Prevalence, Distribution, and Molecular Record of Four Hard Ticks from Livestock in the United Arab Emirates

Prevalence and associated risk factors of ixodid tick species infesting cattle and sheep in Balochistan, Pakistan

Tick infestation poses a serious threat to animal health, leading to significant losses in terms of vector-borne disease transmission, reduced live weight, lower quality hides, decreased milk production, and impaired reproduction in tropical and subtropical regions worldwide. This study aimed to determine the prevalence, seasonal variation, distribution pattern, and associated risk factors of Ixodid family tick species in the cattle and sheep population of three different districts in Balochistan, Pakistan. This study employed a convenient sampling method, collecting 4080 adult ticks from 816 cattle and sheep of various breeds, ages, and sexes. Specific morphological keys were used to identify the ticks up to the genus and species level. Among cattle, the highest prevalence was recorded for R. (B) annulatus (27.01%), followed by R. (B) microplus (24.02%), and H. anatolicum (20.54%). H. dromedarii (5.29%) was the least prevalent species observed in cattle. In the sheep population, H. anatolicum (30.34%) showed the highest prevalence, followed by H. marginatium (22.99%), and R. (B) annulatus (20.88%). H. dromedarii (6.96%) was the least prevalent species observed in sheep. The prevalence of R. (B) decoloratus, H. anatolicum and H. dromedarii was found to be significantly associated (P < 0.05) with the breed, age, and sex of both cattle and sheep. However, the presence of R. (B) annulatus, R. (B) microplus and H. marginatium tick species showed no significant association (P > 0.05) with these factors. In addition, the prevalence of ticks was higher in younger, female, and crossbred Friesian cattle compared to adults, males, and other breeds. Conversely, the prevalence of ticks was higher in adult, female and Hernai breed of sheep in the studied area. In conclusion, R. (B) annulatus and H. anatolicum are the dominant tick species infesting the cattle and sheep population in Balochistan. Consequently, this study provides valuable insights for developing practical and effective control measures against ticks and tick-borne diseases in the sheep and cattle population of Balochistan, Pakistan.

The first record of ostrich feather louse (Struthiolipeurus struthionis) collected from farmed ostriches (Struthio camelus) in the United Arab Emirates

Background and Aim

Ostrich (Struthio camelus) farming in the United Arab Emirates (UAE) is a relatively new field of farming. Farmed ostriches are susceptible to ectoparasite infestation, which affects their production. This study was conducted to estimate the prevalence of ectoparasites on ostriches raised on a farm in Abu Dhabi Emirate.

Materials and Methods

The feathers of 42 ostriches (26 females and 16 males) were collected and morphologically examined for ectoparasites. In total, 283 lice (89 males and 194 females) were collected from birds. However, there were no ticks or other ectoparasites. Lice were preserved in 1.5 mL tubes containing 70% ethanol and were later identified using taxonomic keys. The prevalence, mean intensity of infection, and mean abundance were estimated.

Results

One louse species, Struthiolipeurus struthionis was identified. To the best of our knowledge, this is the first report of S. struthionis in ostriches raised in the UAE with an overall prevalence of 88%. The prevalence of lice was significantly higher in July (100%) than that in May (66.7%). Likewise, the mean intensity and abundance of lice were significantly higher in June (10.6 and 9.94, respectively) than in May (3.25 and 2.2, respectively).

Conclusion

The high prevalence of lice poses a serious risk to ostrich farming by negatively affecting the health and productivity of ostriches.

Molecular screening of Amblyomma species (Acari: Ixodidae) imported from African countries to Egypt, with the first report of Amblyomma latum from the ball python, Python regius (Squamata: Pythonidae)

Amblyomma species are non-endemic ticks in Egypt, which have been recorded from imported animals. This study was carried out in 2022 to monitor Amblyomma spp. from dromedary camels, cattle, and snakes in Egypt. During this study, 400 camels, 200 cattle, and two snakes (Pythonidae) were inspected for tick infestation. Collected specimens were identified based on morphological characters and confirmed by phylogenetic analysis of the 12S rRNA gene. Camels were infested by adult specimens of Amblyomma variegatum and Amblyomma lepidum, but no Amblyomma spp. were collected from cattle. Amblyomma variegatum showed high genetic similarity to other A. variegatum from Guinea-Bissau and São Tomé (> 99.99%), and A. lepidum showed high genetic similarity to other A. lepidum from Israel and Sudan (99.99%). Amblyomma latum is recorded in Egypt from the ball python snake for the first time and showed high genetic similarity with South African A. latum (99.87%).

Virome diversity of Hyalomma dromedarii ticks collected from camels in the United Arab Emirates

Background and Aim: Viruses are important components of the microbiome of ticks. Ticks are capable of transmitting several serious viral diseases to humans and animals. Hitherto, the composition of viral communities in Hyalomma dromedarii ticks associated with camels in the United Arab Emirates (UAE) remains unexplored. This study aimed to characterize the RNA virome diversity in male and female H. dromedarii ticks collected from camels in Al Ain, UAE. Materials and Methods: We collected ticks, extracted, and sequenced RNA, using Illumina (NovaSeq 6000) and Oxford Nanopore (MinION). Results: From the total generated sequencing reads, 180,559 (~0.35%) and 197,801 (~0.34%) reads were identified as virus-related reads in male and female tick samples, respectively. Taxonomic assignment of the viral sequencing reads was accomplished based on bioinformatic analyses. Further, viral reads were classified into 39 viral families. Poxiviridae, Phycodnaviridae, Phenuiviridae, Mimiviridae, and Polydnaviridae were the most abundant families in the tick viromes. Notably, we assembled the genomes of three RNA viruses, which were placed by phylogenetic analyses in clades that included the Bole tick virus. Conclusion: Overall, this study attempts to elucidate the RNA virome of ticks associated with camels in the UAE and the results obtained from this study improve the knowledge of the diversity of viruses in H. dromedarii ticks. Keywords: camels, Hyalomma dromedarii, nanopore technology, UAE, viral diversity, virome analysis, whole genome sequencing.

Ticks Infesting Dogs in Khyber Pakhtunkhwa, Pakistan: Detailed Epidemiological and Molecular Report

Ticks and tick-borne diseases are considered a major challenge for human and animal health in tropical, sub-tropical, and temperate regions of the world. However, only scarce information is available on the characterization of tick species infesting dogs in Pakistan. In this study, we present a comprehensive report on the epidemiological and phylogenetic aspects of ticks infesting dogs in Pakistan using the mitochondrial markers i.e. Cytochrome c oxidase subunit 1 (cox1) and 16S ribosomal RNA (16S rRNA) nucleotide sequences. A total of 300 dogs were examined and 1150 ixodid ticks were collected across central Khyber Pakhtunkhwa, Pakistan. The morpho-molecular characterization of hard ticks revealed the presence of two ixodid tick genera on dogs, i.e., Hyalomma and Rhipicephalus, including six tick species viz. Hyalomma dromedarii (15.9%), Hyalomma excavatum (3%), Rhipicephalus sanguineus s.l. (41.3%), Rhipicephalus turanicus s.s. (28.7%), Rhipicephalus haemaphysaloides (10.2%), and Rhipicephalus microplus (2%). The total prevalence of tick infestation in dogs was 61%. The district with the highest tick prevalence rate in dogs was Mardan (14.7%), followed by Peshawar (13%), Swabi (12%), Charsadda (11%), and Malakand (10.3%), respectively. Risk factors analysis indicated that some demographic and host management-associated factors such as host age, breed, exposure to acaricides treatment, and previous tick infestation history were associated with a higher risk of tick infestation on dogs. This is the first molecular report confirming the infestation of Hyalomma and Rhipicephalus tick species in the dog population from the study area. The present study also reported a new tick−host association between Hy. excavatum, Hy. dromedarii, and dogs. Phylogenetic analysis revealed that cox1 partial nucleotide sequences of Hy. excavatum in our dataset were 100% identical to similar tick specimens identified in Turkey, and those of Hy. dromedarii were identical to tick specimens from Iran. Whereas, Rh. haemaphysaloides and Rh. microplus’ cox1 partial nucleotide sequences were identical to sequences previously published from Pakistan. Rhipicephalus turanicus s.s. ‘s cox1 isolates from the present study were 99.8−100% identical to Pakistani-reported isolates, and those of Rh. sanguineus s.l. were 100% identical to Chinese specimens. Results on the genetic characterization of ticks were further confirmed by 16S rRNA partial nucleotide sequences analysis, which revealed 100% identity between the tick isolates of this study and those of Hy. excavatum reported from Turkey; Hy. dromedarii specimens reported from Senegal; Rh. haemaphysaloides, Rh. microplus, and Rh. turanicus s.s., previously published from Pakistan, and Rh. sanguineus s.l., published from China. Furthermore, phylogenetic analysis showed that the Rh. sanguineus s.l. isolates of this study clustered with specimens of the tropical lineage with 7.7−10% nucleotide divergence from the specimens of the temperate lineage. Further molecular works need to be performed throughout Pakistan to present a more detailed map of tick distribution with information about dog host associations, biological characteristics, and pathogen competence.

Crimean–Congo hemorrhagic fever in the Arab world: A systematic review

Crimean-Congo hemorrhagic fever (CCHF) is an important tick-borne viral infection with a fatality rate of up to 50% during outbreaks. Crimean-Congo hemorrhagic fever virus (CCHFV) is sustained in the ecosystem in benign form through vertical and horizontal transmission cycles involving tick vectors, wildlife, and livestock. Hyalomma ticks are considered the major source of human infection. CCHF occurs most often among butchers, slaughterhouse workers, and farmworkers through infected tick bites or/and contact with blood and tissues of infected livestock. The nosocomial transmission can occur in auxiliary nurses and physicians through contact with the infected patients. The widespread distribution of CCHFV most probably occurred by ticks on migratory birds, or through international travel and trade of livestock and wildlife. During co-infections of ticks and vertebrates, reassortment among genome segments could play a significant role in generating diversity, and hence, a potential risk for the emergence of novel variants. In this systematic review, we aimed to determine the epidemiology, transmission, distribution, mortality, and clinical features of CCHF in 22 Arab countries, comprising the Arab world. Based on the analysis of 57 studies published from 1978 to 2021, we found 20 tick species that could be associated with CCHFV transmission. During the 43-year period, 321 cases of CCHF were reported from 9/22 Arab countries, Iraq, Kuwait, UAE, Saudi Arabia, Oman, Sudan, Egypt, Tunisia, and Mauritania. The mean case fatality rate was 29% during various outbreaks. Individuals working in abattoirs/slaughter houses, livestock farms, and healthcare were most at risk. Contact with blood or body secretions from infected animals and patients was the most common mode of transmission. A number of different animals, including cattle, goats, sheep, and camels were reported to be seropositive for CCHFV. The highest seroprevalence was observed in camels (29%), followed by cattle (21%), goats (15%), and sheep (14%). We discuss these results in the context of policy-making and potential preventative measures that can be implemented to reduce the burden of CCHF in the Arab world.

Assessing Temporal Changes in Microbial Communities in Hyalomma dromedarii Collected From Camels in the UAE Using High-Throughput Sequencing

Ticks (Acari) are ectoparasites of animals that harbor communities of microbes of importance to animal and human health. Microbial communities associated with ticks exhibit temporal patterns of variation in their composition, with different genera dominating at different times of the year. In this study, molecular tools were used to assess the composition of the microbial communities associated with Hyalomma dromdarii. Adult ticks were collected every month for 1 year from 25 camels in the UAE. A total of 12 DNA pools were prepared (one pool for each month). We monitored the microbiota of ticks using high-throughput sequencing of the V3–V4 region of the bacterial 16S rRNA gene. A total of 614 operational taxonomic units were produced through de novo clustering and belonged to 17 phyla, 30 classes, 46 orders, 118 families, and 222 genera. Fifteen bacterial families were found to be the most abundant. The dominant bacterial communities associated with H. dromedarii belonged to the genera Staphylococcus, Bacillus, Francisella, and Corynebacterium, which were reported with high relative abundance from all months. No significant correlation occurred between the abundance of microbial families or genera in H. dromedarii ticks and the ambient temperature. Our findings revealed, for the first time in the UAE, temporal fluctuations of microbial communities in H. dromedarii ticks and provided key insights on the interaction between different microbial groups. Moreover, our results contribute to the current understanding of disease development and allow more investigations for potentially pathogenic microbiota.