Rhipicephalus Sanguineus Group Research Articles

Seasonal Dynamics and Physiological Age of Ixodid Ticks Collected from Dogs.

In order to reproduce and complete life cycles, ticks have to feed on different hosts, thus participating as vectors and reservoirs in the maintenance and circulation of different pathogens. Since dogs can serve as suitable hosts for numerous tick species, the aims of this study were to determine tick species and their seasonal occurrence on pet dogs and to compare the accuracy of three indices frequently used to calculate engorged female physiological age. Ticks were collected from dogs brought to veterinary clinics. Three indices were analyzed: scutal index, alloscutal/scutal index ratio, and physiological age index. Four tick species were identified: Ixodes ricinus, Dermacentor marginatus, D. reticulatus, and Rhipicephalus sanguineus group, and the last was the most abundant. The highest number of collected ticks was in April, but two species were continuously active throughout the year. The statistical analyses distinguished the physiological age index as more precise because of lower variability. Dog owners usually ignore regular dog anti-tick treatments throughout the year, as they are not aware that ticks could be active during the winter months. Tick surveillance is unquestionably important in order to monitor and prevent the distribution of these vectors and also the diseases they transmit.

Reestablishment of Rhipicephalus secundus Feldman-Muhsam, 1952 (Acari: Ixodidae)

Rhipicephalus secundus is reestablished as a valid tick name within the Rhipicephalus sanguineus group and removed from the synonymy list of Rhipicephalus turanicus. Morphological re-description of both male and female of R. secundus and the analysis of its phylogenetic position based on mitochondrial DNA sequences are presented. The morphological re-description was made with tick specimens collected on goat in Israel. The phylogenetic analyses showed that R. secundus belong to a different clade from those formed by R. turanicus sensu stricto (s.s.) and R sanguineus s.s., and by other taxa from the R. sanguineus group. Rhipicephalus secundus is morphologically related to R. turanicus, but the scutal punctation pattern of both male and female allows the morphological differentiation between R. secundus and R. turanicus, punctations being clearly more numerous and larger in the latter. Both male and female of R. secundus can be differentiated from those of R. sanguineus s.s. by the shape of the spiracular plate. In males, the dorsal prolongation of the spiracular plate is equal to the breadth of the adjacent festoon in R. secundus, while it is narrower than the breadth of the adjacent festoon in R. sanguineus s.s. The dorsal prolongation of the spiracular plate in the female of R. secundus is wider than in the female of R. sanguineus s.s. The genital apertures of the females of R. secundus and R. sanguineus are both U-shaped, but in R. sanguineus s.s. it is broader than in R. secundus. Considering the results obtained in this study, it can be stated that R. secundus is present at least in Israel, Palestinian Territories, Turkey, Albania and southern Italy, but it is necessary to carry out additional studies to determine the geographical range and host usage of this species.

Occurrence of Babesia Species and Co-Infection with Hepatozoon canis in Symptomatic Dogs and in Their Ticks in Eastern Romania.

Although the distribution of Babesia spp. and Hepatozoon canis is well known in Romania, there is still a marked lack of information in many places of the country. This study aimed to investigate the occurrence of these haemoparasites in symptomatic dogs and in their ticks in Iasi, eastern Romania. Ninety owned dogs were subjected to clinical examination at the Faculty of Veterinary Medicine of Iasi and all detectable ticks (58 ticks from 15 dogs) were collected. Additionally, 124 ticks collected from the coat of other dogs (no. = 23) were included. Three Babesia species were found in dogs: Babesia canis (94.4%), Babesia vogeli (3.3%), and Babesia rossi (2.2%). All the dogs resulted negative for H. canis. The ticks were identified as follows: Ixodes ricinus (64%), Dermacentor reticulatus (33%), and Rhipicephalus sanguineus group (3%). B. canis (Minimum Infection Rate; MIR = 81%), B. vogeli (MIR = 3%), and Babesia microti-like piroplasm (MIR = 1%) were found in ticks. Moreover, 15 ticks were positive for H. canis, 6 were co-infected with B. canis, and 1 with B. microti-like piroplasm. This is the first molecular identification of B. rossi in two symptomatic dogs from Romania, although further studies are needed to investigate the vector competence of other ticks from Europe.

Rhipicephalus sanguineus Complex in the Americas: Systematic, Genetic Diversity, and Geographic Insights.

The Rhipicephalus sanguineus group encompasses at least 12 validated species of Palearctic and Afrotropical hard ticks, which are relevant in veterinary medicine and public health. The taxonomy of R. sanguineus s.s., has been particularly intensely debated, due to its wide geographic distribution, morphological variants, parasite-host associations, and its capacity and vectorial competence for the transmission of several pathogens. By sequencing mitochondrial markers, it was possible to identify the existence of multiple lineages, among which the Tropical and the Temperate lineages stand out, particularly in America. However, the northern limit between these lineages is not clear due to the lack of extensive sampling across Mexico. For this reason, the aim of the present study was to determine the genetic diversity and structure of the R. sanguineus group in Mexico and to compare it with the populations reported in the Americas, in order to propose the northern limit of the R. sanguineus Tropical lineage and the potential regions of sympatry with R. sanguineus s.s. The findings of this study now confirm the presence of R. sanguineus s.s. in Mexico, showing a subtle genetic structure and high genetic diversity throughout its distribution in the Americas. In contrast, the Tropical lineage seems to be genetically less diverse in its overall distribution in the Americas. The genetic diversity of these two independent lineages could have important epidemiological implications in the transmission of tick pathogens.

Genetic analysis of Rhipicephalus sanguineus sensu lato ticks, parasites of dogs in the Canary Islands, Cyprus, and Croatia, based on mitochondrial 16S rRNA gene sequences.

The aim of this work was to perform an analysis based on mtDNA sequences of the 16S rRNA gene in order to determine the phylogenetic position of ticks belonging to the Rhipicephalus sanguineus group from the Canary Islands, Cyprus, and Croatia. All the haplotypes obtained from ticks collected in the Canary Islands and Croatia grouped with R. sanguineus sensu stricto from France, Portugal, Italy, Switzerland, Argentina, Chile, Uruguay, and the USA. The sequences of R. sanguineus sensu lato from Cyprus formed a clade with R. sanguineus s.l. from Egypt, Turkey, and Romania, which belongs to the "Rhipicephalus sp. morphotype I" or "southeastern European lineage." Ticks determined as R. turanicus s.l. from Cyprus clustered separately from the remaining clades of the R. sanguineus group, including R. turanicus s.s. The data show that R. sanguineus s.s. is present in the Canary Islands and Croatia, while R. sanguineus "southeastern lineage" is found in Cyprus.

A national survey of Ixodidae ticks on privately owned dogs in Italy

BackgroundThe geographical distribution of ticks on companion animals needs to be monitored to develop and plan effective control measures, as suggested by the European Scientific Counsel on Companion Animal Parasites. The aim of this study was to conduct the first Italian national survey of tick distribution on privately owned dogs.MethodsThe study was performed over 20 months (February 2016 - September 2017) and involved 153 veterinary practices in 64 different provinces covering 17/20 (85%) Italian regions. Participating practitioners were asked to examine five different dogs per month at random and complete a questionnaire for each dog. Differences in tick infestation associated with: sex, age and hair length (long and short); the dog’s habitat (indoor or outdoor/kennel); and the dog’s environment (urban or rural/sylvatic) were evaluated. The attachment site of ticks on the dog was also recorded. Acaricide efficacy was evaluated for the subset of dogs for which complete information on product used, date of sampling and date of last ectoparasiticide treatment was available.ResultsOf the 3026 dogs examined, 1383 (45.7%) were carrying at least one tick. Overall, 2439 tick samples were collected and a total of 14 tick species identified. Rhipicephalus sanguineus group were the most predominant ticks (63.6%), followed by Ixodes ricinus (30.6%) and I. hexagonus (5.6%). Twenty-four dogs had mixed tick infestations. Long-haired dogs had a higher tick infestation risk as did dogs with outdoor and rural/sylvatic lifestyles. Ticks were located on the head (37.4%), the neck (28.8%), the muzzle (15.5%) and the back (15.3%). A higher prevalence of Rhipicephalus was found in the interdigital spaces (10.8%) compared to Ixodes (0.2%). Finally, ectoparasiticide treatments were found significantly protective against tick infestation, especially orally administered formulations.ConclusionsPrivately owned dogs in Italy have a high prevalence (45.7%) of infestation with ixodid ticks and this risk varies by dog phenotype and lifestyle.

Tick (Acari: Ixodidae) infestations in cattle along Geba River basin in Guinea-Bissau

Tick infestations are a major problem for animal production in tropical areas where prevention and control remain deficient. The present study sought to assess the awareness of traditional cattle producers towards the importance of ticks and aimed at the identification of tick species infesting bovines within the Geba River basin, Guinea-Bissau. Interviews with producers revealed that the majority directly correlates the presence of ticks with the occurrence of diseases in cattle. However, insufficient or inadequate control approaches prevail. A total of 337 ticks were collected on bovines at 18 different villages (10 during dry season, and 8 during rainy season). The tick species collected during the dry season were Rhipicephalus (Boophilus) geigyi (56.5%), followed by Amblyomma variegatum (23.3%), Rhipicephalus (Boophilus) annulatus (17.6%) and Hyalomma truncatum (1%). In the rainy season A. variegatum was the most collected (88.9%), followed by R. (Boophilus) geigyi (4.2%), R. (Boophilus) annulatus (3.4%), Rhipicephalus sanguineus group (2.8%) and H. truncatum (0.7%). To support species identification, segments of both cytochrome c oxidase I (COI) and 12S ribosomal RNA (12S) genes were sequenced and the data gathered were analysed by maximum likelihood and parsimony. Morphological and genetic data of individual specimens gathered in this study provide relevant information for future studies on tick population dynamics in the region. In addition, it led to a deeper characterization of R. sulcatus and a R. sanguineus-like specimen, exploring their genetic relationship with other R. sanguineus, which supports their classification as distinct species within R. sanguineus group.

Anaplasma infection of Bactrian camels (Camelus bactrianus) and ticks in Xinjiang, China.

BackgroundTo date, anaplasmosis has been reported to be a subclinical disease in Indian and Arabian one-humped camels (Camelus dromedarius) and llamas (Lama glama). However, no information on Anaplasma infection in two-humped Bactrian camels (Camelus bactrianus) in China has been published to date. The aim of this study was to investigate the prevalence of Anaplasma spp. in domestic Bactrian camels and ticks in Xinjiang, China.FindingsA total of 382 ticks were collected from the Bactrian camels and from environmental sources. Of these, 84 were morphologically identified as belonging to the Rhipicephalus sanguineus group and genetically identified (12S rDNA, 16S rDNA and the cytochrome c oxidase 1 genes) as R. sanguineus group ticks (temporally designated as Rhipicephalus sp. Xinjiang). PCR testing showed that 7.2 % (20/279) of the camels harbored Anaplasma platys DNA. However, microscopic examination revealed no A. platys inclusions in blood smears from the camels. The PCR prevalence of A. platys DNA was 9.5 % (6/63) in Rhipicephalus sp. Xinjiang from the Bactrian camels and 14.3 % (3/21) in Rhipicephalus sp. Xinjiang from the vegetation. A. platys DNA was not detected by PCR in other tick species (Hyalomma asiaticum, Dermacentor niveus and Hyalomma dromedarii), and no other Anaplasma species were detected in these samples.ConclusionsThis is the first report of A. platys in Bactrian camels in Xinjiang, China. The moderate positivity observed indicates that these animals might be a natural host for this pathogen in China.

Distribution of hard tick species in Ankara, Turkey

A systematic study has been carried out on hard ticks from Ankara Province, Turkey. Between April 2010 and July 2012, 1800 tick specimens belonging to 9 species were identified at 31 locations in 9 districts. Tick species are listed as follows: Rhipicephalus sanguineus group (43.44%), Rhipicephalus bursa (36.67%), Hyalomma marginatum (8.83%), Haemaphysalis parva (6%), Hyalomma aegyptium (2.39%), Hyalomma excavatum (1.33%), Dermacentor marginatus (1.06%), Haemaphysalis punctata (0.22%), and Hyalomma detritum (0.06%). Ticks were collected from host animals and from vegetation via the flagging method. The species of the genus Rhipicephalus were present in most of the study areas, the most common being the Rhipicephalus sanguineus group (20/31). Hyalomma species were mostly collected from host animals, with Hyalomma marginatum being the most common species in this genus (8.83%). We also observed seasonal variations in abundance, with the highest number in May. The district with the most abundant ticks was determined to be Kizilcahamam, which had the highest tick abundance rate of 28.6%.

Further thoughts on the taxonomy and vector role of Rhipicephalus sanguineus group ticks

Rhipicephalus sanguineus is a tick species described in 1806 by Latreille, based on specimens probably collected in France. However, this is a taxon with uncertain morphological definition and recent studies have gathered irrefutable evidence supporting the existence of a cryptic species-complex under the name ‘R. sanguineus’, whose number of sibling species around the world has yet to be ascertained. This fact is of great medical and veterinary concern, also considering that ticks currently identified as ‘R. sanguineus’ have been regarded as proven or putative vectors of several pathogens infecting dogs and humans. Differences in the distribution and prevalence of some of these microorganisms (e.g., Ehrlichia canis and Hepatozoon canis) further support the existence of distinct species under the name ‘R. sanguineus’ and suggest that the vector competence of these tick species may vary. This article provides an account on the taxonomy and the vector role of ticks belonging to the R. sanguineus group in the light of recent research.

Molecular detection of tick-borne pathogens in Rhipicephalus sanguineus group ticks

The Rhipicephalus sanguineus group includes some of the most widespread dog ticks, whose identification currently represents a difficult task due to the morphological similarities of these ixodid species. Recently, following the morphological and molecular characterization of tick specimens collected from dogs in all continents, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus turanicus and three different operational taxonomic units (namely Rhipicephalus sp. I–III) have been identified. Therefore, a comprehensive molecular study has been herein carried out to detect selected canine vector-borne pathogens (i.e., Anaplasma platys, Cercopithifilaria spp., Ehrlichia canis and Hepatozoon canis) in ticks belonging to the R. sanguineus group. A total of 204 tick specimens from dogs were examined and identified as R. sanguineus s.l. (n=81), R. turanicus (n=17), Rhipicephalus sp. I (n=66), Rhipicephalus sp. II (n=37), and Rhipicephalus sp. III (n=3). PCR assays were performed to detect mitochondrial and ribosomal target genes of Cercopithifilaria spp., A. platys, E. canis and H. canis. Out of 204 specimens examined, 2.5%, 7.4% and 21.6% scored positive to A. platys, H. canis and Cercopithifilaria spp., respectively. In addition, co-infections with two pathogens (i.e., Cercopithifilaria bainae and A. platys or H. canis) were detected in four tick specimens. This study suggests a relationship between ticks belonging to the R. sanguineus group and the geographical distribution of A. platys, H. canis and Cercopithifilaria spp. However, the role of each representative tick species within the R. sanguineus group in the transmission of these canine pathogens needs to be further investigated.

Detection of Anaplasma platys in dogs and Rhipicephalus sanguineus group ticks by a quantitative real-time PCR

Anaplasma platys is an obligate intracellular, tick-borne pathogen of dogs, which causes canine infectious cyclic thrombocytopenia (CICT). The vector role of Rhipicephalus sanguineus group ticks has been only suggested, but definitive evidence is lacking. This study aimed to detect and quantify A. platys DNA in infected dogs and in their respective ticks through a quantitative real-time PCR assay. From March to May 2009, blood and tick samples from dogs residing in a CICT-endemic area were collected and molecularly analysed. Differences (p<0.05) were detected in the bacterial load between tick nymphs (3.5×10−2±2.5×10−2) and adults (female: 1.2×10−1±1.1×10−1; male: 9.3×10−2±1.2×10−2) and between unengorged (1.1×10−1±2.8×10−2) and partially or fully engorged ticks (1.9×10−1±2.7×10−2). No difference was found between ticks collected from positive (1.1×10−1±0.6×10−1) and negative (1.2×10−1±0.3×10−1) dogs (p>0.05). The mean bacterial load detected in positive dogs was lower than that in their respective ticks (p>0.05). This study provides circumstantial evidence of the putative role of Rhipicephalus sp. I as a vector of this pathogen.

Diversity of Cercopithifilaria species in dogs from Portugal

BackgroundFilarioids belonging to the genus Cercopithifilaria (Spirurida: Onchocercidae) have been described in dogs in association with Rhipicephalus sanguineus group ticks, which act as their biological vectors. This study represents the first investigation on Cercopithifilaria spp. in dogs from Portugal.FindingsDogs (n = 102) from the Algarve region (south of Portugal) were sampled by skin snip collection and tissues were left to soak overnight in saline solution. Sediments were observed under a light microscope and the detected microfilariae identified according to their morphology. Twenty-four dogs (23.5%) were found infected with at least one species of Cercopithifilaria, namely C. bainae (9.8%), C. grassii (3.9%) and Cercopithifilaria sp. II sensu Otranto et al., 2013 (13.7%). Results were confirmed by molecular amplification of partial cytochrome c oxidase subunit I and 12S rRNA genes and sequence analysis. Co-infections with more than one Cercopithifilaria species were detected in 3.9% of the animals.ConclusionsThis is the first report of Cercopithifilaria spp. in dogs from Portugal. The estimated level of infection with C. bainae, C. grassii and Cercopithifilaria sp. II suggests that these filarioids are prevalent in the canine population of southern Portugal.

Incidence of Cercopithifilaria bainae in Dogs and Probability of Co-Infection with Other Tick-Borne Pathogens

Background Cercopithifilaria bainae is a filarioid parasite that infects dogs, being transmitted by Rhipicephalus sanguineus group ticks in many countries of the Mediterranean basin. This study assessed the incidence density rate (IDR) of infection by C. bainae in dogs and the probability of co-infection with other tick-borne pathogens (i.e., Anaplasma platys, Babesia vogeli and Hepatozoon canis), in an area of high endemicity in southern Italy.Methodology/Principal FindingsFrom March 2011 to October 2012, a field study involving 58 young dogs naturally exposed to tick infestation was conducted. Skin and blood samples obtained from each dog six times during an 18-month period were tested for C. bainae by parasite detection within skin snip sediments, with subsequent confirmation through PCR and DNA sequencing. Dogs examined monthly for ticks and A. platys, B. vogeli and H. canis were microscopically and/or molecularly diagnosed and after the first and the second summer seasons, the IDR for positive animal-month at risk was 3.8% and 1.7% in November 2011 and October 2012, respectively. All 58 C. bainae-infected dogs were simultaneously infected with at least one other tick-borne pathogen. After the first summer season (assessment in November 2011), a C. bainae-infected dog had a 33% probability of being infected with H. canis or A. platys, whereas after the second tick season (assessment in October 2012) the probability of co-infection was 78%, 22% and 11% for H. canis, A. platys and B. vogeli, respectively.ConclusionsOur data indicate that tick-infested dogs are at risk of acquiring infection by C. bainae. In addition, the detection of C. bainae microfilariae indicates a prior tick exposure and, should stimulate testing for other tick-borne disease causing pathogens.

Ixodidae ticks in cattle and sheep in Sistan and Baluchestan Province (Iran).

This survey was conducted to investigate the presence and abundance of hard tick species (Acari: Ixodidae) on cattle and sheep in Sistan and Baluchestan Province (Iran). Between 2010 and 2011, a total of 1,403 ticks was collected from 332 infested cattle and 1,480 ticks were collected from 602 infested sheep during the seasons of tick activity. The species collected from cattle were Hyalomma marginatum (46.04%), Hyalomma excavatum (25.51%), Hyalomma anatolicum (10.33%), Hyalomma asiaticum (6.34%), and ticks of the Rhipicephalus sanguineus group (11.76%); while the species collected from sheep were of the Rhipicephalus sanguineus group (34.66%), H. marginatum (25.60%), H. excavatum (27.97%), H. asiaticum (9.45%) and Hyalomma scupense (2.29%). The results show that H. marginatum, H. excavatum, as well as ticks of the R. sanguineus group are dominant in the surveyed area.

Abstracts of the 1st Conference on Neglected Vectors and Vector-Borne Diseases (EurNegVec): with Management Committee and Working Group Meetings of the COST Action TD1303, April 8-11, 2014, Cluj-Napoca, Romania.

Ticks are important vectors of disease and transmit an extensive range of viral, bacterial and protozoan pathogens to livestock in a wide variety of habitats. In recent years, diseases such as babesiosis, ehrlichiosis and anaplasmosis have all shown evidence of increased prevalence and distribution in various parts of Europe. However data concerning the prevalence of ticks and tick borne diseases present in livestock and humans in Greece are limited. In order to fill this gap we performed the current study to define the existence and prevalence of different tick species found in farm animals and humans. As regards livestock, we focused on ruminants (mainly sheep and goats and, in a lesser extent, cattle) since they are the only ones spend time on pastures. A sufficient number of farms all over the country were visited during 2 tick seasons (from March to October), taking different habitats and animal density around Greece into account. Ticks collected from humans originated from infected individuals who visited hospitals. In total, 2676 ticks were collected from 26 different prefectures (mainland and islands) all over Greece. From those, 1,883 were coming from sheep (1201) and goats (681) and identified as: Rhipicephalus sanguineus 1,216 (64.65%); R. bursa 495 (26.3%); R. camicasi 12 (0.6%); R. turanicus 70 (3.7%); Ixodes ricinus 1 (0.05%); Dermacentor marginatus 47 (2.5%); Hyalomma marginatum 5 (0.3%); H. excavatum 2 (0.1%), H. dromedarii 31 (1.6%) H. rufipes 2 (0.1%); H. impeltatum 1 (0.05%); and Rhipicephalus nymph 1 (0.05%). More than half (54.3%) of the above were found in an altitude of 0-300 meters, 37.1% in an altitude of 301-800m and 3.2% in an altitude of >800m. 142 ticks originated from cattle and were identified as: R. sanguineus 15 (10.5%); R. bursa 6 (4.2%); R. camicasi 5 (3.5%); R. turanicus 6 (4.2%); H. marginatum 24 17%); H. excavatum 8 (5.6%); H. dromedarii 67 (47.2%); H. rufipes 4 (2.8%); H. impeltatum 1 (0.7%); H. anatolicum 3 (2.1%) and H. turanicum 3 (2.1%). Finally, 701 ticks were coming from humans and identified as: R. sanguineus 562 (80.17%); R. bursa 23 (3.28%); R. turanicus 34 (4.85%); R. annulatus 5 (0.71%); H. marginatum 30 (4.28%); H. excavatum 2 (0.28%); H. rufipes 11 (1.57%); Dermacentor marginatus 2 (0.28%); Ixodes ricinus 6 (0.85%); I. gibosus 6 (0.85%) and Rhipicephalus nymphs 20 (2.85%). In conclusion, the majority of ticks found in both animal species and humans examined belonged in the Rhipicephalus sanguineus group which is the main vector of Rickettsia conorii, while Hyalomma marginatum, the vectors of CCHF virus, were also present. The above results were more or less anticipated given the climatic conditions of the area, fact that also explains the low prevalence of Ixodes spp.

The enigma of the dog mummy from Ancient Egypt and the origin of ‘Rhipicephalus sanguineus’

BackgroundTicks belonging to the Rhipicephalus sanguineus group are amongst the most important vectors of pathogenic microorganisms to dogs and humans. However, the taxonomy of this species group is still the subject of debate, especially because there is no type specimen or reliable morphological description for Rhipicephalus sanguineus sensu stricto. Recently, a comprehensive morphological and genetic study on representative tick specimens from Europe, Africa, Americas, and Oceania, revealed the existence of at least four morphologically and genetically distinct species under the name ‘R. sanguineus’ infesting dogs from different countries.MethodsHerein, we examined morphologically tick specimens retrieved on a dog mummy from Ancient Egypt (ca. 1st century – 4th century A.D.). The dog mummy and associated ticks were found during an archaeological expedition conducted in El Deir.ResultsScanning electron micrographs allowed us to assess their identity as belonging to the R. sanguineus group. In addition on the basis of the scutal punctation pattern, spiracular plates, width of dorsal tail of spiracular plates relative to the adjacent festoon, female genital aperture, male adanal plates and accessory shields, these ticks were tentatively identified as Rhipicephalus sp. II (=temperate species).ConclusionsIt can be concluded that R. sanguineus group ticks have infested dogs living in the Mediterranean region since ancient times. This finding represents the oldest record of ticks on any animal species and adds a new piece in the complex puzzle regarding tick parasitism on dogs and humans and their role as vectors of pathogens.

Crimean-Congo Hemorrhagic Fever in European Part of Turkey: Genetic Analysis of the Virus Strains from Ticks and a Seroepidemiological Study in Humans

A survey of ticks from domestic ruminants, together with a serosurvey in humans was conducted in Thrace (northwestern Turkey) to evaluate the prevalence of Crimean-Congo hemorrhagic fever virus (CCHFV) in ticks and humans. More prevalent ticks were Hyalomma marginatum, Hyalomma aegyptium, Rhipicephalus bursa, and Rhipicephalus (Boophilus) annulatus, with low numbers of Dermacentor marginatus, Rhipicephalus sanguineus group, and Ixodes ricinus. No differences in the tick faunal composition were found among surveyed provinces. CCHFV was detected using specific primers for strains belonging to both Europe 1 and Europe 2 clades in a total of 15 pools of ticks collected in nine localities. The maximum likelihood estimate of infection rate was calculated as 0.72/100 ticks (95% CI = 0.42-1.16). Viral RNA was observed only in H. marginatum, R.(B.) annulatus, and R. bursa with overall maximum likelihood estimate infection rates being 0.93 (95% CI = 0.35-2.05), 0.74 (95% CI = 0.24-1.78), and 1.67 (95% CI = 0.69-3.46), respectively. The surveyed region is the only place where both viral strains are circulating together in nature in Turkey. Results from serosurvey on 193 samples from three localities in the region showed that immunoglobulin M and immunoglobulin G rates are compatible with an epidemiological situation in which the virus has been present for a long time and is not the result of a recent invasive event from the main epidemic center in Anatolia (north-central Turkey). Seropositivity rates cannot be compared against the tick faunal composition, because of the homogeneity in the results about tick surveys. The high rate of seropositivity, and the prevalence of CCHFV in both Europe 1 and 2 clades among the ticks, but few clinical cases suggest that the circulation of both viral strains may confer protection against the CCHFV infection.

Genetic analysis of ticks belonging to the Rhipicephalus sanguineus group in Latin America

Phylogenetic analyses based on mitochondrial 16S rDNA sequences were generated from Rhipicephalus sanguineus group specimens collected in 29 localities among 9 Latin-American countries, plus ticks collected in South Africa, Spain, and Italy. Sequences from Latin America generated six different haplotypes (A, B, C, D, E, and F). Phylogenetic analyses generated trees that segregated our tick sequences into two distinct clades: one is represented by haplotypes A–C, and South African R. sanguineus and Rhipicephalus turanicus ticks; the second clade is represented by haplotypes D–F, and European R. sanguineus and R. turanicus ticks. When haplotypes A–F are plotted in the Latin America map according to their geographical coordinates, it is clearly seen that haplotypes D–F are restricted to the southern portion of this continent, whereas haplotypes A–C are distributed in areas between northern Mexico and Brazil (except for the extreme south of this last country, where haplotype E was present). Hence, our phylogenetic analyses separated New World specimens of R. sanguineus into two distinct clades, one represented by tropical and subtropical populations (haplotypes A–C), here designated as the ‘tropical’ species. On the other hand, haplotypes D–F are here designated as the ‘temperate’ species because of their distribution in the southern portion of South America. Until recently, it was assumed that the R. sanguineus group was represented by a single species in the New World, namely R. sanguineus. While the present results coupled with recent studies support the presence of at least two species under the taxon R. sanguineus in the New World, they also show that even in the Old World, the taxon R. sanguineus might be represented by more than one species, since our phylogenetic analysis segregated European and South African R. sanguineus ticks into two distinct clades. The same can be applied for Spanish and South African R. turanicus.

Ticks (Acari: Ixodidae) infesting camels (&lt;i&gt;Camelus dromedarius&lt;/i&gt;) in Northern Sudan

Monthly total body tick collections from 13-20 camels were conducted for 2 consecutive years (2000-2001) in Northern Sudan. Tick populations were correlated with locality, season, predeliction site, sex and coat colour. Hyalomma dromedarii was found to be the predominant (89%) tick species infesting the camels. Other tick species found in very low numbers were Hyalomma impeltatum (7.7%), Hyalomma anatolicum anatolicum (3.3%), Hyalomma truncatum (0.29%), Hyalomma marginatum rufipes (0.25%), Rhipicephalus praetextatus (0.30%) and Rhipicephalus sanguineus group (0.09%). Nymphs of the genus Hyalomma were collected in significant numbers. Adult ticks significantly preferred to attach to the lower parts of the camel's body for feeding while the nymphs preferred the back of the animal. Female camels harboured more ticks than males while higher infestations were recorded on camels with a grey coat colour compared to those with a brown coat colour. Ticks were found on camels throughout the year and increased in numbers during March to October with a peak in September.