A. marginale (17), A. platys (12), E. canis (11), A. phagocytophilum (10) and A. ovis (9) ( Table 1). ...Context 4
... total of 21 species belonging to the family Anaplasmataceae were detected and identified in African ticks, the most represented being E. ruminantium (27 studies), followed by A. marginale (17), A. platys (12), E. canis (11), A. phagocytophilum (10) and A. ovis (9) ( Table 1). A total of 21 species belonging to the family Anaplasmataceae were detected and identified in African ticks, the most represented being E. ruminantium (27 studies), followed by A. marginale (17), A. platys (12), E. canis (11), A. phagocytophilum (10) and A. ovis (9) ( Table 1). ...Context 5
... total of 25 Rickettsia species were identified in African ticks. The most reported Rickettsia species was R. africae (38 studies), followed by R. aeschlimanni (24 studies), R. massiliae (19 studies) and R. conorii (12 studies) (Table 1). Rickettsia africae was reported in 26 African tick species (Figure 5), mainly Amblyomma variegatum (18 studies), across 17 African countries, i.e., in 71% of the total number of countries where R. africae has been reported ( Figure 6). ...Context 6
... total of 25 Rickettsia species were identified in African ticks. The most reported Rickettsia species was R. africae (38 studies), followed by R. aeschlimanni (24 studies), R. massiliae (19 studies) and R. conorii (12 studies) (Table 1). Rickettsia africae was reported in Regarding the Coxiellaceae family, C. burnetii (20 studies) was far more reported than CLEs and unidentified Coxiella spp. ...Context 7
... africae was reported in Regarding the Coxiellaceae family, C. burnetii (20 studies) was far more reported than CLEs and unidentified Coxiella spp. (four and five studies, respectively; Table 1). Nevertheless, the tick species and number are similar for all the reported Coxiella species ( Figure 5). ...Context 8
... the Coxiellaceae family, C. burnetii (20 studies) was far more reported than CLEs and unidentified Coxiella spp. (four and five studies, respectively; Table 1). Nevertheless, the tick species and number are similar for all the reported Coxiella species ( Figure 5). ...Context 9
... marginale, together with A. centrale, is the agent of bovine anaplasmosis, known to be one of the most economically important diseases of the cattle industry on the African continent, especially in South Africa [57]. Infection of African ticks with A. marginale was reported in more than 15 studies (Table 1), in more than 15 tick species ( Figure 5) from more than 10 African countries (Figure 4), and with a molecular prevalence higher than 10% (QoE = Moderate; Table 7). These numbers indicate that the risk of A. marginale transmission to cattle (the main vertebrate host) from African ticks, especially Rhipicephalus microplus, is quite high. ...Context 10
... Materials: The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/microorganisms11030714/s1, Table S1: PRISMA checklist and additional checklist based on Migliavaca et al., 2020, guidelines ; Table S2: List of papers excluded during full-text examination and relevant exclusion criteria; Table S3: Details of qualitative analysis; Table S4: Details of critical appraisal. References are cited in the supplementary materials. ...Similar publications
Background
Tick-borne pathogen (TBP) surveillance studies often use whole-tick homogenates when inferring tick-pathogen associations. However, localized TBP infections within tick tissues (saliva, hemolymph, salivary glands, and midgut) can inform pathogen transmission mechanisms and are key to disentangling pathogen detection from vector competenc...
Citations
... The pathogen has a worldwide distribution, and the suspected tick vector is R. sanguineus sensu lato ticks (44). The pathogen was detected in 12 African tick species in seven African countries in all regions (45), which may imply that various tick species are involved in its epidemiology. Detection of A. platys in cattle can be attributed to the close association of dogs with cattle in the study areas. ...
... High abundance of A. marginale, the main cause of bovine anaplamsosis, can be attributed to the various tick species involved in transmission (Rhipicephalus, Dermacentor, Ixodes, Hyalomma) and other means of transmission, namely mechanical transmission by contaminated fomites and biting flies and the transplacental route (48,49). A recent study involving African ticks showed that the pathogen was detected in 17 species of the genera Amblyomma, Rhipicephalus and Hyalomma (45). High A. marginale abundance in the study area may increase selection for genetically distinct strains and thus further complicating the efforts towards the development of a safe and effective vaccine. ...
Introduction: Ticks are obligate ectoparasites recognized worldwide as major vectors of several disease-causing pathogens and are good indicators of disease distribution and epidemiology. Recent years have seen a growing concern regarding emerging and re-emerging of economically important tick-borne pathogens of livestock and humans worldwide. The overall objective of the study was to give an insight into current tick distribution and associated bacterial pathogens that may pose a threat to cattle in the sampled study sites.
Methods: A total of 150 cattle were randomly selected from three study sites, Harrismith and Phuthaditjhaba in Free State Province and Bergville in KwaZulu Natal Province, South Africa. Blood samples were collected from the cattle and DNA was subjected to the 16S rRNA gene microbiome sequencing on the circular consensus PacBio sequencing platform. Ticks were also collected from various predilection sites of the sampled animals.
Results: A total of eight tick species were identified and Rhipicephalus evertsi evertsi (79.4%) was the most abundant followed by R. appendiculatus (11.7%), R. afranicus (2.6%), R. simus (2.6%), Hyalomma rufipes (1.2%), R. decoloratus (1.0%), H. truncatum (0.7%) and R. microplus (0.7%). The bacterial microbiome sequence analysis revealed up to 16 phyla and 30 classes in the three study sites. Proteobacteria was the most dominant bacterial phyla with a relative abundance of 67.2% (Bergville), 73.8% (Harrismith) and 84.8% (Phuthaditjhaba), followed by Firmicutes at 9.6% (Phuthaditjhaba), 18.9% (Bergville) and 19.6% (Harrismith).
Conclusion and perspectives: The Chao 1 index estimator revealed significant differences in the α-diversity of microbial communities among three study sites. This study expands the knowledge on tick fauna and microbial communities in the three study sites.
... The pathogen has a worldwide distribution, and the suspected tick vector is R. sanguineus sensu lato ticks (44). The pathogen was detected in 12 African tick species in seven African countries in all regions (45), which may imply that various tick species are involved in its epidemiology. Detection of A. platys in cattle can be attributed to the close association of dogs with cattle in the study areas. ...
... High abundance of A. marginale, the main cause of bovine anaplamsosis, can be attributed to the various tick species involved in transmission (Rhipicephalus, Dermacentor, Ixodes, Hyalomma) and other means of transmission, namely mechanical transmission by contaminated fomites and biting flies and the transplacental route (48,49). A recent study involving African ticks showed that the pathogen was detected in 17 species of the genera Amblyomma, Rhipicephalus and Hyalomma (45). High A. marginale abundance in the study area may increase selection for genetically distinct strains and thus further complicating the efforts towards the development of a safe and effective vaccine. ...
Introduction: Ticks are obligate ectoparasites recognized worldwide as major vectors of several disease-causing pathogens and are good indicators of disease distribution and epidemiology. Recent years have seen a growing concern regarding emerging and re-emerging of economically important tick-borne pathogens of livestock and humans worldwide. The overall objective of the study was to give an insight into current tick distribution and associated bacterial pathogens that may pose a threat to cattle in the sampled study sites.
Methods: A total of 150 cattle were randomly selected from three study sites, Harrismith and Phuthaditjhaba in Free State Province and Bergville in KwaZulu Natal Province, South Africa. Blood samples were collected from the cattle and DNA was subjected to the 16S rRNA gene microbiome sequencing on the circular consensus PacBio sequencing platform. Ticks were also collected from various predilection sites of the sampled animals.
Results: A total of eight tick species were identified and Rhipicephalus evertsi evertsi (79.4%) was the most abundant followed by R. appendiculatus (11.7%), R. afranicus (2.6%), R. simus (2.6%), Hyalomma rufipes (1.2%), R. decoloratus (1.0%), H. truncatum (0.7%) and R. microplus (0.7%). The bacterial microbiome sequence analysis revealed up to 16 phyla and 30 classes in the three study sites. Proteobacteria was the most dominant bacterial phyla with a relative abundance of 67.2% (Bergville), 73.8% (Harrismith) and 84.8% (Phuthaditjhaba), followed by Firmicutes at 9.6% (Phuthaditjhaba), 18.9% (Bergville) and 19.6% (Harrismith).
Conclusion and perspectives: The Chao 1 index estimator revealed significant differences in the α-diversity of microbial communities among three study sites. This study expands the knowledge on tick fauna and microbial communities in the three study sites.
... Transmission of Anaplasma species is intrastadially, transovarially, or transstadially by ticks of various genera such as Rhipicephalus, Ixodes, Amblyomma, Dermacentor and Hyalomma. The pathogens have been detected in over 17 tick species in Africa (Cossu et al., 2023), meaning several of these could be involved in the epidemiology of anaplasmosis. Infection in cattle is mainly by A. marginale, A. centrale, A. bovis, A. phagocytophilum and perhaps Anaplasma sp. ...
... More recently, two reviews related to tick-borne pathogens (including Anaplasma) were conducted. Tawana et al. (2022) reviewed the occurrence of tick-borne pathogens in cattle and ticks in the Southern African Development Community, a regional block that comprises 16 States, and Cossu et al. (2023) and Mucheka et al. (2023) highlighted the distribution and prevalence of various tick-borne pathogens in African ticks. A comprehensive review on bovine anaplasmosis epidemiology in cattle populations in Africa is still lacking. ...
... Pathogens in the genus Anaplasma cause anaplasmosis in various domestic and wild animal species and humans. Various epidemiological studies have assessed the prevalence, distribution and risk factors for Anaplasma infections in individual African countries (Byaruhanga et al., 2018;AL-Hosary et al., 2020;Makgabo et al., 2023;Mwale et al., 2023), while others have reviewed Anaplasma species in African ticks (Cossu et al., 2023;Mucheka et al., 2023) or in domestic ruminants at regional level, such as southern Africa (Tawana et al., 2022) and North Africa (Ben Said et al., 2018). In the present study, we reviewed epidemiological data on Anaplasma species amongst cattle populations from the entire continent. ...
Tick-borne pathogens of the genus Anaplasma cause anaplasmosis in livestock and humans, impacting health and livelihoods, particularly in Africa. A comprehensive review on the epidemiology of Anaplasma species is important to guide further research and for implementation of control approaches. We reviewed observational studies concerning Anaplasma species amongst cattle in Africa. Peer-reviewed studies published in PubMed, Google Scholar, and Web of Science - from database inception to 2022 - were searched. The quality of individual studies was assessed using the Joanna Briggs Institute Critical Appraisal Tool and the pooled prevalences by diagnostic method were estimated using random-effects models. Heterogeneity across the studies was tested and quantified using the Cochran’s Q statistic and the I2 statistic. Potential sources of heterogeneity were investigated by subgroup analysis. A total of 1117 records were retrieved and at the end of the screening, 149 records (155 studies) were eligible for this meta-analysis. The occurrence of Anaplasma species was reported in 31/54 countries in all regions. Seven recognised species (A. marginale, A. centrale, A. phagocytophilum, A. platys, A. capra, A. bovis, A. ovis) and nine uncharacterised genotypes (Anaplasma sp. Hadesa; Anaplasma sp. Saso; Anaplasma sp. Dedessa; Anaplasma sp. Mymensingh; Anaplasma sp. Lambwe-1; Candidatus Anaplasma africae; Anaplasma sp.; Candidatus Anaplasma boleense) were reported in African cattle. Anaplasma marginale was the most frequently reported (n=144/155 studies) and the most prevalent species (serology methods 56.1%, 45.9-66.1; direct detection methods 19.9%, 15.4-24.7), followed by A. centrale (n=26 studies) with a prevalence of 8.0% (95% CI: 4.8-11.9) and A. platys (n=19 studies) with prevalence of 9.7% (95% CI: 5.4-15.2). Anaplasma marginale, A. centrale and A. platys were reported in all Africa’s regions, while A. ovis and A. capra were reported only in the northern and central regions. The uncharacterised Anaplasma taxa were mostly detected in the eastern and southern regions. Subgroup analysis showed that significant determinants for A. marginale exposure (serology) were geographical region (p=0.0219), and longitude (p=0.0336), while the technique employed influenced (p<0.0001) prevalence in direct detection approaches. Temperature was the only significant variable (p=0.0269) for A. centrale. These findings show that various Anaplasma species, including those that are zoonotic, circulate in African cattle. There is need for more genetic and genome data, especially for unrecognised species, to facilitate effective identification, improve livestock and minimise the health risk in human populations. Additional epidemiological data including pathogen occurrence, tick vectors and host range, as well as pathogenicity are essential.
... Anaplasmosis can affect humans and various domestic and wild animal species, including dogs, horses, goats, sheep, cats, ruminants, birds, and other fauna, resulting in the spread of this disease [2,3]. The primary causative agent of anaplasmosis in cattle is Anaplasma marginale, which causes acute anaplasmosis, resulting in severe morbidity with global impact [4]. Bovine anaplasmosis, prevalent in economically disadvantaged regions, inflicts significant financial burdens due to reduced production, weight loss, expensive treatments, and even fatalities and abortions [5]. ...
Background and Aim
Anaplasmosis, a tick-borne disease affecting livestock caused by the bacteria Anaplasma, poses a global concern. This study aimed to estimate the prevalence, spatiotemporal variation, and associated risk factors of anaplasmosis in cattle from the Bannu and Lakki Marwat districts of Khyber Pakhtunkhwa, Pakistan.
Materials and Methods
This study used 197 cattle exhibiting clinical symptoms of anaplasmosis in natural settings. Microscopic examination was used to estimate the prevalence. Potential risk factors, such as sampling regions and months, gender, breed, and age were studied.
Results
The study revealed an overall anaplasmosis prevalence of 19.79%. Bannu district exhibited a higher occurrence at 22.10%, compared to Lakki Marwat district at 17.64%. Young cattle (<2 years) demonstrated a notably higher incidence of anaplasmosis (26.78%) compared to adults (>5 years), which had a prevalence of 12.35% (p < 0.05). Female cattle (22.36%) were more susceptible than male cattle (11.11%). Prevalence peaked in June (45.71%) and was lowest in February (3.57%). Crossbred cattle had a higher prevalence (23.52%) than purebred cattle (11.47%).
Conclusion
Anaplasmosis can be effectively controlled using a comprehensive approach encompassing selective breeding for resilience, targeted care of young calves and females, effective tick control during warmer months, consistent use of insecticides, and proactive risk factor management. Raising awareness among farmers through diverse channels, including media, is pivotal to bolster tick-borne disease management strategies.
... In this study, we detected three species of pathogens, R. africae, E. ewingii, and Candidatus M. mitochondrii, that have been previously detected in spur-thighed tortoise ticks in Morocco (Norte et al. 2021), Qatar (in imported tortoises from pet trade; Barradas et al. 2019Barradas et al. , 2020, Israel (Mumcuoglu et al. 2022), and Italy (Manoj et al. 2021). In Africa, the estimated prevalence of R. africae in Hyalomma ticks is 13.9% (Cossu et al. 2023), and particularly in the North of Morocco, R. africae and Candidatus M. mitochondrii in spur-thighed tortoises have been reported to present a higher prevalence (2.94 and 14.58%, respectively; Norte et al. 2021) than the one encountered by this study. Additionally, although Anaplasma spp., C. burnetii, Babesia spp., CCHFV and H. mauritanica have been documented in other populations of spur-thighed tortoises infested by H. aegyptium throughout their distribution range (Paștiu et al. 2012;Kautman et al. 2016;Akveran et al. 2020;Mumcuoglu et al. 2022;Rjeibi et al. 2022), our study did not yield positive results. ...
... Additionally, although Anaplasma spp., C. burnetii, Babesia spp., CCHFV and H. mauritanica have been documented in other populations of spur-thighed tortoises infested by H. aegyptium throughout their distribution range (Paștiu et al. 2012;Kautman et al. 2016;Akveran et al. 2020;Mumcuoglu et al. 2022;Rjeibi et al. 2022), our study did not yield positive results. Indeed, for example, Africa presents a low estimated prevalence of C. burnetii (Cossu et al. 2023), and in Morocco, of the four pathogens, only H. mauritanica has been detected in spur-thighed tortoises, with a low prevalence of 0-2.1%, being higher in eastern regions (Široký et al. 2009;Norte et al. 2021). The low prevalence of pathogens in ticks might be related to the range and abundance of other potential hosts (wildlife, livestock, or domestic animals), host predation, barriers within tickse.g. ...
Ectoparasites, such as ticks, modulate host population dynamics by impacting demographic traits. They transmit infectious agents among their hosts, posing a critical threat to animal and public health. This study aimed to characterize and analyze the Hyalomma aegyptium infestation on one of its main hosts, the spur-thighed tortoise, its effects on demographic traits, and to determine the diversity of infectious agents present in both ticks and tortoises in the Maamora forest (northwestern Morocco). Our results show that 100% of the tortoises were parasitized by adult ticks in spring, an infestation intensity of 4 ticks/tortoise (5.1 and 3.6 ticks/tortoise in males and females, respectively; 4.2 and 3.3 ticks/tortoise in gravid and non-gravid females, respectively) and an abundance ranging from 1 to 12. Although without significant differences, male tortoises had higher tick abundances than females. The interaction of tortoise sex and body condition was significantly related to tick abundance, male body condition decreased with higher tick abundance in contrast to females. Nevertheless, the interaction of body condition and reproductive stage of females was not significantly related to tick abundance. Gravid females were significantly associated with tick abundance, showing a slightly higher infestation than non-gravid females. Molecular analysis of pooled tick samples revealed the presence of Ehrlichia ewingii, Candidatus Midichloria mitochondrii, and Rickettsia africae, with a minimum infection rate of 0.61 to 1.84%. However, blood sample analysis of the tortoises was infectious agent-free, pinpointing a lack of significant health problems. Given the possible effect on the transmission of zoonotic diseases by spur-thighed tortoises associated with their frequent collection as pets, it should be surveyed to control possible human health problems. In conservation terms, as a long-lived species, the role of tick infestation in demographic traits might be included in the management and conservation programs of spur-thighed tortoises.
... The Anaplasmataceae Anaplasma marginale (A. marginale) is a Rickettsia inherent in the order Rickettsiales [1,2] , which causes Anaplasmosis in cattle from tropical and subtropical areas in several regions of the world [3] . This agent is considered an obligate intraerythrocytic hemoparasite [4] , being responsible for the development of clinical signs such as lethargy, fever, anemia, jaundice, weight loss, decrease in milk production, and abortion [5,6] . ...
