Molecular detection of tick‐borne pathogens in bovine blood and ticks from Khentii,Mongolia

Recent studies reported the detection of DNA from tick‐borne pathogens (TBPs) of veterinary relevance such as Anaplasma marginale, Babesia bigemina, Babesia bovis and Theileria orientalis in bovine blood samples from Mongolia. These findings were unexpected, as the known tick vectors of these pathogens are not known to occur in Mongolia. We therefore conducted a study in May and June 2013 in six districts of Khentii province where DNA of the said TBPs was previously found. Ticks collected from the vegetation and rodents, as well as blood samples from cattle, were screened for the presence of TBPs by reverse line blot (RLB) hybridization. Tick larvae collected from rodents were pooled. A total of 310 adult ticks were collected from the vegetation, and 249 tick larvae were collected from 24 rodents. Adult ticks (n = 2,318) and blood samples were collected from 481 heads of cattle. All adult ticks were identified as Dermacentor nuttalli. DNA from Rickettsia raoultii (252/310; 81.3%), an uncharacterized Anaplasma species preliminary named Anaplasma sp. Mongolia (26/310; 8.4%), Candidatus Midichloria sp. (18/310; 5.8%), Theileria equi (16/310; 5.2%), Babesia caballi (5/310; 1.6%), T. orientalis (1/310; 0.3%), Borrelia afzelii (1/310; 0.3%) and Candidatus Neoehrlichia mikurensis (1/310; 0.3%) was detected in ticks collected from the vegetation. DNA of R. raoultii (27/28; 96.4%) and Midichloria sp. (2/28; 7.1%) was detected in the pooled tick larvae. Anaplasma sp. Mongolia, a species related to Anaplasma ovis based on a multi‐locus analysis, was also detected in 153/481 (31.8%) of the bovine blood samples. DNA of B. bovis, B. bigemina and A. marginale was not detected in the ticks or bovine blood samples from Khentii district.     

Pathogenic Rickettsia in ticks of spur‐thighed tortoise (Testudo graeca) sold in a Qatar live animal market

The dissemination of vector arthropods harbouring zoonotic pathogens through the uncontrolled transboundary trade of exotic and pet animals poses an important threat to Public Health. In the present report, we describe the introduction of pathogenic Rickettsia africae and R. aeschlimanni in ticks removed from imported tortoises in Qatar. A total of 21 ticks were collected from pet spur‐thighed tortoises (Testudo graeca) from Doha, May 2018, and studied for species identification and characterization of Rickettsia spp. Morphological and molecular analysis of ticks allowed their identification as Hyalomma aegyptium. Molecular analysis of partial ompA and gltA genes showed that Rickettsia sequences found on these ticks clustered with sequences classified as R. aeschilimanii and R. africae. Since pre‐adult stages of H. aegyptium also feed on humans, this tick species may play a role in the transmission of R. aeschilimanii and R. africae. We alert for the introduction of non‐native pets as vehicles for tick importation, known vectors for animal and human pathogenic agents. Importation of exotic species into non‐autochthonous countries deserves strict control to enforce robust surveillance and mitigate potential exotic diseases epidemics.     

Survey of ticks of domestic dogs and cattle in three Caribbean islands

Ticks and the pathogens they transmit can cause high morbidity and mortality in domestic animals. As part of a larger study to determine the tick‐borne pathogens infesting domestic animals and wildlife, the aim of this study was to survey the tick species infesting the canine and cattle populations in Trinidad, Tobago and St. Lucia. A total of 1,990 ticks were collected off 179 dogs in Trinidad (n = 163) and Tobago (n = 16) between June 2016 and 2018. Ticks were also collected from cattle throughout Trinidad (n = 1,098), Tobago (n = 306) and St. Lucia (n = 176). Collected ticks were morphologically identified using standard taxonomic keys. Tick‐infested dogs were characterized as pets (n = 161) or hunting dogs (n = 18). Only two tick species, Rhipicephalus sanguineus (1,926; 96.8%) and Amblyomma ovale (64; 3.2%), were found on the dogs. A total of 169 (94.4%) dogs and 10 (5.6%) dogs were infested with R. sanguineus and A. ovale, respectively. Three dogs (1.7%) were infested with both tick species. Hunting dogs or those closely associated with them were infested with A. ovale. Rhipicephalus sanguineus was widely distributed throughout both islands, whereas A. ovale was restricted to small foci in three rural settlements in both Trinidad (n = 2) and Tobago (n = 1). Rhipicephalus (Boophilus) microplus (n = 1,404) was the only tick species found in cattle from Trinidad (n = 62) and Tobago (n = 20), whilst R. B. microplus (n = 171) and Amblyomma variegatum (n = 5) were found infesting 14 and two heads of cattle, respectively, in St. Lucia. These preliminary findings will aid in determining whether there are links between ticks and tick‐borne pathogens associated with domestic, wildlife species and humans and give further insight into the potential movement of ticks and their pathogens between the human, animal and tropical forest interface.     

Molecular epidemiology and phylogeny of spotted fever group Rickettsia in camels (Camelus dromedarius) and their infesting ticks from Tunisia

Rickettsia species are adapted to a wide range of specific animal hosts. Camels (Camelus dromedarius) have been identified as a carrier of various zoonotic pathogens and became a focus of growing public health interest. This study reported the occurrence of rickettsial infection in camels and infesting ticks from five Tunisian governorates. Based on ompB PCR, eight out of 293 camels (2.7%) were found to be infected with Rickettsia spp. Furthermore, 13 tick specimens of Hyalomma impeltatum (10.4%) and 9 of H. dromedarii (8.0%) harboured DNA of Rickettsia bacteria with an overall prevalence rate of 9.2% (22/237). Molecular prevalence of Rickettsia infection varied significantly according to tick infestation for camels and among tick genders. Five rickettsial species, showing a potential public health interest, were revealed by sequencing. Based on ompB partial sequences, five species were identified corresponding to R. aeschlimannii, R. monacensis, R. helvetica and R. massiliae in camels and to R. africae, R. aeschlimannii, R. monacensis and R. helvetica in ticks. Based on ompA typing, three species were revealed corresponding to R. africae and R. monacensis in camels and to R. africae, R. aeschlimannii and R. monacensis in ticks. This is the first report consolidating the hypothesis that camels may serve as potential hosts for Rickettsia spp. and Hyalomma spp. ticks as possible vectors in arid and Saharan areas of Tunisia. The present data highlight the importance of preventive measures and survey that must be implemented in camel herds in order to limit the spread of these vector‐borne bacteria to animals and humans.     

Rickettsia parkeri in free‐ranging wild canids from Brazilian Pampa

Spotted fevers are tick‐borne diseases associated with various Rickettsia species. Rickettsia parkeri sensu stricto (s.s.) is the agent of an emerging eschar‐associated rickettsiosis in humans from the USA and South American Pampa. Considering that R. parkeri s.s. is restricted to Americas and the potential role of dogs in the epidemiology of the disease, it is thus reasonable to hypothesize that wild canids could be involved in the enzootic cycle of this rickettsiosis. The aim of this work was to investigate the potential role of the wild canids from Pampa, Cerdocyon thous (crab‐eating fox) and Lycalopex gymnocercus (Pampas fox), in the ecology of R. parkeri s.s. For that, 32 live‐trapped free‐ranging wild canids were sampled. Ticks were observed in 30 of the 32 foxes. Of the 292 ticks collected, 22 (7.5%) were positive by PCR for the presence of R. parkeri s.s. DNA . Also, 20 (62%) wild canids showed antibodies against R. parkeri . The results suggest that wild canids are involved in the enzootic cycle of R. parkeri s.s. in the Pampa biome and could be responsible for pathogen (and its vectors) dispersal.     

The Emergence of Theileria parva in Jonglei State,South Sudan: Confirmation Using Molecular and Serological Diagnostic Tools

A cross‐sectional survey was carried out in four counties of Jonglei State, South Sudan, between May and June 2012 to determine the distribution and northern limit of Theileria parva, the causative agent of East Coast fever in cattle, and its tick vector Rhipicephalus appendiculatus, as a prerequisite to the deployment of relevant control strategies. A total of 1636 ticks, 386 serum samples and 399 blood samples were collected from indigenous, apparently healthy, cattle of different age groups. Tick species were identified morphologically, and the identity of R. appendiculatus was confirmed by DNA barcoding. Overall, the T. parva infection rate in R. appendiculatus was 25% as shown by nested PCR. ELISA was used to assess antibodies to T. parva, and the overall seroprevalence was 22.8%. PCR of the blood samples showed 55 (13.8%) were positive for T. parva. This is the first molecular confirmation of T. parva DNA in areas north of Juba, where it was previously known and established. The northern limit of T. parva was determined as N⁰06.17.792, about 242 Km north from Juba. Implication of this limit on the epidemiology and control of ECF is discussed.     

A chemical conjugate of the tick P0 peptide is efficacious against Amblyomma mixtum

After Rhipicephalus microplus, the most important tick species affecting livestock industry in Cuba belong to the Amblyomma genus. There are few reports of effective vaccine antigens for these species. Recently, vaccination and challenge trials using a peptide from the P0 acidic ribosomal protein of R. microplus ticks (pP0) as antigen have shown an efficacy around 90% against tick species from the Rhipicephalus genus. Given the high degree of sequence conservation among tick species, pP0 could be an antigen of versatile use in anti‐tick vaccine formulations. In this paper, seven rabbits were immunized with a chemical conjugate of pP0 to keyhole limpet haemocyanin. Rabbits were challenged with an average of 1,900 Amblyomma mixtum larvae from a Cuban tick strain. The average number of recovered fed larvae and the viability of larvae in the moulting process were significantly lower in vaccinated animals compared with the control group. The overall vaccine efficacy of the P0 peptide antigen is 54% according to the calculated parameters.     

Molecular detection of spotted fever group rickettsiae in hard ticks,northern China

Spotted fever group (SFG) rickettsiae are important causative agents of (re)emerging tick‐borne infectious diseases in humans, and ticks play a key role in their maintenance and transmission. In this study, hard ticks were collected from five sampling sites in North China in 2017 and 2018. Of them, Haemaphysalis longicornis, Rhipicephalus microplus and Dermacentor nuttalli were collected from livestock (sheep and goats) and the vegetation, Hyalomma asiaticum from sheep, goats and camels, and Hyalomma marginatum from sheep and goats. The SFG rickettsiae were identified in these ticks by amplifying the partial rrs and complete 17‐kDa genes, with an overall infection rate of 52.9%. In addition, the nearly full‐length rrs and gltA and partial ompA genes were recovered to classify the species of SFG rickettsiae further. Phylogenetic analysis revealed the presence of three human pathogenic species in Hy. asiaticum, Hy. marginatum, Ha. longicornis and De. nuttalli, including two cultured ones (Rickettsia raoultii and Rickettsia aeschlimannii) and one uncultured (Candidatus R. jingxinensis). Furthermore, partial groEL gene was also obtained, and phylogenetic trees were also reconstructed to better understand the genetic relationship with known sequences in each SFG rickettsiae species detected in the current study. Notably, the R. aeschlimannii sequences described in this study were closely related to those from abroad rather than from another part of China, indicating their different origin. However, the R. raoultii and Ca. R. jingxinensis sequences presented close relationship with variants from other parts of China. In sum, our data revealed SFG rickettsiae species in northern China, highlighting the need for surveillance of their infection in local humans.     

First Molecular Identification and Genetic Characterization of Theileria lestoquardi in Sheep of the Maghreb Region

Theileria lestoquardi is the most prominent Theileria species in small ruminants that causes malignant theileriosis of sheep in Africa and Asia. In the present survey, blood samples and ticks were collected in Kebili (southern Tunisia) from 166 Queue Fine de l'Ouest sheep. Giemsa‐stained blood smears, immunofluorescent antibody test (IFAT) and PCR were performed. The DNA was extracted from blood and analysed by PCR targeting 18S rRNA gene of Theileria spp. and then sequenced. A total number of 140 ticks were collected from a total number of 166 sheep during the four seasons. The ticks belonged to two genera and 4 species; the most frequent tick was Hyalomma excavatum 84.3% (118/140) and then Rhipicephalus spp. 15.7% (22/140). Only two animals had positive Giemsa‐stained blood smears, and they were also positive by IFAT. The amplicons had 99.3 and 99.6% homology with the BLAST published T. lestoquardi amplicons. To our knowledge, this is the first report of T. lestoquardi in small ruminants within the Maghreb region.     

Phylogenetic profiling for zoonotic Ehrlichia spp. from ixodid ticks in the Eastern Cape,South Africa

Ticks are obligate hematophagous parasite of vertebrate that transmit a range of pathogenic microorganisms that can cause diseases in livestock and humans. The range of tick‐borne disease causative agents infecting domestic animals and humans has recently increased. Several significant zoonotic tick‐borne diseases such as ehrlichiosis among others are on the increase worldwide. This study was designed to investigate the occurrence of zoonotic Ehrlichia spp. from samples collected from livestock in selected communities in the Eastern Cape Province, South Africa. Tick samples were manually collected from domesticated animals in selected homesteads. The ticks were morphologically identified to species and tested for Ehrlichia infection via polymerase chain reaction (PCR), using genus‐specific disulphide bond formation protein (dsbA) gene primers. This was followed by sequence analysis of amplicons and phylogeny. Of the 1,200 ticks collected, Amblyomma hebraeum was most prevalent (n = 335; 27.9%), followed by Rhipicephalus appendiculatus (n = 274; 22.8%), Rhipicephalus decoloratus; (n = 224; 18.7%) and Rhipicephalus eversti eversti (n = 200, 16.7%). Ehrlichia DNA was detected in 19/1,200 (1.6%) of the screened DNA samples. A homology search of the generated sequences revealed a high percentage of identity between 95% and 98% with other homologous dsbA gene sequences of other Ehrlichia species in GenBank. Phylogenetic analysis showed that the obtained sequences clustered unambiguously with other Ehrlichia sequences from different geographical regions of the world. We concluded that Ehrlichial pathogens are vectored by the ticks collected from domesticated animals in the study areas, thus suggesting concern for public health, as some of the recovered pathogens are zoonotic in nature and could pose serious public health risk through human exposure to tick bites.     

Factors associated with the prevalence of antibodies against Theileria equi in equids of Western Pará, Brazil

The State of Pará has one of the largest herds of equids (horse, donkey and mule) in Brazil, most of these animals are found on cattle farms. Equine theileriosis is a tick‐borne disease caused by the parasite Theileria equi and is characterized by fever, anaemia, icterus, intravascular haemolysis, haemoglobinuria, spleen and hepatomegaly, and even death. The present study aimed to determine the prevalence of antibodies against T. equi in equids in the western region of the State of Pará, Brazil, and to identify potential risk factors associated with parasite infection. A cross‐sectional study was conducted with cluster sampling of farm horses from 18 municipalities. In the cities visited, samples from sport and carthorses were also included. Serum was obtained to detect T. equi‐specific antibodies using an indirect enzyme‐linked immunosorbent assay (iELISA) based on a crude parasite antigen. In order to identify possible risk factors of the infection which are associated with the prevalence of antibodies, a chi‐squared test was carried out. Of 1,117 equids, 373 tested positive for T. equi antibodies with an overall prevalence of 33.4% (31.3%–37.0% for the 95% confidence interval). Sex, animal species and breed were found not to be associated with the presence of T. equi antibodies, whereas age, the presence of dogs or ticks were associated with seropositivity (p < 0.05). Horses with ticks were 2.4 more likely seropositive than horses without ticks. The presence of dogs in the equid habitat and the presence of ticks resulted in a higher T. equi seropositive rate probably because dogs are hosts for vector ticks of T. equi. Our study represents the first report of T. equi antibodies in equids of western Pará revealing a widespread distribution of seropositive animals.     

High Prevalence of Anaplasma spp. in Small Ruminants in Morocco

The prevalence of infection by Anaplasma spp. (including Anaplasma phagocytophilum) was determined using blood smear microscopy and PCR through screening of small ruminant blood samples collected from seven regions of Morocco. Co‐infections of Anaplasma spp., Babesia spp, Theileria spp. and Mycoplasma spp. were investigated and risk factors for Anaplasma spp. infection assessed. A total of 422 small ruminant blood samples were randomly collected from 70 flocks. Individual animal (breed, age, tick burden and previous treatment) and flock data (GPS coordinate of farm, size of flock and livestock production system) were collected. Upon examination of blood smears, 375 blood samples (88.9%) were found to contain Anaplasma‐like erythrocytic inclusion bodies. Upon screening with a large spectrum PCR targeting the Anaplasma 16S rRNA region, 303 (71%) samples were found to be positive. All 303 samples screened with the A. phagocytophilum‐specific PCR, which targets the msp2 region, were found to be negative. Differences in prevalence were found to be statistically significant with regard to region, altitude, flock size, livestock production system, grazing system, presence of clinical cases and application of tick and tick‐borne diseases prophylactic measures. Kappa analysis revealed a poor concordance between microscopy and PCR (k = 0.14). Agreement with PCR is improved by considering microscopy and packed cell volume (PCV) in parallel. The prevalence of double infections was found to be 1.7, 2.5 and 24% for Anaplasma‐Babesia, Anaplasma‐Mycoplasma and Anaplasma‐Theileria, respectively. Co‐infection with three or more haemoparasites was found in 1.6% of animals examined. In conclusion, we demonstrate the high burden of anaplasmosis in small ruminants in Morocco and the high prevalence of co‐infections of tick‐borne diseases. There is an urgent need to improve the control of this neglected group of diseases.     

Bovine anaplasmosis and tick‐borne pathogens in cattle of the Galapagos Islands

A cross‐sectional study was conducted to determine the species of Anaplasma spp. and estimate its prevalence in cattle of the three main cattle‐producing Galapagos Islands (Santa Cruz, San Cristóbal and Isabela) using indirect PCR assays, genetic sequencing and ELISA . Ticks were also collected from cattle and scanned for 47 tick‐borne pathogens in a 48 × 48 real‐time PCR chip. A mixed effects logistic regression was performed to identify potential risk factors explaining Anaplasma infection in cattle. A. phagocytophilum was not detected in any of the tested animals. Genetic sequencing allowed detection of A. platys ‐like strains in 11 (36.7%) of the 30 Anaplasma spp.‐positive samples analysed. A. marginale was widespread in the three islands with a global between‐herd prevalence of 100% [89; 100]_95%CI and a median within‐herd prevalence of 93%. A significant association was found between A. marginale infection and age with higher odds of being positive for adults (OR = 3.3 [1.2; 9.9]_{95% Bootstrap CI} ). All collected ticks were identified as Rhipicephalus microplus. A. marginale , Babesia bigemina , Borrelia theileri and Francisella ‐like endosymbiont were detected in tick pools. These results show that the Galapagos Islands are endemic for A. marginale .     

Development and Application of a Loop‐mediated Isothermal Amplification Assay for Rapid Detection of Borrelia burgdorferi s. l. in Ticks

A loop‐mediated isothermal amplification (LAMP) assay was developed to detect Borrelia burgdorferi s. l. in ticks, which is a pathogen that causes Lyme disease. Cross‐reactions with Chlamydia psittaci, Mycoplasma mycoides subsp. capri and some tick‐borne pathogens were excluded. Analytical sensitivity of LAMP showed its detection limit was from 0.02 to 0.2 pg of DNA in detection of the reference samples at 65°C for 40 min. The performance of LAMP was assessed by testing 110 samples from susceptible tick species and comparing the results with conventional and nested PCR tests previously described. The results demonstrated that LAMP was significantly more sensitive than the conventional PCR (32.7% versus 15.5%, P < 0.05) and slightly more sensitive, although not significantly so, than nested PCR (32.7% versus 26.4%, P > 0.05). The assay was used to analyse a total of 1052 ticks collected from eight provinces in China. The results showed that the infection rates of B. burgdorferi s. l. varied from 12.5% to 88.9% across the different geographical sites. Selected positive samples were subjected to sequencing and sequence analysis for conformation of the accuracy of the assay. Here we report a highly sensitive, specific and easy diagnostic assay based on LAMP technology. These data indicate that LAMP is a useful approach for detecting B. burgdorferi s. l. in field‐collected ticks and has the potential as an alternative tool for the ecological and epidemiological surveillance of Lyme disease.     

Molecular detection and genetic diversity of Bartonella species in large ruminants and associated ectoparasites from the Brazilian Cerrado

Currently, five Bartonella species and an expanding number of Candidatus Bartonella species have globally been reported in ruminants. Likewise, different Bartonella genotypes were identified. However, studies relating to ruminant‐associated Bartonella in Brazil are scarce. The current study aimed to assess the prevalence and genetic diversity of Bartonella in cattle, buffaloes and associated ectoparasites in Brazil. For this purpose, EDTA‐blood samples from 75 cattle and 101 buffaloes were sampled. Additionally, 128 Rhipicephalus microplus and one Amblyomma sculptum ticks collected from cattle, and 197 R. microplus, one A. sculptum and 170 lice (Haematopinus tuberculatus) collected from buffaloes were included. Bartonella DNA was initially screened through an HRM real‐time PCR assay targeting the 16S–23S internal transcribed spacer (ITS), and the positive samples were submitted to an additional HRM assay targeting the ssrA gene. The HRM‐positive amplicons were sequenced, and the nucleotide identity was assessed by BLASTn. Bartonella spp.‐positive DNA samples were analysed by conventional PCR assays targeting the gltA and rpoB genes, and then, the samples were cloned. Finally, the phylogenetic positioning and the genetic diversity of clones were assessed. Overall, 21 of 75 (28%) cattle blood samples and 13 of 126 (10.3%) associated ticks were positive for Bartonella bovis. Out of 101 buffaloes, 95 lice and 188 tick DNA samples, one (1%) buffalo and four (4.2%) lice were positive for Bartonella spp. Conversely, none of the ticks obtained from buffaloes were positive for Bartonella. The Bartonella sequences from buffaloes showed identity ranging from 100% (ITS and gltA) to 94% (ssrA) with B. bovis. In contrast, the Bartonella DNA sequences from lice were identical (100%) to uncultured Bartonella sp. detected in cattle tail louse (Haematopinus quadripertusus) from Israel in all amplified genes. The present study demonstrates the prevalence of new B. bovis genotypes and a cattle lice‐associated Bartonella species in large ruminants and their ectoparasites from Brazil. These findings shed light on the distribution and genetic diversity of ruminant‐ and ectoparasite‐related Bartonella in Brazil.     

A comparison of the efficacy of two commercial acaricides (fipronil and amitraz) with Azadirachta indica (neem) on the brown dog tick (Rhipicephalus sanguineus) from canines in Trinidad

The brown dog tick (Rhipicephalus sanguineus) is prevalent on canids in Trinidad. It is directly (by causing anaemia) and indirectly (by acting as a vector of tick‐borne pathogens) responsible for morbidity and mortalities in the canine population. The most commonly used commercial acaricides available to pet owners in Trinidad are amitraz and fipronil. Often, these acaricides may be abused and misused in a desperate attempt to rid pets of ticks. The objective of this study was to compare the efficacy of amitraz and fipronil with the herbal alternative, neem (Azadirachta indica). Triplicate in vitro trials utilizing the Larval Packet Test (LPT) were conducted using three concentrations (low, recommended and high) of fipronil (0.025%, 0.05% and 0.1%), amitraz (0.01%, 0.02% and 1%), neem oil (10%, 20% and 40%) and neem leaf extract (0.25%, 0.5% and 2%) for each trial. Statistical analysis using the mixed‐effect Poisson regression analysis indicated that there was a significant difference (p < .05) in the survival of ticks pre‐treatment versus post‐treatment with amitraz, fipronil and all controls when compared to the neem oil. Fipronil and amitraz caused ≥99% mortality for all concentrations used in this study. Mortalities for neem oil and neem leaf extract ranged from 72.7% to 82% and 38% to 95.3%, respectively, with the greatest percentage of mortalities occurring at the lower concentrations. Neem oil and neem leaf extract can be used as alternative acaricides, and however, they are less efficacious against the brown dog tick than amitraz and fipronil.     

Seroepidemiological and molecular investigation of spotted fever group rickettsiae and Coxiella burnetii in Sao Tome Island: A One Health approach

Spotted fever group rickettsiae (SFGR) and Coxiella burnetii are intracellular bacteria that cause potentially life‐threatening tick‐borne rickettsioses and Q fever respectively. Sao Tome and Principe (STP), small islands located in the Gulf of Guinea, recently experienced a dramatic reduction in the incidence of malaria owing to international collaborative efforts. However, unexplained febrile illnesses persist. A One Health approach was adopted to investigate exposure to SFGR and C. burnetii in humans and examine the diversity of these bacteria in ticks parasitizing domestic ruminants. A cross‐sectional human serological study was conducted in Agua Grande district in Sao Tome Island from January to March 2016, and ticks were collected from farmed domestic ruminants in 2012 and 2016. In total, 240 individuals varying in age were randomly screened for exposure to SFGR and C. burnetii by indirect immunofluorescence assay. Twenty of 240 individuals (8.3%) were seropositive for SFGR (4 for Rickettsia africae and 16 for R. conorii) and 16 (6.7%) were seropositive for C. burnetii. Amblyomma astrion were collected exclusively in 2012, as were A. variegatum in 2016 and Rickettsia spp. were detected in 22/42 (52.4%) and 49/60 (81.7%) respectively. Sequence analysis of multiple gene targets from Rickettsia spp. detected in ticks suggests the presence of a single divergent R. africae strain (Sao Tome). While no ticks were found positive for C. burnetii, Coxiella‐like endosymbionts were detected in nearly all ticks. This is the first study in STP to provide serological evidence in humans of SFGR and C. burnetii and additional molecular evidence in ticks for SFGR, which may be responsible for some of the unexplained febrile illnesses that persist despite the control of malaria. Future epidemiological studies are needed to confirm the occurrence and risk factors associated with SFG rickettsioses and Q fever in both humans and animals.     

The seroprevalence of Anaplasma phagocytophilum in global human populations: A systematic review and meta‐analysis

The tick‐borne pathogen Anaplasma phagocytophilum is an emerging infectious disease threat, but the overall A. phagocytophilum seroprevalence in humans is unclear. We performed a systematic search of English databases for literature published from 1994 to 2018. Studies reporting serological evidence of A. phagocytophilum infection in humans were included, and the information was extracted by two authors independently. As the study heterogeneity was significant, a random‐effects model was used to calculate the overall pooled seroprevalence. Data from 56 studies involving 28,927 individuals from four continents were included. The seroprevalence reported by the studies ranged from 0% to 37.26%. The overall pooled A. phagocytophilum seroprevalence in humans was 8.4% (95% CI: 6.6%–10.4%). The seroprevalence was highest in high‐risk population (13.8%) and lowest in healthy population (5.0%). The estimated A. phagocytophilum seroprevalence of febrile patient, tick‐bitten and tick‐borne diseases populations was 6.4%, 8.0% and 9.0%, respectively. This meta‐analysis demonstrated first A. phagocytophilum seroprevalence estimates in different populations (healthy, febrile patient, high‐risk, tick‐bitten and tick‐borne diseases populations); it seems likely that present surveillance efforts are missing mild or asymptomatic infections of humans.     

Tick‐borne pathogens in ticks (Acari: Ixodidae) collected from various domestic and wild hosts in Corsica (France), a Mediterranean island environment

Corsica is a mountainous French island in the north‐west of the Mediterranean Sea presenting a large diversity of natural environments where many interactions between humans, domestic animals and wild fauna occur. Despite this favourable context, tick‐borne pathogens (TBPs) have not systematically been investigated. In this study, a large number of TBPs were screened in ticks collected over a period of one year from domestic and wild hosts in Corsica. More than 1,500 ticks belonging to nine species and five genera (Rhipicephalus, Hyalomma, Dermacentor, Ixodes and Haemaphysalis) were analysed individually or pooled (by species, gender, host and locality). A real‐time microfluidic PCR was used for high‐throughput screening of TBP DNA. This advanced methodology enabled the simultaneous detection of 29 bacterial and 12 parasitic species (including Borrelia, Anaplasma, Ehrlichia, Rickettsia, Bartonella, Candidatus Neoehrlichia, Coxiella, Francisella, Babesia and Theileria). The Crimean–Congo haemorrhagic fever (CCHF) virus was investigated individually in tick species known to be vectors or carriers of this virus. In almost half of the tick pools (48%), DNA from at least one pathogen was detected and eleven species of TBPs from six genera were reported. TBPs were found in ticks from all collected hosts and were present in more than 80% of the investigated area. The detection of DNA of certain species confirmed the previous identification of these pathogens in Corsica, such as Rickettsia aeschlimannii (23% of pools), Rickettsia slovaca (5%), Anaplasma marginale (4%) and Theileria equi (0.4%), but most TBP DNA identified had not previously been reported in Corsican ticks. This included Anaplasma phagocytophilum (16%), Rickettsia helvetica (1%), Borrelia afzelii (0.7%), Borrelia miyamotoi (1%), Bartonella henselae (2%), Babesia bigemina (2%) and Babesia ovis (0.5%). The high tick infection rate and the diversity of TBPs reported in this study highlight the probable role of animals as reservoir hosts of zoonotic pathogens and human exposure to TBPs in Corsica.     

First detection of Theileria parva in cattle from Cameroon in the absence of the main tick vector Rhipicephalus appendiculatus

A major risk factor for the spread of livestock diseases and their vectors is the uncontrolled transboundary movement of live animals for trade and grazing. Such movements constrain effective control of tick‐transmitted pathogens, including Theileria parva. Only limited studies have been undertaken to identify ticks and tick‐borne diseases (TTBDs) affecting cattle in central African countries, including Cameroon. We hereby report the collection of baseline data on the prevalence of T. parva in Cameroon through a countrywide cross‐sectional survey, conducted in 2016, involving collection of blood samples from cattle from 63 sites across the five agro‐ecological zones (AEZs) of the country. ELISA‐based surveillance of infected cattle was performed on 479 randomly selected samples and revealed specific antibodies to T. parva in 22.7% and T. mutans in 41.1% of cattle. Screening of 1,340 representative DNA samples for the presence of T. parva identified 25 (1.86%) positives using a p104 antigen gene‐based nested PCR assay. The positives were distributed across agro‐ecological zones I, II, III and V. None of the p104 positive cattle exhibited clinical symptoms of East Coast fever (ECF). Using reverse line blot (RLB), 58 (4.3%) and 1,139 (85%) of the samples reacted with the T. parva and T. mutans oligonucleotide probes, respectively. This represents the first report of T. parva from Cameroon. Surprisingly, no Rhipicephalus appendiculatus ticks, the main vector of T. parva, were identified in a parallel study involving comprehensive morphological and molecular survey of tick species present in the country. Only two of the 25 p104 positive cattle were PCR‐positive for the CD8+ T‐cell target schizont‐expressed antigen gene Tp1. Cloning and sequencing of Tp1 amplicons revealed sequence identity with the reference T. parva Muguga. This new finding raises serious concerns of a potential spread of ECF into the central African region.