Survey of tick species parasiting domestic ruminants in Ghaemshahr county,Mazandaran province,Iran

ObjectiveTo determine the tick species parasitizing domestic ruminants in Ghaemshahr county in Mazandaran, a Caspian province in the north of Iran.MethodsAbout 361 sheep, 54 goats and 10 cattle of 18 herds in several villages in Ghaemshahr were inspected for tick infestation. Separated ticks were preserved in 70% alcohol and identified.ResultsAbout 323 ticks (207 female, 116 male) were collected, the occurrence of ticks on sheep, goats and cattle were 28.3%, 22.2% and 20.0% respectively. The mean number of ticks on each animal was low (3-5 ticks per animal). Rhipicephalus sanguineus, Rhipicephalus bursa, Ixodes ricinus, Boophilus annulatus, Haemaphysalis punctata and Haemaphysalis numidiana were the tick species we found. Rhipicephalus sanguineus were the most abundant species in the study area. The largest number of ticks were generally present from April to July, mostly in animal ears and tails. Ixodes, Boophilus and Haemaphysalis occurred in mountainous areas of Ghaemshahr, whereas Rhipicephalus were present in both mountains and plains of the study area.ConclusionsThe result of this study is a survey of tick species from domestic animals in Iran and implication of possible prevention measures for diseases transmitted by ticks.     

First molecular detection of Theileria ovis in Rhipicephalus sanguineus tick in Iran

ObjectiveTo determine tick infestation of domestic ruminants and their infection to ovine theileriosis in northern Iran.MethodsAbout 425 domestic ruminants in Ghaemshahr city in northern Iran were inspected for tick infestations. Twenty tick specimens (13 females and 7 males) of Rhipicephalus sanguineus (R. sanguineus), the most common tick in the study area, were tested by PCR amplification against 18s rRNA genome of Theileria spp using specie specific primers and then the PCR products were sequenced for species identification by comparison with data base available in GenBank.ResultsAbout 323 ticks were collected from 102 animals (88 sheep, 12 goats and 2 cattle). The prevalence of ticks infesting animals was R. sanguineus (82.35%), Rhipicephalus bursa (R. bursa) (0.3%), Ixodes ricinus (I. ricinus) (15.2%), Boophilus annulatus (B. annulatus) (1.2%), Haemaphysalis punctata (H. punctata) (0.3%) and Haemaphysalis numidiana (H. numidiana) (0.6%). Eleven (55%) tick specimens were PCR positive against genome of Theileria ovis (T. ovis). Sequence analysis of the PCR products confirmed presence of T. ovis in one R. sanguinus.ConclusionsThis is the first report of tick infection to T. ovis in Iran. Due to dominant prevalence of R. sanguineus as well as its infection to T. ovis, it is postulated this tick is the main vector of ovine theileriosis in northern Iran.     

Characterising African tick communities at a wild–domestic interface using repeated sampling protocols and models

The sharing of habitat by wild and domestic animals may result in pathogen transmission, notably via ectoparasite vectors such as ticks. Interfaces between protected and communal lands constitute sharp transitions between areas occupied by host communities that are extremely contrasted in terms of composition, diversity and density. Empirical characterizations of tick communities and of their vertebrate hosts are strongly relevant for understanding the mechanisms leading to disease transmission between wild and domestic animals. In the present study we aimed at depicting the pattern of spatial variation in the density of immature ticks at such an interface located in Zimbabwe. At the end of the 2011 rainy season, we applied a hierarchical repeated protocol to collect ticks. We used the drag-sampling method in the vegetation surrounding water pans used by ungulates in 3 distinct landscape compartments (i.e. national park, mixed compartment and communal lands) characterized by a differential use by wild and domestic hosts. We combined generalized linear mixed models with site occupancy models to (1) assess tick aggregation levels at different spatial scales, (2) identify and disentangle factors which influence the density and probability of tick detection, and (3) compare robust estimations of tick densities among the landscape compartments. Ticks belonging to the Amblyomma and Riphicephalus genuses were found to be the most abundant. At small scale, ticks were more often detected in the afternoon and were more abundant close to water pans for Amblyomma and Riphicephalus genuses. Riphicephalus spp. density was also higher in grassland and bushland vegetation types as compared to woodland vegetation type. At large scale, for the three detected genuses, density was much higher near water pans located in the communal lands as compared to the national park and mixed compartment. Given that host community's diversity is much lower in the communal areas than in the two other landscape compartments, these results are compatible with a dilution effect but not sufficient to demonstrate this effect without additional studies. Up to date, it is the first utilization of these rigorous sampling and statistical modelling methodologies to estimate tick density in African ecosystem simultaneously at large and small scales.     

Ectoparasites and gastrointestinal parasites of nomadic cattle infiltrating into Kainji Lake National Park Nigeria

The examination of 317 nomadic cattle infiltrating into the Kainji Lake National Park revealed seven tick species, Ambylomma variegatum, Boophilus decolaratus, B. annulatus, Hylomma aegyptium, Rhipicephalus appendiculata?, R. everti, R. simus senegalensis, one mite Demodex bovis and a lice species Damalina bovis. These ectoparasites have the ability of attaching to wild animals of the park in particular the two host and three host tick species Hylomma sp., Rhipicephalus spp. and Ambylomma sp. The endoparasites include nine nematodes species, five trematodes and eimeria sp. The occurrence of these endoparasites is an indication of the risk of cross-infection because similar helminth fauna have been reported in wild animals of the park. It is concluded that the need to prevent entry of cattle into the park should be encouraged because of the pasture contamination and potential risk of cross parasitic infection between the domestic cattle and wild animals of the park.     

Prevalence of Human-Active and Variant 1 Strains of the Tick-Borne Pathogen Anaplasma phagocytophilum in Hosts and Forests of Eastern North America

Anaplasmosis is an emerging infectious disease caused by infection with the bacterium Anaplasma phagocytophilum. In the eastern United States, A. phagocytophilum is transmitted to hosts through the bite of the blacklegged tick, Ixodes scapularis. We determined the realized reservoir competence of 14 species of common vertebrate hosts for ticks by establishing the probability that each species transmits two important strains of A. phagocytophilum (A. phagocytophilum human-active, which causes human cases, and A. phagocytophilum variant 1, which does not) to feeding larval ticks. We also sampled questing nymphal ticks from ∼150 sites in a single county over 2 years and sampled over 6 years at one location. White-footed mice (Peromyscus leucopus) and Eastern chipmunks (Tamias striatus) were the most competent reservoirs for infection with the A. phagocytophilum human-active strain. Across the county, prevalence in ticks for both strains together was 8.3%; ticks were more than two times as likely to be infected with A. phagocytophilum human-active as A. phagocytophilum variant 1.     

Crimean-congo hemorrhagic fever in South Africa

Crimean-Congo hemorrhagic fever virus was isolated for the first time in South Africa in February 1981, from the blood of a 13-year-old boy who died in Johannesburg after attending a camp in a nature reserve in the western Transvaal. Virus was isolated from 21/120 pools of questing ticks from the nature reserve, the infected species being Hyalomma marginatum rufipes and H. truncatum. Virus was also isolated from 4/38 pools of partially engorged ticks and other ectoparasites collected off hosts, the infected species being H.m. rufipes, H. truncatum and Rhipicephalus evertsi. Antibodies were found in the sera of 5/74 humans, 8/26 wild vertebrates, 74/270 sheep, and 109/170 cattle from the reserve and surrounding farms. Antibodies were also found in 28/200 hares from various locations in the country. It was concluded that the virus is widely prevalent in South Africa, but the full medical and veterinary significance of its presence has yet to be determined.     

Coincident Tick Infestations in the Nostrils of Wild Chimpanzees and a Human in Uganda

Ticks in the nostrils of humans visiting equatorial African forests have been reported sporadically for decades, but their taxonomy and natural history have remained obscure. We report human infestation with a nostril tick in Kibale National Park, Uganda, coincident with infestation of chimpanzees in the same location with nostril ticks, as shown by high-resolution digital photography. The human-derived nostril tick was identified morphologically and genetically as a nymph of the genus Amblyomma, but the mitochondrial 12S ribosomal RNA or the nuclear intergenic transcribed spacer 2 DNA sequences of the specimen were not represented in GenBank. These ticks may represent a previously uncharacterized species that is adapted to infesting chimpanzee nostrils as a defense against grooming. Ticks that feed upon apes and humans may facilitate cross-species transmission of pathogens, and the risk of exposure is likely elevated for persons who frequent ape habitats.     

Factors influencing the distribution of larval blacklegged ticks on rodent hosts

Because of differences among hosts in reservoir competence for tick-borne diseases, the distribution of larval blacklegged ticks on hosts might determine tick infection prevalence and disease risk to humans. We conducted a three-part study to determine the factors responsible for greater burdens of larval blacklegged ticks on white-footed mice than on eastern chipmunks. A microhabitat study indicated that questing ticks have higher encounter rates with mice than with chipmunks. Laboratory experiments demonstrated that ticks oriented more strongly toward mice. However, larval ticks fed more successfully from chipmunks. Our results strongly suggest that mice are both more likely to use larval tick-infested microhabitats and to attract questing larvae than are chipmunks, leading to a dramatically higher initial infestation rate, which is then reduced by greater grooming activity by mice. The high mortality rate of larvae that were experimentally introduced onto mice suggests that grooming is a significant cause of mortality to larval blacklegged ticks.     

NEW WILDLIFE HOSTS OF Leptospira interrogans IN CAMPECHE,MEXICO

Leptospira interrogans has been identified to cause leptospirosis, a widespread zoonotic disease that has been identified in domestic and wild animals. This work analyzed kidneys from two species of wild rodents from the state of Campeche, Mexico. Analyses were made by PCR using specific primers for detection of Leptospira interrogans DNA. The rodent species that tested positive were Heteromys gaumeri and Ototylomys phyllotis, both of which are new hosts for the bacteria in Southeastern Mexico. These records provide new insights into the disease’s transmission that should be studied carefully in order to identify other potential host species, including humans, which are at risk of becoming infected if they are in contact with infected wildlife.     

Seasonality of Ixodes ricinus ticks on vegetation and on rodents and Borrelia burgdorferi sensu lato genospecies diversity in two lyme borreliosis-endemic areas in Switzerland

We compared Ixodes ricinus questing density, the infestation of rodents by immature stages, and the diversity of Borrelia burgdorferi sensu lato (sl) in questing ticks and ticks collected from rodents in two Lyme borreliosis (LB)-endemic areas in Switzerland (Portes-Rouges [PR] and Staatswald [SW]) from 2003 to 2005. There were variations in the seasonal pattern of questing tick densities among years. Questing nymphs were globally more abundant at PR than at SW, but the proportion of rodents infested by immature ticks was similar (59.4% and 61%, respectively). Questing tick activity lasted from February to November with a strong decline in June. The seasonal pattern of ticks infesting rodents was different. Ticks infested rodents without decline in summer, suggesting that the risk of being bitten by ticks remains high during the summer. Rodents from SW showed the highest infestation levels (10±21.6 for larvae and 0.54±1.65 for nymphs). The proportion of rodents infested simultaneously by larvae and nymphs (co-feeding ticks) was higher at SW (28%) than at PR (11%). Apodemus flavicollis was the species the most frequently infested by co-feeding ticks, and Myodes glareolus was the most infective rodent species as measured by xenodiagnosis. At PR, the prevalence of B. burgdorferi sl in questing ticks was higher (17.8% for nymphs and 32.4% for adults) than at SW (10.4% for nymphs and 24.8% for adults), with B. afzelii as the dominant species, but B. garinii, B. burgdorferi sensu stricto, and B. valaisiana were also detected. Rodents transmitted only B. afzelii (at PR and at SW) and B. bavariensis (at SW) to ticks, and no mixed infection by additional genospecies was observed in co-feeding ticks. This implies that co-feeding transmission does not contribute to genospecies diversity. However, persistent infections in rodents and co-feeding transmission contribute to the perpetuation of B. afzelii in nature.     

滇西横断山区家畜体表蜱类调查及鉴定

目的 调查滇西横断山区家畜体表蜱的种类。方法 采集家畜体表寄生的蜱虫,经形态学鉴定后,用PCR法扩增蜱虫样本的16S rRNA、12S rRNA、COI、ITS2的基因片断,测序后进行序列分析。结果 共采集成虫蜱样本1 874只,经形态学鉴定为1科、1属(扇头蜱属Rhipicephalus)、4种,其中微小扇头蜱(R. microplus)1 637只(占87.35%)),镰形扇头蜱(R. haemaphysaloides)218只(11.63%),短小扇头蜱(R. pumilio)11只(0.59%),血红扇头蜱(R. sanguineus)8只(0.43%)。样品分子鉴定结果与形态学鉴定结果一致。系统发育树分析显示,微小扇头蜱Y2 16S rRNA、12S rRNA、COI、ITS2的基因序列分别与来自印度(EU918188)、贵州(KC503259)、马来西亚(KM246873)、贵州(KC503274)的微小扇头蜱在同一分支上,而与以往云南发现的微小扇头蜱不在同一分支;镰形扇头蜱Y5的 16S rRNA、12S rRNA和COI基因序列分别与来自泰国(KC170743)、台湾(DQ003005)和湖南(KM083593)的镰形扇头蜱在同一分支上;短小扇头蜱Y6和Y01 的ITS2基因序列与来自澳大利亚的短小扇头蜱(AF271282)在同一分支上。结论 滇西横断山区家畜体表蜱以微小扇头蜱为优势种,短小扇头蜱为云南境内首次发现。     

Ixodid ticks on domestic animals in Samut Prakan Province,Thailand

The prevalence of tick-harboring domestic animals, tick density, and the species of ticks were studied throughout the year 2000, in Muang Samut Prakan, Bang Phli and Phra Pradaeng districts of Samut Prakan Province. The animals examined were Canis lupus familiaris (450), Bos indicus (cross-bred) (189), Bos taurus (30), Bubalus bubalis (171) and Sus scrofa domestica (450). The total number of collected ticks was 1,491. The pigs did not harbor ticks. The stages of ticks collected were larvae, nymphs and adults. The prevalence rates of tick-harboring were 46% (Canis lupus familiaris), 42.86% (Bos indicus, cross-bred), 33.33% (Bos taurus) and 9.35% (Bubalus bubalis). The tick densities were 2.22 (Bos indicus, cross-bred), 2.16 (Canis lupus familiaris), 1.16 (Bos taurus) and 0.36 (Bubalus bubalis). Only 2 species of ixodid ticks, Boophilus microplus and Rhipicephalus sanguineus, were found. R. sanguineus was the dominant species of tick. The percentage of R. sanguineus was 65.2% and B. microplus was 34.8%. In Muang district, R. sanguineus was the dominant species in C. lupus familiaris; in Bang Phli district, B. microplus was the dominant species in Bos indicus (cross-bred). The density of B. microplus was high in the summer season; the density of R. sanguineus was high in the winter season. The number of ticks depended on the geographic location, animal host and season.     

Sympatric Ixodes trianguliceps and Ixodes ricinus ticks feeding on field voles (Microtus agrestis): potential for increased risk of Anaplasma phagocytophilum in the United Kingdom?

The importance of wild rodents as reservoirs of zoonotic tick-borne pathogens is considered low in the United Kingdom because, in studies to date, those parasitized by exophilic Ixodes ricinus ticks carry almost exclusively larvae and thus have a minor role in transmission cycles. In a cross-sectional study, 11 (6.7%) of 163 field voles (Microtus agrestis) captured at field sites in Northern England were PCR-positive for Anaplasma phagocytophilum. The voles were found to act as hosts for both larval and nymphal I. ricinus and all stages of the nidicolous tick I. trianguliceps, and eight individuals were infested with ticks of both species at the same time. Two of 158 larval and one of 13 nymphal I. ricinus, as well as one of 14 larval and one of 15 nymphal I. trianguliceps collected from the rodents were PCR-positive. These findings suggest that habitats where field voles are abundant in the United Kingdom may pose a risk of A. phagocytophilum infection because (i) field voles, the most abundant terrestrial mammal in the United Kingdom, may be a competent reservoir; (ii) the field voles are hosts for both nymphal and larval ixodid ticks so they could support endemic cycles of A. phagocytophilum; and (iii) they are hosts for nidicolous I. trianguliceps, which may alone maintain endemic cycles, and exophilic I. ricinus ticks, which could act as a bridge vector and transmit infections to humans and domesticated animals.     

塔里木盆地三种扇头蜱的鉴别要点

目的 澄清三种扇头蜱的存在,列出3种扇头蜱的鉴别要点.方法 从不同自然景观和家、野生动物体上采集蜱类进行分类鉴定.结果 共获得蜱类18 000余只.经鉴定隶属2科5属10种.结论 其中优势蜱种为璃眼蜱属Hyalomma中的种类.其次是扇头蜱属Rhipicephalus、革蜱属Dermacentor、血蜱属Haemaphysalis和钝缘蜱属Ornithodoros的种类.     

Potential vertebrate reservoir hosts and invertebrate vectors of Anaplasma marginale and A. phagocytophilum in central Spain

Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, A. marginale, causes bovine anaplasmosis and only infects ticks and ruminants. A. phagocytophilum causes human and animal granulocytic anaplasmosis, and genetically closely related strains show a wide host range, including ticks, ruminants, rodents, equids, canids, birds, and humans. Recent reports demonstrated that A. marginale and A. phagocytophilum co-exist in geographic areas and that concurrent infections occur in ruminants and ticks. In this study, we characterized A. marginale and A. phagocytophilum infections in wild and domestic animals, and ticks collected in central Spain by serology, PCR, and sequence of 16S rRNA genotypes. Species tested included humans, cattle, dogs, rodents, Iberian red deer, European wild boar, birds, and ticks. Species of hematophagous Diptera were analyzed as potential mechanical vectors of Anaplasma spp. A. marginale was detected in tabanids, ticks, cattle, and deer, while A. phagocytophilum was detected in ticks, deer, cattle, and birds. Concurrent infections of the two Anaplasma were found in cattle and deer. These results illustrate the complexity of the epizootiology of A. marginale and A. phagocytophilum in regions where both pathogens co-exist and share common reservoir hosts and vectors. The increasing contact between wildlife, domestic animals, and human populations increases the risk of outbreaks of human and bovine anaplasmosis, and the difficulty of implementing surveillance and control measures.     

Occurrence and Genotyping of Coxiella burnetii in Ixodid Ticks in Oromia,Ethiopia

This study was conducted from September 2011 to March 2014 to address the occurrence and genotypes of Coxiella burnetii using molecular methods in ticks collected from domestic animals in Ethiopia. Ticks were tested for C. burnetii by quantitative real-time polymerase chain reaction (qPCR) targeting two different genes followed by multispacer sequence typing (MST). An overall prevalence of 6.4% (54/842) of C. burnetii was recorded. C. burnetii was detected in 28.6% (14/49) of Amblyomma gemma, 25% (31/124) of Rhipicephalus pulchellus, 7.1% (1/14) of Hyalomma marginatum rufipes, 3.2% (2/62) of Am. variegatum, 3.1% (4/128) of Am. cohaerens, 1.6% (1/63) of Rh. praetextatus, and 0.6% (1/153) of Rhipicephalus (Boophilus) decoloratus. Significantly higher overall frequencies of C. burnetii DNA were observed in Am. gemma and Rh. pulchellus than in other tick species (Mantel–Haenszel [MH], P < 0.0001). The overall frequency of C. burnetii was significantly higher (MH, P < 0.0001) in ticks from southeastern districts (Arero, Moyale, and Yabelo) than that from other districts. This study demonstrated the presence of C. burnetii genotype MST 18 in ticks in southeastern districts and genotype MST 20 in ticks in central districts. This study highlights the importance of ticks in the epidemiology of C. burnetii in Ethiopia.     

Evasin‐3‐like anti‐chemokine activity in salivary gland extracts of ixodid ticks during blood‐feeding: a new target for tick control

Ticks exploit many evasion mechanisms to circumvent the immune control of their hosts including subversion of the communication language between cells of the immune system provided by chemokines and other cytokines. One subversive molecule secreted in the saliva of Rhipicephalus sanguineus is Evasin‐3, a structurally unique 7 kDa protein that selectively binds the neutrophil chemoattractants, CXCL8 and (with lower affinity) CXCL1. We compared anti‐human CXCL8 and anti‐mouse CXCL1/KC activities in salivary gland extracts prepared from adult Amblyomma variegatum, Rhipicephalus appendiculatus and Dermacentor reticulatus ticks during blood‐feeding. Both anti‐CXCL8 activity and anti‐CXCL1 activity were detected in all species and in both adult females and males, with consistently higher activity levels against CXCL8. These results suggest that Evasin‐3‐like activity is common amongst metastriate ixodid tick species, and provide further evidence of the importance to ticks in controlling neutrophils during blood‐feeding. As such, Evasin‐3 offers a new target for anti‐tick vaccine development.     

Antischistosomal versus Antiandrogenic Properties of Aryl Hydantoin Ro 13-3978

Rickettsia parkeri, a newly recognized tick-borne pathogen of humans in the Americas, is a confirmed cause of spotted fever group rickettsiosis in Argentina. Until recently, almost all cases of R. parkeri rickettsiosis in Argentina have originated from the Paraná River Delta, where entomological surveys have identified populations of R. parkeri-infected Amblyomma triste ticks. In this report, we describe confirmed cases of R. parkeri rickettsiosis from Córdoba and La Rioja provinces, which are located several hundred kilometers inland, and in a more arid ecological region, where A. triste ticks do not occur. Additionally, we identified questing A. tigrinum ticks naturally infected with R. parkeri in Córdoba province. These data provide evidence that another human-biting tick species serves as a potential vector of R. parkeri in Argentina and possibly, other countries of South America.