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Hyalomma ticks are important vectors of pathogens affecting human and animal health. This study aimed to assess the outputs of three molecular markers (16S, 12S rRNA, and COI) for accurate tick species molecular identification, genetic diversity assessment, and phylogenetic positioning of Hyalomma tick specimens from Tunisia. A total of 20 tickspecimens were collected from different hosts including cattle, camels, and turtles in nine Tunisian governorates. Morphological diagnosis confirmed five Hyalomma species: H. scupense, H. marginatum, H. excavatum, H. aegyptium, and H. dromedarii. Molecular analysis confirmed species’ identification and revealed varying levels of genetic diversity within each species. Within the H. scupense and H. aegyptium species, low genetic diversity was observed, with no variable sites detected in the 16 S and 12 S rRNA markers, except for a single site in H. aegyptium’s COI marker. H. marginatum isolates showed moderate diversity, with no variable sites in the 16S and 12S rRNA markers, and four variable sites in the COI marker. In contrast, H. excavatum and H. dromedarii isolates exhibited higher diversity, with variable sites identified in all three markers (16S, 12S rRNA, and COI). Phylogenetic analysis revealed that, with the exception of H. scupense, the COI marker exhibited superior discriminatory power compared to the 16 S and 12 S rRNA markers. This enabled the discernment of distinct genetic clusters within each species. These findings underscore the importance of utilizing multiple molecular markers for confirming morphological diagnosis and specifically highlight the significance of the COI marker in assessing the genetic diversity and phylogenetic relationships of Hyalomma ticks. By employing these markers, particularly COI, valuable insights into the evolutionary dynamics and epidemiological significance of Hyalomma ticks can be gained, facilitating targeted control measures against tick-borne diseases. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis (B. thuringiensis) is considered one of the most important entomopathogenic microorganisms. It produces potent toxins against insects. Therefore, the present study investigates the bioacaricidal properties of B. thuringiensis on the Hyalomma tick species. Firstly, we identify Hyalomma ticks based on morphological screening and molecular characterization. The cytochrome C oxidase subunit I (COX1) gene was selected for the polymerase chain reaction (PCR) analysis, which resulted in the amplification of 656 bp. The amplified products were sequenced, and the isolated (COX1) gene of ticks was submitted to the gene bank of NCBI (Accession No. OR077934.1). The nucleotide sequences were retrieved from the NCBI data bank by BLASTn analysis, which confirmed that all obtained sequences belong to genus Hyalomma, and multiple alignments confirmed that the sequence of Hyalomma anatolicum Tandojam‐isolate (HA‐TJ) 100% aligned with Hyalomma analoticum KP792577.1, Hyalomma detritum KP792595.1, Hyalomma excavatum KX911989.1, and H. excavatum OQ449693.1. The generated phylogenetic tree confirmed that sequences of HA‐TJ COX1 clustered with a single clad of H. analoticum, H. excavatum, and H. detritum. The acaricidal effect of B. thuringiensis toxins B. thuringiensis spore crystal mix (BtSCM) and B. thuringiensis crystal proteins (Btcps) was evaluated against larvae and adult life stages of Hyalomma ticks in vitro. We applied Btcps and BtSCM separately with different concentrations and calculated the mortality percentage. Adult mortality was estimated at the 8th, 10th, 12th, and 15th days posttreatment and larval mortality after 24 h. During treatment of the adult life stage, at first, ticks were immersed in different concentrations of Btcps and BtSCM for 5 min after the treatments, and the samples were transferred to sterile containers and placed in an incubator with 80% humidity at 23°C. Furthermore, Btcps produced the highest mortality on Day 15, 89 ± 1.00% at a concentration of 3000 μg/mL, followed by the 12th, 10th, and 8th days produced 83 ± 1.91%, 70 ± 1.15%, and 61 ± 1.00%, respectively. BtSCM produced mortality of 69 ± 1.91% on Day 15 at a concentration of 3000 μg/mL, followed by the 12th, 10th, and 8th days at 57 ± 2.51%, 37 ± 1.91%, and 34 ± 2.00%. The present study revealed that B. thuringiensis toxins produced a significant (p < 0.05) increase in mortality rate in adults of Hyalomma ticks. Additionally, Btcps and BtSCM were used to treat the larval stage. The treatments were applied to calculate the mortality percentage via the Laravel packet test. At a 1500 μg/mL concentration, Btcps resulted in the highest mortality of 98 ± 1.15%; this was followed by 1250 μg/mL, 1000 μg/mL, and 750 μg/mL, which produced mortalities of 76 ± 1.63%, 60 ± 1.63%, and 56 ± 1.63%, respectively. In addition, BtSCM produced a mortality rate of 79 ± 2.51% at a concentration of 1500 μg/mL. Furthermore, 75 ± 2.51%, 65 ± 1.91%, and 58 ± 1.15% mortality were observed at concentrations of 1250 μg/mL, 1000 μg/mL, and 750 μg/mL, respectively. The results showed a significant (p < 0.05) increase in larval mortality compared to the control group. We conclude that B. thuringiensis toxins are applicable as a bioacaricide. [ABSTRACT FROM AUTHOR]

Serosurvey results for Crimean-Congo hemorrhagic fever virus antibodies in dromedary camels in Algeria indicate that the pathogen is circulating endemically in desertic areas, despite the hostile environment. Thus, dromedaries are suitable sentinels for detecting human risk for Crimean-Congo hemorrhagic fever in desertic areas.

We conducted a retrospective serosurvey for antibodies against Crimean-Congo hemorrhagic fever virus in wild ungulates along the eastern Mediterranean Coast of Spain. The virus has been endemic in this region since 2010 but is mainly restricted to geographic clusters with extremely high seropositivity associated with high density of bovids. [ABSTRACT FROM AUTHOR]

Crimean-Congo hemorrhagic fever (CCHF) is one of the utmost broadly distributed tick-borne viruses, with an infection resulting in a fatality rate of up to 30%. During this study period, 25,000 hard adult ticks of Hyalomma species were collected from freshly slaughtered imported camels to determine the presence of Crimean-Congo hemorrhagic fever virus (CCHFV) and genetic lineage of the virus. Ticks were pooled and analyzed for the existence of CCHFV using nested RT- PCR and real-time reverse transcription PCR; the genome was detected in 18 (1.44%) tick pools. Partial genome sequences reveal an adjacent relationship with strains from South Africa to Namibia, Nigeria, Sudan, Senegal, and Mauritania, corresponding to the Africa I and III genotypes. This study indicates the presence of CCHFV in Egypt and illustrates the potential for tick-borne dissemination of the virus. Further studies focused on not only tick samples, but also human samples are epidemiologically valuable to obtain exact data in the region. [ABSTRACT FROM AUTHOR]

We conducted a cross-sectional survey of Crimean-Congo hemorrhagic fever virus (CCHFV) in dromedary camels and attached ticks at 3 locations in the United Arab Emirates. Results revealed a high prevalence of CCHFV-reactive antibodies in camels and viral RNA in ticks and camel serum, suggesting the virus is endemic in this country.

We conducted a cross-sectional survey of Crimean-Congo hemorrhagic fever virus (CCHFV) in dromedary camels and attached ticks at 3 locations in the United Arab Emirates. Results revealed a high prevalence of CCHFV-reactive antibodies in camels and viral RNA in ticks and camel serum, suggesting the virus is endemic in this country. [ABSTRACT FROM AUTHOR]

• First detection of CCHF virus in ticks collected from animals in the Sudan. • Detection of a new genetic lineage of the CCHF virus in the Sudan. • Hyalomma impeltatum as a vector of CCHF virus in the Sudan. An evidence for Crimean-Congo hemorrhagic fever virus (CCHFV) was found in Hyalomma impeltatum ticks collected from sheep in North Kordofan in the Sudan. Based on sequencing of the partial segment S, the detected virus belongs to lineage I with closest similarity to CCHFV strains from Senegal. So far, this lineage is unknown in the Sudan. [ABSTRACT FROM AUTHOR]

Several species of the spotted fever group rickettsiae have been identified as emerging pathogens throughout the world, including in Africa. In this study, 197 Hyalomma ticks ( Ixodida: Ixodidae) collected from 51 camels ( Camelus dromedarius) in Kano, northern Nigeria, were screened by amplification and sequencing of the citrate synthase ( gltA), outer membrane protein A ( ompA) and 17-kDa antigen gene fragments. Rickettsia sp. gltA fragments were detected in 43.3% (42/97) of the tick pools tested. Rickettsial ompA gene fragments (189 bp and 630 bp) were detected in 64.3% ( n = 27) and 23.8% ( n = 10) of the gltA-positive tick pools by real-time and conventional polymerase chain reaction ( PCR), respectively. The amplicons were 99-100% identical to Rickettsia aeschlimannii TR/ Orkun- H and R. aeschlimannii strain EgyRickHimp-El-Arish in GenBank. Furthermore, 17-kDa antigen gene fragments of 214 bp and 265 bp were detected in 59.5% ( n = 25) and 38.1% ( n = 16), respectively, of tick pools, and sequences were identical to one another and 99-100% identical to those of the R. aeschlimannii strain Ibadan A1 in GenBank. None of the Hyalomma impressum ticks collected were positive for Rickettsia sp. DNA. Rickettsia sp. gltA fragments (133 bp) were detected in 18.8% of camel blood samples, but all samples were negative for the other genes targeted. This is the first report to describe the molecular detection of R. aeschlimannii in Hyalomma spp. ticks from camels in Nigeria. [ABSTRACT FROM AUTHOR]

Tick-borne pathogens can spread easily through the movements of infested birds. An important example is viruses that pose a threat to humans and that are carried in Hyalomma ticks that move from Africa into south-western Europe. This study evaluates the probability of arrival of migrating birds from Africa into Spain and the environmental suitability of different regions of Spain for the survival of tick stages introduced by these birds. This evaluation produced a spatial risk index measuring the probability that foreign tick populations will survive in the target area. Periods of highest risk were observed for large areas of Spain, from the second fortnight of April to the second fortnight of May. Although birds may arrive as early as January and massive migrations may take place in March, the environmental suitability for Hyalomma marginatum ticks is low in these periods and high mortality of the spread stages (nymphs) is expected. This study introduces new methods of objective analysis based on spatial and process-driven models for both ticks and hosts and critically evaluates the usefulness of spatial spreading methods for assessing the risk of tick-borne pathogens. [ABSTRACT FROM AUTHOR]