Comments on article ”First report of Ixodes frontalis (Acari: Ixodidae) in Finland, an example of foreign tick species transported by a migratory bird” (Memoranda Soc. Fauna Flora Fennica 85:16–19. 2009)

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Differential diagnosis of three common Ixodes spp. ticks infesting songbirds of western Europe : Ixodes arboricola, I. frontalis and I. ricinus

The three most common Ixodes spp. ticks found on songbirds in Western Europe are Ixodes frontalis, I. arboricola and I. ricinus. As the latter species is a generalist, it shares several avian hosts with the two strictly ornithophilic species. Infestations of the three species can overlap in time and space, implying that tick-borne pathogens maintained by the ornithophilic ticks and their hosts could be bridged by I. ricinus to non-avian hosts. Whereas the endophilic Ixodes arboricola only occurs in cavities, I. frontalis has been collected frequently by flagging methods from understory vegetation, which is also the habitat of the fielddwelling I. ricinus. As the latter two species have rather similar morphological characteristics, they can easily be confused with each other. In this study, we present scanning electron photomicrographs of all developmental stages of I. arboricola and I. frontalis, and provide a differential diagnosis key to distinguish the ornithophilic ticks from I. ricinus. In addition, we interpreted their phylogenetic associations based on mitochondrial 16S rDNA with other Ixodes spp. ticks (I. lividus, I. turdus, I. brunneus, I. vespertilionis, I. trianguliceps, I. hexagonus, I. scapularis).Fund for Scientific Research –Flanders (FWO)http://www.elsevier.com/locate/ttbdishb201

New foci of Rhipicephalus microplus in West Africa

The invasive character of Rhipicephalus microplus was observed in Benin, the second West-African country from which this ticks species has been collected after the initial confirmed record in Ivory Coast in 2007. A cross-sectional study was carried out in the Department of Mono to examine the presence of the tick R. microplus. The survey covered 9 herds (villages) in an agro-ecological zone inhabited by agro-pastoralists, including the State Farm of Kpinnou that imported Girolando cattle from Brazil. Almost 800 ticks were sampled from 36 cattle, on average four cattle per village. The morphological identification revealed ticks of two different genera: Rhipicephalus and Amblyomma. Rhipicephalus microplus was the only representative of the species previously known as Boophilus or blue ticks. Its taxonomic identity was confirmed molecularly by PCR–RFLP. A comparison was made with the situation of R. microplus in Brazil.The Belgian Development Cooperation (BDC) for the financial support of this research project as part of a Masters programme offered by the Institute of Tropical Medicine in Antwerp, Belgium.http://www.springerlink.com/content/100158/ab201

Association of environmental traits with the geographic ranges of ticks (Acari: Ixodidae) of medical and veterinary importance in the western Palearctic. A digital data set

We compiled information on the distribution of ticks in the western Palearctic (11oW, 45oE; 29oN, 71oN), published during 1970–2010. The literature search was filtered by the tick’s species name and an unambiguous reference to the point of capture. Records from some curated collections were included. We focused on tick species of importance to human and animal health, in particular: Ixodes ricinus, Dermacentor marginatus, D. reticulatus, Haemaphysalis punctata, H. sulcata, Hyalomma marginatum, Hy. lusitanicum, Rhipicephalus annulatus, R. bursa, and the R. sanguineus group. A few records of other species (I. canisuga, I. hexagonus, Hy. impeltatum, Hy. anatolicum, Hy. excavatum, Hy. scupense) were also included. A total of 10,280 records was included in the data set. Almost 42 % of published references are not adequately referenced (and not included in the data set), host is reported for only 61 % of records and a reference to time of collection is missed for 84 % of published records. Ixodes ricinus accounted for 44.3 % of total records, with H. marginatum and D. marginatus accounting for 7.1 and 8.1 % of records, respectively. The lack of homogeneity of the references and potential pitfalls in the compilation were addressed to create a digital data set of the records of the ticks. We attached to every record a coherent set of quantitative descriptors for the site of reporting, namely gridded interpolated monthly climate and remotely sensed data on vegetation (NDVI). We also attached categorical descriptors of the habitat: a standard classification of land biomes and an ad hoc classification of the target territory from remotely sensed temperature and NDVI data. A descriptive analysis of the data revealed that a principal components reduction of the environmental (temperature and NDVI) variables described the distribution of the species in the target territory. However, categorical descriptors of the habitat were less effective. We stressed the importance of building reliable collections of ticks with specific references as to collection point, host and date of capture. The data set is freely downloadable

Morphological identification of ticks (Acari: Ixodidae) infesting donkeys (Equus asinus) in Maputo Province, Mozambique

Donkeys (Equus asinus) are rustic animals, but in Africa’s poorest regions, they can present multiple health problems, including tick infestation. The study’s objective was to determine the species composition of ticks that infest donkeys in Maputo Province (Mozambique). Ticks were collected in five conveniently selected southern districts of Maputo Province (Moamba, Matutuíne, Marracuene, Boane, and Matola) and were identified to species level using a stereoscopic microscope with the aid of dichotomous identification keys. In total, 500 ticks were collected from all 88 selected donkeys. Three genera of ticks were identified, namely Rhipicephalus (97.2%; 486/500), Amblyomma (2.2%; 11/500), and Hyalomma (0.6%; 3/500). Seven species were identified, of which Rhipicephalus evertsi evertsi with 50.4% (252/500) was the most prevalent, followed by Rhipicephalus appendiculatus (27.4%; 137/500), Rhipicephalus turanicus (11.6; 10/500), Rhipicephalus (boophilus) microplus (6.8; 20/500), Amblyomma hebraeum (2.2%; 11/500), Rhipicephalus sanguineus (1%; 5/500) and Hyalomma truncatum (0.6%; 3/500). Rhipicephalus evertsi evertsi occurred in all locations, whereas Hyalomma truncatum occurred only in the Boane district. Males were the most prevalent (67.2%; 336/500). The study revealed that donkeys in Maputo Province were infested with seven tick species of which R. evertsi evertsi was the main species.https://link.springer.com/journal/10493hj2023Veterinary Tropical Disease

Mitochondrial phylogeography and population structure of the cattle tick Rhipicephalus appendiculatus in the African Great Lakes region

Abstract Background The ixodid tick Rhipicephalus appendiculatus is the main vector of Theileria parva, wich causes the highly fatal cattle disease East Coast fever (ECF) in sub-Saharan Africa. Rhipicephalus appendiculatus populations differ in their ecology, diapause behaviour and vector competence. Thus, their expansion in new areas may change the genetic structure and consequently affect the vector-pathogen system and disease outcomes. In this study we investigated the genetic distribution of R. appendiculatus across agro-ecological zones (AEZs) in the African Great Lakes region to better understand the epidemiology of ECF and elucidate R. appendiculatus evolutionary history and biogeographical colonization in Africa. Methods Sequencing was performed on two mitochondrial genes (cox1 and 12S rRNA) of 218 ticks collected from cattle across six AEZs along an altitudinal gradient in the Democratic Republic of Congo, Rwanda, Burundi and Tanzania. Phylogenetic relationships between tick populations were determined and evolutionary population dynamics models were assessed by mismach distribution. Results Population genetic analysis yielded 22 cox1 and 9 12S haplotypes in a total of 209 and 126 nucleotide sequences, respectively. Phylogenetic algorithms grouped these haplotypes for both genes into two major clades (lineages A and B). We observed significant genetic variation segregating the two lineages and low structure among populations with high degree of migration. The observed high gene flow indicates population admixture between AEZs. However, reduced number of migrants was observed between lowlands and highlands. Mismatch analysis detected a signature of rapid demographic and range expansion of lineage A. The star-like pattern of isolated and published haplotypes indicates that the two lineages evolve independently and have been subjected to expansion across Africa. Conclusions Two sympatric R. appendiculatus lineages occur in the Great Lakes region. Lineage A, the most diverse and ubiquitous, has experienced rapid population growth and range expansion in all AEZs probably through cattle movement, whereas lineage B, the less abundant, has probably established a founder population from recent colonization events and its occurrence decreases with altitude. These two lineages are sympatric in central and eastern Africa and allopatric in southern Africa. The observed colonization pattern may strongly affect the transmission system and may explain ECF endemic instability in the tick distribution fringes

SNP analysis infers that recombination is involved in the evolution of Amitraz resistance in Rhipicephalus microplus

Rhipicephalus microplus, better known as the Asiatic cattle tick, is a largely invasive ectoparasite of great economic importance due to the negative effect it has on agricultural livestock on a global scale, particularly cattle. Tick-borne diseases (babesiosis and anaplasmosis) transmitted by R. microplus are alarming as they decrease the quality of livestock health and production. In sub-Saharan Africa, cattle represent a major source of meat and milk, but this region of the world is severely affected by the Rhipicephalus microplus tick. The principal method for tick control is the use of chemical acaricides, notably amitraz, which was implemented in the 1990’s after resistance to other acaricides surfaced. However, the efficiency of chemical control is hindered by an increase in the frequency of mutant resistance alleles to amitraz in tick populations. Presently, the only way to assess amitraz resistance is by means of larval packet tests, but this technique is time-consuming and not particularly cost effective. The main aims of this study were three-fold. First, we attempted to correlate two known SNPs in the octopamine/tyramine (OCT/Tyr) receptor with amitraz resistance in South African field samples of R. microplus. Second, we calculated gametic disequilibrium for these SNPs to determine whether they are randomly associated. Lastly, we conducted a study to assess the evolutionary effects of recombination within the OCT/ Tyr receptor. Our results confirmed that the two SNPs are associated with amitraz resistance in the South African tick strain, and that they are in gametic disequilibrium. Additionally, recombination was detected in the OCT/Tyr receptor generating two recombinant haplotypes. These results are of concern to farmers in sub-Saharan Africa, and the emergence of amitraz resistance should be closely monitored in future. Therefore, we present a quick and affordable RFLP based diagnostic technique to assess amitraz resistance in field samples of R. microplus.S1 Fig. Subpopulation structure of ticks across South Africa. Ticks from each farm were placed into subpopulations (1–15) depending on the region from which they were collected. Grid blocks were constructed 300 x 300 km over the country for accurate overall segregation of populations. The farms from which tick samples were analyzed are indicated in the table, along with their grid block number and province. Farm numbers correspond with sample number, e.g. sample 44.1MF is sample 1 of female R. microplus from farm 44.S1 Table. GenBank accession numbers for all R. microplus OCT/Tyr receptor sequences.S2 Table. Genotypes of field samples of R. microplus ticks at the two published SNP positions.S3 Table. Rhipicephalus microplus larval packet test results.Funding was provided by (a) Gauteng Department of Agriculture and Rural Development, C Maritz-Olivier. (b) Zoetis South Africa (Pty) Ltd., C Maritz-Olivier (c) National Research Foundation, THRIP grant nr: 83890.http://www.plosone.orgam201

First interception of Aedes (Stegomyia) albopictus in Lucky bamboo shipments in Belgium

Six gel-and five water-transported Dracaena braunii shipments originating from the South coast of China were screened for exotic mosquito species during a surveillance project on exotic vectors in Belgium. In November 2013, a live Aedes (Stegomyia) albopictus larva was detected in a gel substrate. This is the first direct evidence of the importation of Ae. albopictus on gel-transported Lucky bamboo. It also confirms that the importation risk of Ae. albopictus by transport of ornamental bamboo plants remains. In addition to the registration of appropriate biocides, a structured and permanent surveillance programme is needed in Belgium to allow for the early detection of invasive mosquito species and the timely implementation of control measures. JournalThe Federal Agency for the Safety of the Food Chain (FASFC)http://e-m-b.orgam201