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1.
Microb Pathog ; 192: 106721, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38815776

ABSTRACT

Ticks play an important role in the transmission of parasitic diseases, especially pathogenic protozoa in canine hosts, and it is very important to determine the role and extent of their infection with these pathogens in order to determine important control strategies. This study assessed the molecular prevalence of three protozoan pathogens including Hepatozoon canis, Leishmania spp. and Babesia spp., in ticks using PCR. A total 300 stray dogs were investigated and 691 ticks (171 male, 377 female and 143 nymph) were detected directly from 45 infested dogs. Species, stage of growth, and gender were determined for each tick. DNA extracted from 224 ticks (26 male, 165 female and 33 nymph). The molecular presence of three protozoan pathogens including Hepatozoon spp. (18S rRNA gene), Leishmania infantum (kinetoplastid minicircle DNA) and Babesia spp. (ssrRNA gene) were investigated using PCR method. One species of ticks, Rhipicephalus sanguineus was identified. Two of the target pathogens, Hepatozoon spp. (7/83; 8.43 %) and Babesia spp. (1/83; 1.2 %), were detected by PCR method. Sequence analysis of the ssrRNA gene of detected Babesia spp. showed a close relationship to the deposited strains of Babesia vulpis in the gene bank. To the best of our knowledge, this is the first study to undertake a phylogenetic analysis of H. canis and Babesia spp. in stray dogs in Alborz province, Iran and the first report about molecular detection of Babesia vulpis from tick infesting dogs in Iran. According to the above results, it seems necessary to implement tick control programs in dogs.


Subject(s)
Babesia , Dog Diseases , Phylogeny , RNA, Ribosomal, 18S , Animals , Dogs , Iran/epidemiology , Dog Diseases/parasitology , Dog Diseases/epidemiology , Babesia/genetics , Babesia/isolation & purification , Babesia/classification , Female , Male , RNA, Ribosomal, 18S/genetics , DNA, Protozoan/genetics , Polymerase Chain Reaction , Rhipicephalus sanguineus/parasitology , Ticks/parasitology , Eucoccidiida/genetics , Eucoccidiida/isolation & purification , Eucoccidiida/classification , Leishmania infantum/genetics , Leishmania infantum/isolation & purification , Leishmania infantum/classification , Tick Infestations/veterinary , Tick Infestations/epidemiology , Tick Infestations/parasitology , Leishmania/genetics , Leishmania/classification , Leishmania/isolation & purification
2.
PLoS Biol ; 19(1): e3001066, 2021 01.
Article in English | MEDLINE | ID: mdl-33507921

ABSTRACT

Lyme disease is common in the northeastern United States, but rare in the southeast, even though the tick vector is found in both regions. Infection prevalence of Lyme spirochetes in host-seeking ticks, an important component to the risk of Lyme disease, is also high in the northeast and northern midwest, but declines sharply in the south. As ticks must acquire Lyme spirochetes from infected vertebrate hosts, the role of wildlife species composition on Lyme disease risk has been a topic of lively academic discussion. We compared tick-vertebrate host interactions using standardized sampling methods among 8 sites scattered throughout the eastern US. Geographical trends in diversity of tick hosts are gradual and do not match the sharp decline in prevalence at southern sites, but tick-host associations show a clear shift from mammals in the north to reptiles in the south. Tick infection prevalence declines north to south largely because of high tick infestation of efficient spirochete reservoir hosts (rodents and shrews) in the north but not in the south. Minimal infestation of small mammals in the south results from strong selective attachment to lizards such as skinks (which are inefficient reservoirs for Lyme spirochetes) in the southern states. Selective host choice, along with latitudinal differences in tick host-seeking behavior and variations in tick densities, explains the geographic pattern of Lyme disease in the eastern US.


Subject(s)
Disease Vectors , Host-Seeking Behavior/physiology , Lyme Disease/epidemiology , Animals , Animals, Wild , Borrelia burgdorferi/physiology , Climate , Disease Reservoirs/microbiology , Disease Reservoirs/statistics & numerical data , Disease Vectors/classification , Geography , Host Specificity/physiology , Humans , Lizards/microbiology , Lyme Disease/transmission , Mice , Population Density , Prevalence , Rats , Sciuridae/microbiology , Shrews/microbiology , Tick Infestations/epidemiology , Tick Infestations/microbiology , Tick Infestations/transmission , Ticks/microbiology , United States/epidemiology
3.
BMC Vet Res ; 20(1): 119, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38528496

ABSTRACT

BACKGROUND: Rhipicephalus (Boophilus) microplus (Canestrini, 1888), the Asian blue tick, is a highly invasive and adaptable ectoparasite. This tick species has successfully established itself in most regions of the world, with movement of cattle being a major driver for its spread. In the recent past, R. microplus ticks have been reported in three districts of Uganda. Information on its spread and distribution are vital in deepening our understanding of the ecological scenarios that lead to tick persistence and in the formulation of control strategies. This is especially important in the cattle-dense districts. METHODS: We randomly collected tick specimens from 1,461cattle spread across seven cattle dense districts located in the Central, Karamoja and West Nile regions of Uganda from January to September 2020. The ticks were identified using standard morpho-taxonomic keys and the R. microplus tick species identities were confirmed by sequencing of the ITS2 region, 12S rRNA and 16S rRNA genes and phylogenetic analyses. RESULTS: Adult ticks (n = 13,019) were collected from 1,461 cattle. Seventeen tick species were identified based on morpho-taxonomic keys and the majority (47.4%; n=6184) of these were R. appendiculatus. In total, 257 R. microplus ticks were found infesting cattle in 18 study sites in the districts of Amudat, Kaabong, Napak (Karamoja region) and Arua (West Nile region). The identity of R. microplus was confirmed using molecular technics. No R. microplus tick was recorded in the districts of Lyantonde and Nakaseke (Central region). Arua district accounted for 82.1% (n=211) of the R. microplus ticks recorded followed by Napak district at 16.3% (n=42), while Amudat and Kaabong districts accounted for 1.5% (n=4). Rhipicephalus microplus and R. decoloratus co-existed in 6 of the 13 study sites in Arua district, while in another 6 study sites, no R. decoloratus was recorded. In the Karamoja region districts R. decoloratus co-existed with R.microplus. Of the total 618 ticks belonging to four species of the subgenus Boophilus recorded in this study, R. decoloratus accounted for 50.04% (n=334), followed by R. microplus at 41.58% (n=257), R. geigyi at 2.75% (n=17) and R. annulatus at 1.61% (n=10). In the districts of Amudat, Kaabong and Napak, R. decoloratus was more dominant (76.1%; n=179) of the three Rhipicephalus (Boophilus) tick species recorded, followed by R. microplus (19.5%; n=46) and R. geigyi (4.2%; n=10). Contrariwise, R. microplus was more dominant (84%; n=211) in Arua district followed by R. decoloratus (10.7%; n=27), R. annulatus (3.9%; n=10) and R. geigyi (1.1%; n=3). Phylogenetic analyses of the ITS2 region, 12S rRNA and 16S rRNA genes revealed subgrouping of the obtained sequences with the previously published R. microplus sequences from other parts of the world. CONCLUSION: Rhipicephalus microplus ticks were found infesting cattle in four districts of Uganda. The inability to find R. decoloratus, an indigenous tick, from six sites in the district of Arua is suggestive of its replacement by R. microplus. Rhipicephalus microplus negatively affects livestock production, and therefore, there is a need to determine its distribution and to deepen the understanding of the ecological factors that lead to its spread and persistence in an area.


Subject(s)
Cattle Diseases , Rhipicephalus , Tick Infestations , Cattle , Animals , RNA, Ribosomal, 16S/genetics , Tick Infestations/epidemiology , Tick Infestations/veterinary , Uganda/epidemiology , Phylogeny , Tick Control , Cattle Diseases/epidemiology , Cattle Diseases/prevention & control , Cattle Diseases/parasitology
4.
BMC Vet Res ; 20(1): 50, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38326882

ABSTRACT

BACKGROUND: Ticks and tick-borne diseases (TTBDs) are a significant threat to livestock production in sub-Saharan Africa. Transhumance pastoralism practiced in Karamoja region and other factors like cattle trade, communal grazing and the presence of wildlife predispose cattle to TTBDs. Tick species abundance and distribution data can be used as a tool for early disease diagnosis and inform tick control strategies. However, these data for north-eastern Uganda are currently limited; previous surveys were relatively localized and targeted fewer cattle kraals and numbers. METHODS: We randomly collected tick specimens from 1,534 cattle spread across Karamoja region in both the peak month of the rainy (May 2020) and the dry (February2021) seasons. The ticks were identified using morpho-taxonomic keys and the tick species identities confirmed by the 16 S rRNA gene sequencing and phylogenetic analysis. RESULTS: A collection of 18,637 ticks was examined and fifteen tick species from three genera (ten Rhipicephalus; three Amblyomma; two Hyalomma species) were identified. Rhipicephalus appendiculatus was the most dominant (37.9%) tick species, followed by Amblyomma variegatum (32.3%); A. lepidum (17.3%); R. evertsi evertsi (7.8%); and R. decoloratus (1.4%). Eight of these tick species were ubiquitous in the study districts while six were found in isolated areas. The peak month of the dry season collection was associated with a higher proportion of tick-infested cattle (91%) compared to the peak month of the rainy season (89.8%); a difference that was not found statistically significant (χ2 = 0.5077, n = 1385, p = 0.476). The overall cattle infestation rate was mainly dominated by five tick species namely: A. variegatum (55%), R. appendiculatus (53%), A. lepidum (41%), R. evertsi (22%), and R. decoloratus (8%). The proportion of tick-infested cattle was highest in Napak District (95.4%) and lowest in Amudat District (80.9%) during the peak month of the rainy season. Napak and Amudat Districts also had the highest and lowest proportion of tick-infested cattle (94.8% and 80.7% respectively) during the peak month of the dry season. Rhipicephalus microplus was confirmed in Amudat, Kaabong and Napak districts. CONCLUSION: This study demonstrates high tick infestation rates in cattle by a battery of tick species in Karamoja region. We identified both R. microplus and R. decoloratus which indicates that R. microplus has recently been introduced in this region. This calls for effective tick control responses to prevent further spread of this invasive cattle tick specie.


Subject(s)
Cattle Diseases , Ixodidae , Rhipicephalus , Tick Infestations , Tick-Borne Diseases , Animals , Cattle , Prevalence , Uganda/epidemiology , Phylogeny , Cattle Diseases/epidemiology , Tick Infestations/epidemiology , Tick Infestations/veterinary , Tick-Borne Diseases/epidemiology , Tick-Borne Diseases/veterinary , Amblyomma
5.
BMC Vet Res ; 20(1): 279, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38937767

ABSTRACT

Rickettsia occurs worldwide and rickettsiosis is recognized as an emerging infection in several parts of the world. Ticks are reservoir hosts for pathogenic Rickettsia species in humans and domestic animals. Most pathogenic Rickettsia species belong to the spotted Fever Group (SFG). This study aimed to identify and diagnose tick fauna and investigate the prevalence of Rickettsia spp. in ticks collected from domestic animals and dogs in the rural regions of Kerman Province, Southeast Iran. In this study, tick species (fauna) were identified and 2100 ticks (350 pooled samples) from two genera and species including Rhipicephalus linnaei (1128) and Hyalomma deteritum (972) were tested to detect Rickettsia genus using Real-time PCR. The presence of the Rickettsia genus was observed in 24.9% (95%CI 20.28-29.52) of the pooled samples. Sequencing and phylogenetic analyses revealed the presence of Rickettsia aeschlimannii (48.98%), Rickettsia conorii israelensis (28.57%), Rickettsia sibirica (20.41%), and Rickettsia helvetica (2.04%) in the positive samples. The results showed a significant association between county variables and the following variables: tick spp. (p < 0.001), Rickettsia genus infection in ticks (p < 0.001) and Rickettsia spp. (p < 0.001). In addition, there was a significant association between tick species and host animals (dogs and domestic animals) (p < 0.001), Rickettsia spp infection in ticks (p < 0.001), and Rickettsia spp. (p < 0.001). This study indicates a high prevalence of Rickettsia spp. (SFG) in ticks of domestic animals and dogs in rural areas of Kerman Province. The health system should be informed of the possibility of rickettsiosis and the circulating species of Rickettsia in these areas.


Subject(s)
Rickettsia , Animals , Rickettsia/isolation & purification , Rickettsia/genetics , Rickettsia/classification , Iran/epidemiology , Dogs , Dog Diseases/microbiology , Dog Diseases/epidemiology , Phylogeny , Ixodidae/microbiology , Cattle , Sheep , Horses , Cats , Female , Goats , Male , Cattle Diseases/microbiology , Cattle Diseases/epidemiology , Tick Infestations/veterinary , Tick Infestations/epidemiology , Rickettsia Infections/veterinary , Rickettsia Infections/epidemiology , Rickettsia Infections/microbiology , Animals, Domestic , Sheep Diseases/microbiology , Sheep Diseases/epidemiology , Sheep, Domestic
6.
Med Vet Entomol ; 38(1): 99-107, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37715613

ABSTRACT

Ticks are not only bloodsucking ectoparasites but also important vectors of tick-borne diseases (TBDs), posing significant threats to public and animal health. Domesticated animals serve as critical hosts for numerous ticks, highlighting the importance of understanding tick infestations in Taiwan. To address this knowledge gap, we conducted a nationwide survey to identify ticks on domesticated animals and associated environments in 2018 and 2019. A total of 6,205 ticks were collected from 1,337 host animals, revealing the presence of seven tick species, with Rhipicephalus microplus, and Rhipicephalus sanguineus being the dominant species. High infestation rates and widespread distribution of ticks were observed on domesticated animals, especially on dogs and cattle (yellow cattle and angus cattle), and the neighbouring grassland of yellow cattle. While this study has certain limitations, it provides valuable insights into the distribution and prevalence of ticks on domesticated animals in Taiwan and their implications for controlling TBDs. Further research is needed to comprehensively understand the complex interactions among ticks, hosts and pathogens.


Subject(s)
Cattle Diseases , Dog Diseases , Rhipicephalus , Tick Infestations , Tick-Borne Diseases , Animals , Cattle , Dogs , Animals, Domestic , Taiwan/epidemiology , Public Health , Tick Infestations/epidemiology , Tick Infestations/veterinary , Tick Infestations/parasitology , Tick-Borne Diseases/veterinary , Cattle Diseases/epidemiology , Cattle Diseases/parasitology , Dog Diseases/parasitology
7.
Parasitol Res ; 123(6): 254, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38922478

ABSTRACT

The Americas hold the greatest bird diversity worldwide. Likewise, ectoparasite diversity is remarkable, including ticks of the Argasidae and Ixodidae families - commonly associated with birds. Considering that ticks have potential health implications for humans, animals, and ecosystems, we conducted a systematic review to evaluate the effects of bioclimatic, geographic variables, and bird species richness on tick infestation on wild birds across the Americas. We identified 72 articles that met our inclusion criteria and provided data on tick prevalence in wild birds. Using Generalized Additive Models, we assessed the effect of environmental factors, such as habitat type, climatic conditions, bird species richness, and geographic location, on tick infestation. Our findings show that most bird infestation case studies involved immature ticks, such as larvae or nymphs, while adult ticks represented only 13% of case studies. We found birds infested by ticks of the genera Amblyomma (68%), Ixodes (22%), Haemaphysalis (5%), Dermacentor (1%), and Rhipicephalus (0.8%) in twelve countries across the Americas. Our findings revealed that temperature variation and bird species richness were negatively associated with tick infestation, which also varied with geographic location, increasing in mid-latitudes but declining in extreme latitudes. Our results highlight the importance of understanding how environmental and bird community factors influence tick infestation in wild birds across the Americas and the dynamics of tick-borne diseases and their impact on biodiversity.


Subject(s)
Bird Diseases , Birds , Tick Infestations , Animals , Tick Infestations/veterinary , Tick Infestations/epidemiology , Tick Infestations/parasitology , Birds/parasitology , Americas/epidemiology , Bird Diseases/parasitology , Bird Diseases/epidemiology , Animals, Wild/parasitology , Ecosystem , Ticks/physiology , Ticks/classification , Biodiversity , Environment , Prevalence
8.
Exp Appl Acarol ; 92(2): 253-261, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38351235

ABSTRACT

Ticks are competent vectors of a wide range of pathogens. They are of veterinary and public health importance as they affect both animal and human health. Transhumance and the transboundary movements of cattle within the West African Sub-region have facilitated the spread of ticks which threatens the introduction of invasive species. Currently, Rhipicephalus microplus have been identified in the Upper East Region of Ghana which could mean a wider distribution of the species across the country due to livestock trade. This study focused on three sites in the Greater Accra Region, which serves as the gateway to receiving most of the cattle transported from the northern regions of Ghana. Ticks were sampled from August 2022 in the wet season to January 2023 in the dry season. Three tick genera were identified: Amblyomma (19.5%), Hyalomma (1.1%), and Rhipicephalus (79.3%) from the 1,489 feeding ticks collected from cattle. Furthermore, Rhipicephalus microplus, Hyalomma rufipes and Amblyomma variegatum were identified molecularly using primers that target the mitochondrial COI gene. There was a significant association between the tick species and seasons (p < 0.001). Finding R. microplus in this study indicates the extent of the spread of this invasive tick species in Ghana and highlights the need for efficient surveillance systems and control measures within the country.


Subject(s)
Cattle Diseases , Ixodidae , Rhipicephalus , Tick Infestations , Humans , Cattle , Animals , Rhipicephalus/genetics , Tick Infestations/epidemiology , Tick Infestations/veterinary , Ghana , Cattle Diseases/epidemiology , Ixodidae/genetics , Introduced Species
9.
Exp Appl Acarol ; 93(1): 17-33, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38656471

ABSTRACT

Application of chemical acaricides in the control of ticks has led to the problem of tick-acaricide control failure. To obtain an understanding of the possible risk factors involved in this tick-acaricide control failure, this study investigated tick control practices on communal farms in the north-eastern part of the Eastern Cape Province (ECP) of South Africa. A semi-structured questionnaire designed to document specific farm attributes and acaricide usage practices was administered at 94 communal farms from the Oliver Tambo District municipality of the ECP. Data collected indicated that the main acaricide chemicals used at plunge dips of inland and coastal areas were synthetic pyrethroid formulations. Most (75%) farmers claimed not to have noticed a significant reduction in numbers of actively feeding and growing ticks on cattle after several acaricide treatments. Based on the farmers' perceptions, leading factors that could have led to tick-acaricide control failure included: weak strength of the dip solution (76%); poor structural state of dip tanks (42%); and irregular tick control (21%). The rearing of crossbreeds of local and exotic cattle breeds, perceived weak strength of the dip solution and high frequency of acaricide treatment, were statistically associated with proportions of farms reporting tick-acaricide control failure. Furthermore, approximately 50% of farms reported at least four tick control malpractices, which could have resulted in the emergence and spread of tick-acaricide control failure. Other sub-optimal tick control practices encountered included incorrect acaricide rotation, and failure to treat all cattle in a herd. This data will inform and guide the development of management strategies for tick-acaricide control failure and resistance in communal farming areas.


Subject(s)
Acaricides , Cattle Diseases , Tick Control , Tick Infestations , South Africa , Animals , Cattle , Cattle Diseases/prevention & control , Cattle Diseases/parasitology , Cattle Diseases/epidemiology , Tick Infestations/veterinary , Tick Infestations/prevention & control , Tick Infestations/epidemiology , Tick Infestations/parasitology , Risk Factors , Pyrethrins , Ticks/physiology
10.
Exp Appl Acarol ; 92(4): 835-850, 2024 May.
Article in English | MEDLINE | ID: mdl-38578579

ABSTRACT

Ticks are important disease vectors affecting animal health and causing substantial economic loss, especially in the tropics and subtropics. To examine the tick burden of cattle and associated risk factors for tick infestation, ticks were collected from 388 cattle within five regions in Ghana. Most of the cattle were males (50.3%) and generally older than 3 years (65%). Of the animals sampled, 2187 ticks were collected with a mean tick burden of 5.6 ticks per cattle, and the average tick burden on the udder/scrotum being significantly higher than in the anal region (Generalized Linear Mix Model [GLMM], p = 0.01197). The tick species identified were predominantly Amblyomma variegatum (42.6%) and Hyalomma rufipes (26.2%). High proportions of cattle examined were found to have A. variegatum infesting the udder/scrotum. Furthermore, H. rufipes infested mostly the anal region compared to other examined body parts (OR 14.8, 95% CI 8.6-25.4, p < 0.001). Using the GLMM, tick abundance was found to be significantly higher in cattle older than 3 years. The tick burden in the udder/scrotum was higher than that from the chest and leg/thigh of the cattle (GLMM, p < 0.05). The tick burden at the anal region was also significantly higher than the leg/thigh and chest. This study indicates that the preferred attachment sites of ticks on cattle are species-dependent and effective treatment with acaricides should take into consideration the udder/scrotum and anal regions as well as prioritizing older cattle.


Subject(s)
Cattle Diseases , Ixodidae , Tick Infestations , Animals , Cattle , Ghana , Tick Infestations/veterinary , Tick Infestations/epidemiology , Tick Infestations/parasitology , Cattle Diseases/parasitology , Cattle Diseases/epidemiology , Male , Female , Ixodidae/physiology , Ixodidae/growth & development , Risk Factors , Feeding Behavior
11.
Exp Appl Acarol ; 92(3): 439-462, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38388882

ABSTRACT

In Ecuador, the main tick species affecting cattle are Rhipicephalus microplus and Amblyomma cajennense sensu lato. Understanding their spatial distribution is crucial. To assess their distribution, data from 2895 farms visited between 2012 and 2017 were utilized. Ticks were collected during animal inspections, with each farm's location georeferenced. Bioclimatic variables and vapor pressure deficit data were obtained from Climatologies at High resolution for the Earth´s Land Surface Areas (CHELSA) dataset. They were overlaid to develop predictive maps for each species using Random Forest (RF) models. The cross-validation results for RF prediction models showed high accuracy for both R. microplus and A. cajennense s.l. presence with values of accuracy = 0.97 and 0.98, sensitivity = 0.96 and 0.99, and specificity = 0.96 and 0.93, respectively. A carefully selected subset of bioclimatic variables was used to describe the presence of each tick species. Higher levels of precipitation had positive effect on the presence of R. microplus but a negative effect on A. cajennense s.l. In contrast, isothermality (BIO3) was more important for the presence of A. cajennense s.l. compared to R. microplus. As a result, R. microplus had a broader distribution across the country, while A. cajennense s.l. was mainly found in coastal areas with evident seasonality. The coexistence of both species in some regions could be attributed to transitional zones, whereas high altitudes limited tick presence. This information can aid in developing appropriate tick management plans, particularly considering A. cajennense s.l.'s broad host range species and R. microplus's specificity for cattle. Moreover, the predictive models can identify areas at risk of associated challenging hemoparasite, requiring special attention and mitigation measures.


Subject(s)
Amblyomma , Animal Distribution , Cattle Diseases , Climate , Rhipicephalus , Tick Infestations , Animals , Ecuador , Cattle , Rhipicephalus/physiology , Amblyomma/physiology , Amblyomma/growth & development , Tick Infestations/veterinary , Tick Infestations/epidemiology , Tick Infestations/parasitology , Cattle Diseases/parasitology , Cattle Diseases/epidemiology
12.
Exp Appl Acarol ; 93(1): 35-48, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38695989

ABSTRACT

Parasites are typically concentrated on a few host individuals, and identifying the mechanisms underlying aggregated distribution can facilitate a more targeted control of parasites. We investigated the infestation patterns of hard ticks and chigger mites on two rodent species, the striped field mouse, Apodemus agrarius, and the lesser ricefield rat, Rattus losea, in Taiwan. We also explored abiotic and biotic factors that were important in explaining variation in the abundance of ticks and chiggers on rodent hosts. Ticks were more aggregated than chiggers on both rodent species. Factors important for the variation in parasitic loads, especially biotic factors, largely differed between ticks and chiggers. Variation partitioning analyses revealed that a larger proportion of variation in chiggers than in ticks can be explained, especially by abiotic factors. If, as proposed, the higher number of parasites in males is due to a larger range area or immunity being suppressed by testosterone, when A. agrarius males host more ticks, they are expected to also host more chiggers, given that chiggers adopt a similar host finding approach to that of ticks. Instead, the similar abundance of chiggers in male and female A. agrarius implies that a large home range or suppressed immunity does not predispose males to inevitably host more parasites. More variations were explained by abiotic than biotic factors, suggesting that controlling practices are more likely to be successful by focusing on factors related to the environment instead of host traits. Our study indicated that the extent of parasitism is rarely determined by a sole factor, but is an outcome of complex interactions among animal physiology, animal behavior, characteristics of parasites, and the environments.


Subject(s)
Murinae , Rodent Diseases , Tick Infestations , Trombiculidae , Animals , Taiwan , Male , Rats , Female , Murinae/parasitology , Tick Infestations/veterinary , Tick Infestations/parasitology , Tick Infestations/epidemiology , Trombiculidae/physiology , Rodent Diseases/parasitology , Rodent Diseases/epidemiology , Mite Infestations/veterinary , Mite Infestations/parasitology , Mite Infestations/epidemiology , Host-Parasite Interactions , Ixodidae/physiology
13.
Exp Appl Acarol ; 92(3): 463-477, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38361037

ABSTRACT

Ticks are hematophagous arthropods and, during feeding, may transmit pathogens to vertebrate hosts, including humans. This study aimed to investigate the presence of Rickettsia spp. in ticks collected between 2010 and 2013 from free-ranging capybaras (Hydrochoerus hydrochaeris) and opossums (Didelphis albiventris) that inhabit Sabiá Park in Uberlândia, Brazil. Overall, 1,860 ticks were collected: 1,272 (68.4%) from capybaras (487 of the species Amblyomma sculptum, 475 adults and 12 nymphs; 778 Amblyomma dubitatum, 727 adults and 51 nymphs; and seven larva clusters of the genus Amblyomma); and 588 (31.6%) from opossums (21 A. sculptum, one adult and 20 nymphs; 79 A. dubitatum, all nymphs; 15 Ixodes loricatus, 12 adults and three nymphs; 457 Amblyomma sp. larva clusters; 15 Ixodes sp. larva clusters; and one Argasidae larva cluster). Out of 201 DNA samples tested for the presence of Rickettsia spp. DNA using polymerase chain reaction (PCR) 12 showed amplification of a gtlA gene segment that was specific to Rickettsia bellii, a bacterium non-pathogenic to humans. As there has been a report showing serological evidence of infections caused by Rickettsia species of the spotted fever group (SFG) in capybaras and opossums in the park, including Rickettsia rickettsii, the etiological agent of Brazilian spotted fever, and considering the presence of A. sculptum ticks, which are aggressive to humans, as well as these vertebrate hosts, which are amplifiers of R. rickettsii, it is important to monitor the presence of SFG rickettsiae in the Sabiá Park, which is visited daily by thousands of people.


Subject(s)
Didelphis , Ixodidae , Larva , Nymph , Rickettsia , Animals , Brazil , Rickettsia/isolation & purification , Nymph/growth & development , Nymph/microbiology , Nymph/physiology , Larva/microbiology , Larva/growth & development , Larva/physiology , Ixodidae/microbiology , Ixodidae/growth & development , Ixodidae/physiology , Tick Infestations/veterinary , Tick Infestations/parasitology , Tick Infestations/epidemiology , Female , Parks, Recreational , Amblyomma/microbiology , Amblyomma/growth & development , Male , Rodentia/parasitology , Opossums/parasitology
14.
Exp Appl Acarol ; 92(3): 529-546, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38407754

ABSTRACT

This survey sought to molecularly detect Coxiella burnetii in Argasidae and Ixodidae ticks attached to small ruminants in the region of West Azerbaijan (Northwest of Iran) and blood samples collected from the same animals. 451 tick samples and 927 blood samples were obtained from sheep (n = 536) and goats (n = 391) and tested by nested PCR for detection of C. burnetii insertion sequence IS1111 or icd gene sequence. The collected ticks were morphologically classified as Rhipicephalus sanguineus, Rhipicephalus turanicus, Hyalomma asiaticum, Hyalomma anatolicum, or Argas reflexus. 14% of ticks (65 in total 43 for IS1111 and 22 for icd gene) tested positive for C. burnetii, none of which were from the Argas genus. Among the 927 blood samples, 218 (23.5%) tested positive for C. burnetii. The positive result from analysis targeting the genes IS1111 and icd were 131 and 87 respectively. As Q fever is a tickborne zoonosis and endemic to Iran, such information is critical for creating effective, coordinated, and strategic tick and pathogen control programs to prevent disease outbreak in domestic animals and humans.


Subject(s)
Coxiella burnetii , Goat Diseases , Goats , Ixodidae , Q Fever , Sheep Diseases , Animals , Iran/epidemiology , Coxiella burnetii/isolation & purification , Coxiella burnetii/genetics , Sheep , Goat Diseases/epidemiology , Goat Diseases/microbiology , Goat Diseases/parasitology , Sheep Diseases/epidemiology , Sheep Diseases/microbiology , Sheep Diseases/parasitology , Ixodidae/microbiology , Q Fever/veterinary , Q Fever/epidemiology , Tick Infestations/veterinary , Tick Infestations/epidemiology , Argasidae/microbiology , Female , Polymerase Chain Reaction/veterinary , Male
15.
Exp Appl Acarol ; 92(3): 479-506, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38457048

ABSTRACT

Tick-borne pathogens (TBPs) represent a substantial threat to cattle globally, exerting adverse impacts on production, health, and economic viability. This study delves into the prevalence and implications of TTBPs in cattle sourced from resource-limited smallholder livestock farms situated in southeastern Iran, proximate to Afghanistan and Pakistan. Blood and tick specimens were systematically collected from a cohort of 230 cattle, comprising 150 asymptomatic and 80 symptomatic individuals. Genomic DNA isolated from blood samples underwent rigorous examination for the presence of key TBPs, including Anaplasma marginale, A. phagocytophilum, A. bovis, A. centrale, Babesia bigemina, and Theileria annulata, utilizing multiple genetic markers. Nucleotide sequence analysis facilitated the reconstruction of phylogenetic relationships. The study also evaluated various potential risk factors, such as clinical status, gender, age, breed, tick infestation, and management practices, to elucidate their associations with TTBPs. Among the cattle cohort, a staggering 87.8% (202/230) tested positive for at least one pathogen. Prevalence statistics encompassed A. marginale (72.2%), T. annulata (68.3%), A. phagocytophilum/A. platys-like complex (66.1%), A. centrale (16.7%), B. bigemina (10.0%), and A. bovis (6.1%). Remarkably, mixed infections involving two, three, and four pathogens were detected in 23%, 52.1%, and 2.2% of animals, respectively. Notably, all asymptomatic cattle were positive for at least one TBP. Tick infestation was observed in 62.2% (143/230) of cattle, predominantly caused by Hyalomma anatolicum (82.5%), Rhipicephalus (Boophilus) annulatus (13.1%), and R. sanguineus sensu lato (4.4%). Risk factors linked to TBPs encompassed tick infestation, older age, and crossbred animals. Clinical presentations among symptomatic cattle encompassed fever, anemia, weight loss, anorexia, jaundice, and enlarged superficial lymph nodes. This study underscores the pivotal role of asymptomatic carriers in the propagation of TTBPs within endemic regions. Furthermore, it emphasizes the potential for the implementation of molecular diagnostics to unmask subclinical infections, thereby affording the opportunity for targeted interventions aimed at ameliorating the burden of TTBPs in resource-constrained smallholder dairy farms.


Subject(s)
Cattle Diseases , Phylogeny , Animals , Cattle , Iran/epidemiology , Cattle Diseases/epidemiology , Cattle Diseases/parasitology , Female , Male , Risk Factors , Tick-Borne Diseases/veterinary , Tick-Borne Diseases/epidemiology , Tick-Borne Diseases/microbiology , Tick-Borne Diseases/parasitology , Babesia/isolation & purification , Babesia/genetics , Prevalence , Anaplasmosis/epidemiology , Anaplasmosis/microbiology , Theileriasis/epidemiology , Theileriasis/parasitology , Babesiosis/epidemiology , Tick Infestations/veterinary , Tick Infestations/epidemiology , Tick Infestations/parasitology
16.
Can Vet J ; 65(6): 569-573, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38827591

ABSTRACT

Objective: The present study was designed to identify tick species and determine prevalence of Borrelia burgdorferi infection in ticks obtained from companion animals in British Columbia. Animals and samples: Ticks were submitted by British Columbia veterinarians from client-owned companion animals over a 31-month period. Procedure: Each tick was identified and PCR testing for B. burgdorferi undertaken on all Ixodes species identified by the Zoonotic Diseases and Emerging Pathogens Section of British Columbia Centre for Disease Control Public Health Laboratory (BCCDC PHL). Results: Overall, 85% (n = 300) of ticks submitted were Ixodes spp., with the majority known to transmit B. burgdorferi. Furthermore, 0.8% (95% confidence interval: 0.094 to 2.78%) of these ticks were PCR-positive for B. burgdorferi. Conclusion and clinical relevance: Although the B. burgdorferi positivity rate in this study was low, it remains important for veterinary professionals to inform pet owners that ticks are present and can pose a risk to pets and humans. In eastern North America, B. burgdorferi infection risk has increased rapidly, underscoring the importance of ongoing surveillance in British Columbia to understand current and future distributions of ticks and tick-borne pathogens, especially in the context of climate change.


Surveillance passive des tiques et détection de Borrelia burgdorferi chez des tiques provenant d'animaux de compagnie en Colombie-Britannique: 2018 à 2020. Objectif: Cette étude a été élaboré afin d'identifier les espèces de tiques et de déterminer la prévalence de l'infection à Borrelia burgdorferi chez des tiques obtenues d'animaux de compagnie en Colombie-Britannique. Animaux et échantillons: Les tiques ont été soumises par des médecins vétérinaires de la Colombie-Britannique obtenues d'animaux de compagnie de clients sur une période de 31 mois. Procédure: Chaque tique a été identifiée et un test PCR pour détecter B. burdorferi réalisé sur toutes les espèces Ixodes identifiées par la Section des maladies zoonotiques et des agents pathogènes émergents du Centre for Disease Control Public Health Laboratory de la Colombie-Britannique. Résultats: Au total, 85 % (n = 300) des tiques soumises étaient des Ixodes spp., dont la majorité reconnue pour transmettre B. burgdorferi. De plus, 0,8 % (intervalle de confiance 95 %: 0,094 à 2,78 %) de ces tiques étaient positives pour B. burgdorferi par PCR. Conclusion et signification clinique: Bien que le taux de positivité pour B. burgdorferi dans la présente étude soit faible, il n'en demeure pas moins important pour les professionnels vétérinaires d'informer les propriétaires d'animaux de compagnie que les tiques sont présentes et peuvent représenter un risque pour les animaux de compagnie et les humains. Dans le nord de l'Amérique du Nord, le risque d'infection par B. burgdorferi a augmenté rapidement, soulignant l'importance d'une surveillance continue en Colombie-Britannique pour comprendre la distribution actuelle et future des tiques et agents pathogènes transmis par les tiques, spécialement dans le contexte des changements climatiques.(Traduit par Dr Serge Messier).


Subject(s)
Borrelia burgdorferi , Ixodes , Lyme Disease , Pets , Animals , British Columbia/epidemiology , Borrelia burgdorferi/isolation & purification , Lyme Disease/veterinary , Lyme Disease/epidemiology , Ixodes/microbiology , Dogs , Dog Diseases/epidemiology , Dog Diseases/microbiology , Cats , Cat Diseases/epidemiology , Cat Diseases/microbiology , Tick Infestations/veterinary , Tick Infestations/epidemiology , Female , Prevalence , Male
17.
Trop Anim Health Prod ; 56(2): 73, 2024 Feb 10.
Article in English | MEDLINE | ID: mdl-38336895

ABSTRACT

A survey of Ixodid tick species diversity on domestic ruminants was conducted in seven agro-climatic regions of Tamil Nadu State, India. Tick surveys were conducted on domestic ruminants such as cattle, buffalo, sheep, and goat in seven districts of Tamil Nadu. The overall tick infestation was 38.8%, 5.8%, 14.6%, and 40.8% on cattle, buffaloes, sheep, and goats, respectively. A total of 8068 ticks from 18 species belonging to four genera were recorded. Overall, Haemaphysalis intermedia was the predominant (51.38%) tick species which has a wide host range. The most prevalent tick species in cattle and buffalo were Rhipicephalus (B.) microplus (25.41%) and Rhipicephalus haemaphysaloides (56.69%), respectively. Haemaphysalis intermedia was the most prevalent in ticks in sheep (70.35%), goat (70.35%), and dog (55.79%). In the present study, local anomalies such as the ectromely of one leg and the absence of adanal plates were observed in Rh. haemaphysaloides. The study also found that local anomaly such as protuberances in the hind tarsal and atrophy of the adanal plate was observed in Rhipicephalus (Boophilus) microplus. In addition, a general anomaly with three atrophy caudal appendages was also observed in Rhipicephalus (Boophilus) microplus. The overall prevalence of anomalies in Rh. haemaphysaloides and Rh. (B.) microplus was 0.3% (3/971) and 0.4% (3/678), respectively.


Subject(s)
Bison , Cattle Diseases , Dog Diseases , Goat Diseases , Ixodidae , Rhipicephalus , Sheep Diseases , Tick Infestations , Cattle , Animals , Sheep , Dogs , Buffaloes , India/epidemiology , Tick Infestations/epidemiology , Tick Infestations/veterinary , Goats , Atrophy/veterinary , Cattle Diseases/epidemiology , Goat Diseases/epidemiology , Sheep Diseases/epidemiology
18.
Ecol Lett ; 26(12): 2029-2042, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37882483

ABSTRACT

Although the role of host movement in shaping infectious disease dynamics is widely acknowledged, methodological separation between animal movement and disease ecology has prevented researchers from leveraging empirical insights from movement data to advance landscape scale understanding of infectious disease risk. To address this knowledge gap, we examine how movement behaviour and resource utilization by white-tailed deer (Odocoileus virginianus) determines blacklegged tick (Ixodes scapularis) distribution, which depend on deer for dispersal in a highly fragmented New York City borough. Multi-scale hierarchical resource selection analysis and movement modelling provide insight into how deer's movements contribute to the risk landscape for human exposure to the Lyme disease vector-I. scapularis. We find deer select highly vegetated and accessible residential properties which support blacklegged tick survival. We conclude the distribution of tick-borne disease risk results from the individual resource selection by deer across spatial scales in response to habitat fragmentation and anthropogenic disturbances.


Subject(s)
Communicable Diseases , Deer , Ixodes , Tick Infestations , Humans , Animals , Animals, Wild , New York City , Tick Infestations/epidemiology , Tick Infestations/veterinary , Ixodes/physiology
19.
Oecologia ; 203(3-4): 421-433, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37955713

ABSTRACT

Heterogeneous aggregation of parasites between individual hosts is common and regarded as an important factor in understanding transmission dynamics of vector-borne diseases. Lyme disease is vectored by generalist tick species, yet we have a limited understanding of how individual heterogeneities within small mammal host populations affect the aggregation of ticks and likelihood of infection. Male hosts often have higher parasite and infection levels than females, but whether this is linked to sexual body size dimorphism remains uncertain. Here, we analysed how host species, sex, and body mass influenced Ixodes ricinus tick infestations and the infection prevalence of Borrelia burgdorferi sensu lato (s.l.) in three species of small mammals involved in the enzootic transmission cycle of Lyme disease in Norway from 2018 to 2022. Larval and nymphal ticks were found on 98% and 34% of all individual hosts, respectively. In bank voles and wood mice, both larval and nymphal tick infestation and infection probability increased with body mass, and it increased more with mass for males than for females. Tick infestation in the common shrew increased with body mass and was higher in males, while pathogen infection was higher in females. Sex-biases in infestation did not correspond with level of sexual body mass dimorphism across species. This study contributes to our understanding of how individual heterogeneity among small mammalian hosts influences I. ricinus tick aggregation and prevalence of B. burgdorferi s.l. at northern latitudes.


Subject(s)
Borrelia burgdorferi , Ixodes , Lyme Disease , Parasites , Tick Infestations , Female , Animals , Male , Mice , Tick Infestations/epidemiology , Tick Infestations/veterinary , Tick Infestations/parasitology , Prevalence , Lyme Disease/epidemiology , Lyme Disease/veterinary , Mammals , Nymph , Larva
20.
BMC Vet Res ; 19(1): 121, 2023 Aug 12.
Article in English | MEDLINE | ID: mdl-37573333

ABSTRACT

BACKGROUND: Hard ticks infesting cattle are vectors of Tick-borne diseases that causes major public health problems and considerable socioeconomic losses to the livestock industry in tropical and subtropical countries. A repeated cross-sectional study was carried out by collecting ticks on cattle during the wet and dry seasons from January to August 2021 in order to determine hard tick prevalence, distribution, and abundance on cattle in Kilombero and Iringa Districts of Tanzania. The collected ticks were identified morphologically using published morphological keys under a stereomicroscope and confirmed by polymerase chain reaction (PCR) and sequencing. RESULTS: Out of 740 examined cattle, 304, (41.08%) were infested with ticks. In total, 1,780 ticks were counted on one side of the animal's body and doubled, whereby resulting in a total of 3,560 ticks were recorded. Individual tick burden ranged from n = 2 to 82 ticks per animal, with a mean tick burden of n = 11.7 ± 0.68 per animal. A total of 1,889 ticks were collected from infected cattle including 109 additional ticks observed while collecting ticks based on the animal's posture when restrained to the ground. Out of 1,889 ticks, nine species from three genera were identified morphologically: 1,377 fit in the genus Rhipicephalus, 459 to the genus of Amblyomma, and 53 to the genus Hyalomma. Rhipicephalus microplus was the most prevalent (n = 909, 48.1%), followed by Rhipicephalus evertsi (n = 310, 16.4%), Amblyomma lepidum (n = 310, 16.4%), Rhipicephalus appendiculatus (n = 140, 7.4%), Amblyomma gemma (n = 120, 6.4%), Hyalomma rufipes (n = 50, 2.6%), Amblyomma variegatum (n = 29, 1.5%), Rhipicephalus decoloratus (n = 18, 1.0%), while the least common was Hyalomma albiparmatum (n = 3, 0.2%). Tick diversity was higher in Iringa compared to Kilombero District. Tick prevalence was higher in wet season (n = 148, 41.11%). Ticks were widely distributed in different parts of the host body, with the highest distribution on zone 4 (n = 1,060, 56.11%), which includes groin, flank, abdomen, and around inner thigh of the hind legs and the lowest distribution on zone 2 (n = 14, 0.74%), which includes the back surface of the body. Both Amblyomma lepidum and Rhipicephalus microplus species were found in all the five body zones, and with the highest proportions recorded on zone 4: A. lepidum (n = 209, 67.42%) and R. microplus (n = 714, 78.55%). The nine tick species identified morphologically were also confirmed using molecular methods. However, during sequencing, two species (Rhipicephalus appendiculatus and R. decoloratus) had poor quality sequences and were excluded from the sequence analysis. Sequencing results indicated high nucleotide identity (96-100%) with sequences available in GenBank and Barcode of Life Database (BOLD). The phylogenetic analysis of partial mitochondrial COI and 16S rRNA gene sequences of ticks were used to confirm the morphological identification. CONCLUSION: The results showed a high burden of tick infestation on cattle, which could reduce animal production and potentially increase the risk of tick-borne diseases. Therefore, it is necessary to explore the epidemiological and molecular aspects of various tick species in other regions of Tanzania.


Subject(s)
Cattle Diseases , Ixodidae , Rhipicephalus , Tick Infestations , Tick-Borne Diseases , Animals , Cattle , RNA, Ribosomal, 16S , Tanzania/epidemiology , Cross-Sectional Studies , Phylogeny , Cattle Diseases/epidemiology , Tick Infestations/epidemiology , Tick Infestations/veterinary , Amblyomma , Tick-Borne Diseases/epidemiology , Tick-Borne Diseases/veterinary
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