Search Results (44)

Gastrointestinal parasites (GIPs) and tick infestations remain critical health challenges limiting cattle productivity in rural South Africa, particularly within communal farming systems. The Eastern Cape Province, characterized by high livestock densities and variable management practices, provides a unique context in which to examine parasitic burdens across systems. This study aimed to compare the prevalence, intensity, and diversity of GIPs and tick species in cattle raised under rural communal grazing versus communal feedlot systems in the Eastern Cape Province of South Africa. A total of 160 cattle (n = 80 per system) were randomly selected for fecal and tick examinations in community-based feedlots in Holela (Centane) and Gxwalibomvu (Tsomo), as well as from surrounding rural villages. Fecal samples were analyzed using the McMaster technique to determine fecal egg counts (FEC), while tick species were identified and counted from standardized body regions. Body condition scores (BCS) were recorded, and farmer practices related to parasite control were surveyed. Results showed significantly higher GI parasite prevalence and FEC in rural community cattle compared to feedlot cattle (p < 0.05), with Haemonchus contortus and Trichostrongylus spp. being the most prevalent. Similarly, rural cattle had significantly higher tick infestation rates, dominated by Rhipicephalus microplus and Amblyomma hebraeum. Logistic regression identified rural production system, poor body condition (BCS ≤ 2), and absence of recent deworming as significant risk factors for GI parasitism (p < 0.05). Strong negative correlations were found between BCS and both FEC (r = −0.63) and tick burden (r = −0.57). Additionally, rural farmers reported lower acaricide usage and greater reliance on traditional remedies. The study confirms that rural communal systems expose cattle to higher parasitic risks due to unmanaged grazing, limited veterinary support, and poor parasite control strategies. Communal feedlots, by contrast, offer more controlled conditions that reduce parasitic burden. Integrating strategic parasite management, farmer training, and expanded veterinary outreach is essential to improving cattle health and productivity in communal areas. Full article

This study sought to investigate the presence of anti-Rickettsia spp. antibodies in georeferenced serum samples from equids across all regions of the state of Goiás, while also presenting variables that indicate risk factors for the circulation of rickettsiae, and evaluating the presence of rickettsial DNA in ticks collected from equids and the surrounding environment in the municipalities of Uruaçu and Porangatu, located in the northern region of the state. A total of 1156 equid serum samples provided by the Goiás Agricultural Defense Agency (Agrodefesa) were analyzed for antibodies against 4 Rickettsia antigens. Additionally, 39 blood samples were collected from equids during a 3-day field expedition in January 2024, alongside 938 ticks collected from both animals and the environment. In total, 297 adult ticks were randomly selected for molecular analysis and tested by qPCR targeting the rickettsial gltA gene. Positive samples were further analyzed using cPCR to target the ompA and gltA genes. Results revealed that 9.6% (111/1156) of the serum samples were seroreactive to at least one Rickettsia antigen. Among these, 36% had antibodies against Rickettsia rickettsii, 18.9% against Rickettsia parkeri, 69.4% against Rickettsia amblyommatis, and 14.4% against Rickettsia bellii. Furthermore, the possible antigen responsible for a homologous reaction was found in 3.6% of equids for R. rickettsii, and in the same proportion for R. bellii, while 23.4% of animals showed antibodies for R. amblyommatis, and none exhibited a homologous reaction to R. parkeri. Meanwhile, 28.2% of the serum samples collected during the field expedition had antibodies against R. amblyommatis, with 72.7% identifying R. amblyommatis as the antigen involved in the homologous reaction. In the logistic regression analysis, the variables of education level, altitude below 500 m, and presence of female mules demonstrated a positive effect on seropositivity. Ticks from animals were identified as Amblyomma cajennense sensu lato, Amblyomma sculptum, Dermacentor nitens, and Rhipicephalus microplus, while environmental ticks were identified as A. cajennense s.l., A. sculptum, and Amblyomma nodosum. In the qPCR assays, two specimens of A. cajennense s.l., one of A. sculptum, and one of D. nitens amplified a fragment of the gltA gene. Of these, one A. cajennense s.l. specimen amplified a fragment of both the ompA and gltA genes, and one A. sculptum specimen amplified a fragment of the gltA gene through conventional PCR. Sequencing confirmed the detection of R. amblyommatis. These findings highlight the presence of anti-Rickettsia spp. antibodies in equid serum samples from all regions of the state of Goiás, emphasizing the important role of equids as sentinels for Rickettsia spp. To our knowledge, this study represents the largest effort to detect anti-Rickettsia spp. antibodies in equid serum samples in Brazil. Additionally, it is the first nationwide investigation of its kind conducted in collaboration with the Agricultural Defense Agency (Agrodefesa), serving as a significant example of the One Health approach. Full article

(1) Background: Brazilian spotted fever (BSF) is a tick-borne disease that has occurred in several Brazilian regions, caused by Rickettsia spp. bacteria and mainly transmitted by Amblyomma ticks. Despite the high BSF lethality in several Brazilian endemic areas, predictors and associated risk factors remain to be fully established. Accordingly, the retrospective study herein aimed to assess BSF cases and associated factors in an endemic area of western São Paulo state. (2) Methods: Notified cases identified by the System for Epidemiological Surveillance of São Paulo (CVE), from January 2007 to December 2021, were gathered and analyzed by Logistic Multivariate Regression (LMR) to assess potential risk factors for BSF. (3) Results: Overall, 74/1121 (6.6%; 95% CI: 5.29–8.21) individuals were considered positive for BSF. Univariate analysis showed previous contact with capybaras (OR: 1.89; 95% CI: 1.0–3.55; p < 0.001) and raising horses (OR = 1.4; 95% CI: 0.66–2.67; p = 0.45), while LMR revealed living in rural areas (OR = 2.0; 95% CI: 1.02–3.73; p = 0.037) as an associated risk factor for BSF. (4) Conclusions: The results herein show that the geographically studied area still shows high occurrence of BSF, mostly for individuals living or visiting areas overlapping free-ranging capybaras. Full article

Ticks are well-known vectors of pathogens, posing considerable risks to livestock health and productivity. In Cameroon, where livestock production is vital, established tick species such as Amblyomma variegatum and Hyalomma truncatum are prevalent in key cattle-rearing areas. The recent introduction of the invasive, acaricide-resistant Rhipicephalus microplus further complicates control efforts. In this study, we deliver baseline data on the composition of tick species and their shifts within agroecological zone I (AEZ I) and agroecological zone III (AEZ III) of Cameroon, providing a foundation for targeted vector control strategies to ultimately reduce the risk of pathogen transmission. From 1100 ticks collected across two Cameroonian agroecological zones, H. truncatum (39.9%), A. variegatum (31%), and R. microplus (10.64%) were the most prevalent species, along with Rhipicephalus lunulatus (4.45%), Hyalomma rufipes (1.45%), Hyalomma marginatum (1.09%), Hyalomma dromedarii (0.45%), and Rhipicephalus sanguineus (0.9%). Molecular identification using cytochrome C oxidase subunit 1 (cox1) and 16s led to the identification of five additional species, Hyalomma nitidum (0.73%), Rhipicephalus simus (3.54%), Rhipicephalus sulcatus (2.64%), Rhipicephalus praetextatus (2.1%), and Rhipicephalus pusillus (1.1%). R. microplus emerged as the most dominant Rhipicephalus spp. in AEZ I, comprising 67.5% of the total Rhipicephalus ticks. In conclusion, we demonstrate the further spread of R. microplus, which represents a major source of vector-borne diseases, affecting both humans and animals. Full article

Hard ticks (family Ixodidae) are one of the most predominant arthropod disease vectors worldwide, second only to mosquitoes. In addition to harboring animal and human pathogens, ticks are known to carry a microbial community constituted of non-pathogenic organisms, which includes maternally inherited intracellular endosymbionts and other environmentally acquired extracellular microorganisms. These microbial communities, which include bacteria, viruses, protozoans, and fungi—with often commensal, mutualistic, or parasitic associations with the tick—comprise the tick microbiome, bacteria being the most studied community. Many bacterial taxa frequently reported in ticks include soil, plant, and animal-associated microbes, suggesting many are environmentally acquired, including members with known entomopathogenic potential, such as Bacillus thuringiensis, Bacillus spp., and Pseudomonas spp. It has been reported that microbial community composition can impact pathogen persistence, dissemination, and fitness in ticks. In the United States, Ixodes scapularis (northeast) and I. pacificus (west) are the predominant vectors of Borrelia burgdorferi, the causal agent of Lyme disease. Amblyomma americanum is another important tick vector in the U.S. and is becoming an increasing concern as it is the leading cause of alpha-gal syndrome (AGS, or red meat allergy). This condition is caused by tick bites containing the galactose alpha 1,3 galactose (alpha-gal) epitope in their saliva. In this paper, we present a summary of the tick microbiome, including the endosymbiotic bacteria and the environmentally acquired (here referred to as the non-endosymbiotic community). We will focus on the non-endosymbiotic bacteria from Ixodes spp. and Amblyomma americanum and discuss their potential for novel biocontrol strategies. Full article

Anaplasmataceae bacteria are emerging infectious agents transmitted by ticks. The aim of this study was to identify the molecular diversity of this bacterial family in ticks and hosts, both domestic and wild, as well as blood meal sources of free-living ticks in northeastern Paraguay. The bacteria were identified using PCR-HRM, a method optimized for this purpose, while the identification of ticks and their blood meal was performed using conventional PCR. All amplified products were subsequently sequenced. The bacteria detected in the blood hosts included Ehrlichia canis, Anaplasma platys, and Anaplasma phagocytophilum, Candidatus Anaplasma boleense, and Wolbachia spp., which had not been previously reported in the country. Free-living and parasitic ticks on dogs (Canis lupus familiaris) and wild armadillos (Dasypus novemcinctus) were collected and identified as Rhipicephalus sanguineus and Amblyomma spp. The species E. canis, A. platys, A. phagocytophilum, and Ca. A. boleense were detected in domestic dog ticks, and E. canis and A. platys were found for the first time in armadillos and free-living ticks. Blood feeding sources detected in free-living ticks were rodents, humans, armadillos and dogs. Results show a high diversity of tick-borne pathogens circulating among domestic and wild animals in the northeastern region of Paraguay. Full article

Tick-borne rickettsioses are considered among the oldest known vector-borne zoonotic diseases. Among the rickettsiae, Rickettsia africae is the most reported and important in Africa, as it is the aetiological agent of African tick bite fever (ATBF). Studies describing the prevalence of R. africae in southern Africa are fragmented, as they are limited to small geographical areas and focused on Amblyomma hebraeum and Amblyomma variegatum as vectors. Amblyomma spp. ticks were collected in Angola, Mozambique, South Africa, Zambia and Zimbabwe during the sampling period from March 2020 to September 2022. Rickettsia africae was detected using the ompA gene, while characterisation was conducted using omp, ompA, ompB and gltA genes. In total, 7734 Amblyomma spp. ticks were collected and were morphologically and molecularly identified as Amblyomma eburneum, A. hebraeum, Amblyomma pomposum and A. variegatum. Low levels of variability were observed in the phylogenetic analysis of the R. africae concatenated genes. The prevalence of R. africae ranged from 11.7% in South Africa to 35.7% in Zambia. This is one of the largest studies on R. africae prevalence in southern Africa and highlights the need for the inclusion of ATBF as a differential diagnosis when inhabitants and travellers present with flu-like symptoms in the documented countries. Full article

Wild boars (Sus scrofa L.) are considered among the most harmful invasive species worldwide, causing irreversible ecosystem damage, acting as zoonotic spreaders and reservoirs, threatening human and animal health, and having an important economic impact. Accordingly, the present study has assessed the rickettsial exposure, tick infestation of wild boars, and rickettsial DNA presence in ticks from infested animals from the Cerrado biome in midwestern Brazil. Anti-Rickettsia spp. antibodies were detected in serum samples of wild boars by immunofluorescence assay. Overall, 106/285 (37.2%) wild boar serum samples from 13 to 18 (72.2%) municipalities showed seroreactivity to at least one of the four Rickettsia spp. antigens tested, the largest number of wild boars serologically tested to Rickettsia spp. in this type of study. Among the 106 seroreactive animals, 34 showed possible homologous reactions between R. parkeri, R. amblyommatis, and R. bellii, with endpoint titers between 128 and 512. A sample of 45 ticks collected from four culled wild boars was identified as Amblyomma sculptum, and all tested negative for rickettsial DNA presence. In conclusion, this study has provided a reliable sampling seroprevalence and indicated high exposure of wild boars to rickettsial agents, with a potential interaction with Rickettsia spp. from the spotted fever group within the Cerrado biome from midwestern Brazil. Full article

Eight hunting dogs were visited by a state veterinarian on the island of Tobago, Trinidad and Tobago, West Indies, as owners reported anorexia and paralysis in five of their dogs. The veterinarian observed a combination of clinical signs consistent with tick-borne illness, including fever, anorexia, anaemia, lethargy and paralysis. Blood and ticks were collected from each dog and submitted to a diagnostic laboratory for analysis. Microscopic analysis revealed a mixed infection of intracytoplasmic organisms consistent with Babesia spp. (erythrocyte) and Ehrlichia spp. (monocyte), respectively, from one dog, while a complete blood count indicated a regenerative anaemia (n = 1; 12.5%), non-regenerative anaemia (n = 4; 50%), neutrophilia (n = 3; 37.5%), lymphocytosis (n = 2; 25%), thrombocytopaenia (n = 3; 37.5%) and pancytopaenia (n = 1; 12.5%). DNA isolated from the eight blood samples and 20 ticks (16 Rhipicephalus sanguineus and 4 Amblyomma ovale) were subjected to conventional PCR and next-generation sequencing of the 16S rRNA and 18S rRNA gene for Anaplasma/Ehrlichia and Babesia/Theileria/Hepatozoon, respectively. The DNA of Ehrlichia spp., closely related to Ehrlichia canis, was detected in the blood of three dogs (37.5%), Anaplasma spp., closely related to Anaplasma marginale, in two (25%), Babesia vogeli in one dog (12.5%) and seven ticks (35%) and Hepatozoon canis and Anaplasma spp., in one tick (5%), respectively. These findings highlight the need to test both the vector and host for the presence of tick-borne pathogens when undertaking diagnostic investigations. Further studies are also warranted to elucidate the susceptibility of canids to Anaplasma marginale. Full article

This study was carried out from February 2020 to September 2021 in Parque Nacional das Emas (PNE), a national park located in the Cerrado biome, midwestern Brazil, as well as in surrounding rural properties. Serum and tick samples were collected from dogs, terrestrial small mammals, and humans. Ticks were also collected from the environment. Dogs were infested with Rhipicephalus linnaei adults, whereas small mammals were infested by immature stages of Amblyomma spp., Amblyomma triste, Amblyomma dubitatum, and Amblyomma coelebs. Ticks collected from vegetation belonged to several species of the genus Amblyomma, including A. coelebs, A. dubitatum, Amblyomma naponense, Amblyomma sculptum, and A. triste. Two Rickettsia species were molecularly detected in ticks: Rickettsia parkeri in A. triste from the vegetation and a Rickettsia sp. (designated Rickettsia sp. strain PNE) in A. sculptum and A. triste collected from lowland tapirs (Tapirus terrestris). Based on short gltA gene fragments, this rickettsial organism showed 99.7–100% to Rickettsia tillamookensis. Seroreactivity to Rickettsia antigens was detected in 21.9% of dogs, 15.4% of small mammals, and 23.5% of humans. The present study reveals the richness of ticks and demonstrates the circulation of rickettsial agents in one of the largest conservation units in the Cerrado biome in Brazil. To our knowledge, this is the first report of a rickettsial phylogenetically related to R. tillamookensis in Brazil. Full article

Ticks and tick-borne diseases affect livestock productivity and cause significant economic losses. Therefore, surveillance of these pathogens and vectors is paramount to reducing these effects in livestock. This study aimed to identify Anaplasma marginale and Borrelia burgdorferi sensu lato in ticks collected from cattle. Molecular biology techniques were utilized to identify A. marginale for both types of samples, i.e., ticks and bovine blood. Serology of cattle using indirect immunofluorescence assay (IFA) was conducted to determine antibodies to B. burgdorferi s.l. from seven locations in Nuevo Leon, Mexico, between 2015 and 2017. From 404 bovines, 2880 ticks were collected: Rhipicephalus microplus (2391 females and 395 males), Amblyomma spp. (51 females and 42 males) and Dermacentor variabilis (1 female). Rhipicephalus microplus represented the largest specimens captured, with 96.7% within the seven study sites. PCR processed only 15% (442) of tick samples to identify A. marginale. Field genera proportions were followed to select testing tick numbers. Results showed that 9.9% (44/442) of A. maginale infected the pooled tick species, whereas the highest percent corresponded to 9.4% (38/404) in R. microplus. Regarding the molecular analysis of blood samples, 214 of 337 (63.5%) were positive for A. maginale. In each of the seven locations, at least one bovine sample tested positive for A. maginale. Borrelia burgdorferi s.l. was not found either in the ticks or serum samples. Two A.marginale DNA nucleotide sequences obtained in this study were deposited in the GenBank with the following accession numbers OR050501 cattle, and OR050500 R.microplus tick. Results of this work point to current distribution of bovine anaplasmosis in northern Mexico. Full article

Species of Ixodiphagus (Hymenoptera: Encyrtidae) are parasitoid wasps whose immature forms develop inside ixodid and argasid ticks (Acari: Ixodida). Following oviposition by adult female wasps into the idiosoma of ticks, larvae hatch and start feeding on their internal contents, eventually emerging as adult wasps from the body of the dead ticks. Species of Ixodiphagus have been reported as parasitoids of 21 species of ticks distributed across 7 genera. There are at least ten species described in the genus, with Ixodiphagus hookeri being the most studied as an agent for biological control of ticks. Although attempts of tick control by means of this parasitoid largely failed, in a small-scale study 150,000 specimens of I. hookeri were released over a 1-year period in a pasture where a small cattle population was kept, resulting in an overall reduction in the number of Amblyomma variegatum ticks per animal. This review discusses current scientific information about Ixodiphagus spp., focusing on the role of this parasitoid in the control of ticks. The interactions between these wasps and the ticks’ population are also discussed, focusing on the many biological and logistical challenges, with limitations of this control method for reducing tick populations under natural conditions. Full article

Brazilian spotted fever (BSF) is the most important tick-borne diseases affecting humans in Brazil. Cases of BSF have recently been reported in the Goiás state, midwestern Brazil. All cases have been confirmed by reference laboratories by seroconversion to Rickettsia rickettsii antigens. Because serological cross-reactions among different rickettsial species that belong to the spotted fever group (SFG) are common, the agent responsible for BSF cases in Goiás remains unknown. From March 2020 to April 2022, ticks and plasma were collected from dogs, horses and capybaras (Hydrochoerus hydrochaeris), and from the vegetation in an area where BSF cases have been reported and two areas under epidemiological surveillance in Goiás. Horses were infested by Amblyomma sculptum, Dermacentor nitens and Rhipicephalus microplus; dogs by Rhipicephalus sanguineus sensu lato (s.l.), Amblyomma ovale and A. sculptum, and capybaras by A. sculptum and Amblyomma dubitatum. Adults of A. sculptum, A. dubitatum, Amblyomma rotundatum and immature stages of A. sculptum and A. dubitatum, and Amblyomma spp. were collected from the vegetation. DNA of Rickettsia that did not belong to the SFG was detected in A. dubitatum, which was identified by DNA sequencing as Rickettsia bellii. Seroreactivity to SFG and Rickettsia bellii antigens was detected in 25.4% (42/165) of dogs, 22.7% (10/44) of horses and 41.2% (7/17) of capybaras, with higher titers for R. bellii in dogs and capybaras. The seropositivity of animals to SFG Rickettsia spp. antigens demonstrates the circulation of SFG rickettsiae in the region. Further research is needed to fully determine the agent responsible for rickettsiosis cases in this area. Full article

Even though previous works showed molecular evidence of hemotropic Mycoplasma spp. (hemoplasmas) in ring-tailed coatis (Nasua nasua) from Brazil, Bartonella sp. has not been reported in these mammals so far. The present study aimed to detect the above-mentioned agents in coatis’ blood and associated ectoparasites, assessing the association between these infections and red blood parameters. Between March 2018 and January 2019, coati (n = 97) blood samples, Amblyomma sp. ticks (2242 individual ticks, resulting in 265 pools), and Neotrichodectes pallidus louse (n = 59) were collected in forested urban areas from midwestern Brazil. DNA extracted from coatis’ blood, and ectoparasite samples were submitted to quantitative PCR (qPCR) (16S rRNA) and conventional PCR (cPCR) (16S rRNA and 23S rRNA) for hemoplasmas and qPCR (nuoG gene) and culturing (only blood) for Bartonella spp. Two different hemoplasma genotypes were detected in blood samples: 71% coatis positive for myc1 and 17% positive for myc2. While 10% of ticks were positive for hemoplasmas (myc1), no louse was positive. The estimated bacterial load of hemoplasmas showed no association with anemia indicators. All coatis were negative for Bartonella sp. in qPCR assay and culturing, albeit two Amblyomma sp. larvae pools, and 2 A. dubitatum nymph pools were positive in the qPCR. The present work showed a high occurrence of hemoplasmas, with two distinct hemoplasma genotypes, in coatis from forested urban areas in midwestern Brazil. Full article

The present study was performed to survey the dominant tick populations and molecularly determine the pathogenic agents of anaplasmosis in ticks from Gyeongsang, Republic of Korea. A total of 3825 questing ticks were collected by the flagging method from 12 sites near animal farms in Gyeongsang from March to October 2021. A molecular genomic study was performed with ticks stored in 70% ethanol to detect Anaplasma genes by the previously described method. The monthly incidence of ticks varied by developmental stages, i.e., nymphs, adults, and larvae, and each of their populations peaked in May, March, and October, respectively. The predominant tick species were Haemaphysalis longicornis, Haemaphysalis sp., Haemaphysalis flava, Ixodes nipponensis, and Amblyomma testudinarium in order. To determine the Anaplasma infection rate, collected ticks were pooled into 395 groups. The minimum infection rate (MIR) of Anaplasma was 0.7% (27 pools). That of A. phagocytophilum was highest (23 pools, MIR 0.6%), followed by A. phagocytophilum-like Anaplasma spp. clade B (2 pools, MIR 0.1%), A. bovis (1 pool, MIR 0.1%), and A. capra (1 pool, MIR 0.1%), respectively. In this study, five species of ticks, including unidentified Haemaphysalis species, were collected in 12 survey sites in Gyeongsang, but their prevalence was somewhat different according to the tick species and survey sites. Further, the incidence rate (6.8%) of 4 Anaplasma spp. was not as high in tick pools. However, the results of this study may offer a basis for future epidemiological research and risk assessment of tick-borne diseases. Full article