https://orcid.org/0000-0003-2938-4549
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Figures
Abstract
Ticks are the second most important vector of infectious diseases, after mosquitoes, and can transmit several diseases of concern for both human and veterinary health. This study molecularly barcoded ticks collected from goats in Pakistan and screened for associated pathogens. From July 2023 to June 2024, examination of 253 goats (Capra hircus) in the 7th district of Khyber Pakhtunkhwa found 170 goats infested with 1,305 ticks, equating to a mean abundance of 5.15 ticks per goat. A phenol-chloroform technique was used to extract DNA and subsequently amplify the presence of pathogen DNA targeting 16S, 18S gltA, and ompA genes. Tick DNA was also amplified for the molecular confirmation of species using 12S rDNA partial sequence. All collected ticks were identified morphologically and molecularly as Haemaphysalis Punctata (519), Hyalomma anatolicum (380), Hae. sulcata (269), and Hy. excavatum (137), including 361 females, 323 males, 286 larvae and 198 nymphs. This study detected several tick-borne pathogens including Colpodella spp., Ehrlichia spp. and Rickettsia hoogstraalii, as well as detecting the bacteria Providencia rettgeri. Rickettsia hoogstraalii was found in Haemaphysalis punctata collected from Karak District. In contrast, Hy. excavatum from Banuu district were found to carry P. rettgeri. Hyalomma excavatum infesting goats in Buner, Chitral, and Hy. anatolicum form Kohistan, District tested positive only for Colpodella spp. whereas a single species of uncultured Ehrlichia spp. was found in Hae. sulcata collected from Mansehra, and Lakki Marawat district. This research’s novel report of human pathogenic microbes detected in ticks has implications for livestock and human health, as well as the role ticks potentially play in zoonotic disease transmission in Pakistan.
Author summary
Ticks are well known for spreading diseases to humans and animals, yet the full range of pathogens they carry in many parts of the world—including Pakistan—remains poorly understood. In this study, we examined ticks collected from goats across seven districts of Khyber Pakhtunkhwa to better understand which species are present and what microbes they may transmit. Using both traditional identification and DNA sequencing, we found four common tick species and discovered several microorganisms of potential concern. These included Rickettsia hoogstraalii, Ehrlichia species, and Colpodella species—an emerging protozoan increasingly linked to human and animal infections. We also detected Providencia rettgeri, a bacterium typically associated with hospital acquired infections, marking the first time it has been reported in ticks. Although more research is needed to determine whether ticks can transmit these microbes to humans or livestock, our findings highlight the importance of continued surveillance in regions where people and animals live in close contact. This study provides new insight into the diversity of pathogens circulating in Pakistan’s tick populations and underscores the need for public health awareness and further investigation into their potential risks.
Citation: Ullah S, Sher H, Cossío-Bayúgar R, Giantsis IA, Haleem S, Niaz S, et al. (2026) First report of Providencia rettgeri, Colpodella spp., Ehrlichia spp., and Rickettsia hoogstraalii in ticks infesting goats of Pakistan. PLoS Negl Trop Dis 20(3): e0014060. https://doi.org/10.1371/journal.pntd.0014060
Editor: Jun Jiao, State Key Laboratory of Pathogen and Biosecurity, CHINA
Received: September 2, 2025; Accepted: February 19, 2026; Published: March 9, 2026
Copyright: © 2026 Ullah et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All sequences from this project are publicly available and listed on GenBank, with accession numbers available in text and can be found in Table 4.
Funding: This research was funded by Higher Education Commission (HEC) Pakistan’s National Research Program for Universities (NRPU), grant number 14905 (Awarded to SN). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of this manuscript.
Competing interests: The authors have declared no competing interests exist.
Introduction
Ticks are considered the most important hematophagous ectoparasite that feed incidentally on humans and are second only to mosquitoes as vectors of human diseases [1,2,3]. Out of the roughly 900 tick species that have been identified, ~ 700 are classified as hard ticks (Ixodidae), ~ 200 as soft ticks (Argasidae), and a single species described as a member of the Nuttalliellidae family [4], many of which carry and transmit tick-borne pathogens (TBPs).
Ticks from the Hyalomma genus are significant vectors of viruses, bacteria, and parasites, and are known to transmit Nairovirus, the causative agent of Crimean-Congo hemorrhagic fever in humans [5,6], Wad Medani virus, and Thogoto virus to name a few. Bacterial pathogens vectored by Hyalomma ticks include Ehrlichia, Anaplasma, Rickettsia, and Coxiella. They also play a key role in the transmission of parasitic pathogens such as Babesia ovis, [7,8,9,10]. Hyalomma excavatum [11] (Acari: Ixodidae)] parasitizes various domestic animals including dogs, sheep, goats, cattle, camels, and horses [11,12]. In addition to bacterial infections like rickettsiosis, Hy. excavatum also spreads protozoan diseases including babesiosis and theileriosis [13,14,15].
Viral infections such as Crimean Congo hemorrhagic fever have received more attention given the severity of disease and observed seasonal spikes coinciding with Eid al-Adha in Pakistan [16,17]. Moreover, anaplasmosis and 60 cases of Babisia were found in a nomadic goat herding community [18]
Rickettsia, an obligate intracellular Gram-negative bacterium, are primarily transmitted to vertebrates by hard ticks (Ixodidae) and include species with known human pathogenicity and others with unknown pathogenicity [19,20,21,22]. Multiple tick species have been shown to carry Rickettsia hoogstraalii in different parts of the world [Brown et al., 2016,19,23,24,Orkun et al., 2022,[19]. Of the thirteen species of Haemaphysalis ticks reported from Pakistan [24], Hae. sulcata is known to transmit Spotted Fever Group (SFG) rickettsia. Additionally, Hae. punctata and Hae. Sulcata have both been reported to transmit piroplasmosis to cattle, buffalo, sheep, and goats in Pakistan [25,26].
Colpodella spp., a free-living microorganism closely related to apicomplexan parasites, represents an evolutionary bridge between free-living protozoa and parasitic apicomplexans [27,28,18]. More recently, Colpodella spp. have been reported to infect vertebrates (e.g., Amur tiger, horse) and humans,which are thought to possibly be transmitted by infected Rhipicephalus microplus, Dermacentor everestianus, and D. nuttalli ticks [29,30,31]. Although little is currently known about the pathogenicity, vectoral capacity, and geographical distribution of Colpodella spp., they may pose an under-recognized public health risk [32,33].
Gram-negative Providencia rettgeri is an opportunistic pathogen that infects immunocompromised hosts and is associated with nosocomial urinary tract infections, traveler’s diarrhea, and severe illnesses. [34,35,36,37,38]. While P. rettgeri has been reported to infect humans and Drosophila melanogaster, [39], to our knowledge, no detection in ticks has been reported. To address important gaps in the epidemiology of ticks and tick-borne pathogens in northern Pakistan, this study aimed to morphologically and molecularly characterize ticks and their associated pathogens.
Materials and methods
Ethics statement
The study was approved by the ethical committee of the Faculty of Life and Chemical Science, Abdul Wali Khan University Mardan.
Study area
The study was carried out across seven districts in Khyber Pakhtunkhwa: Kohistan, Chitral, Bannu, Mansehra area, Buner, Karak, and Lakki Marwat. GPS data from these collection sites were gathered and used to create a distribution map of ticks using ArcGIS v. 10.3.1 (ESRI, Redlands, CA, USA), as illustrated in Fig 1.
Fig 1 was created in ArcGIS, and the base map shapefile was obtained from DIVA-GIS (https://diva-gis.org/download.html), which is openly available for use.
Tick collection and identification
Ticks were collected from July 2023 to June 2024, with all parts of the goats’ bodies examined for infestation. A total of 253 goats were searched, yielding 1,305 ticks. Most ticks were found in the inguinal, udder, inner surface of the thighs, and perianal and vulvar areas. After collection, distilled water was used to clean the tick specimens and were preserved in Eppendorf tubes containing 70% ethanol. These preserved specimens were then studied under a stereo-zoom microscope for morphological identification, using standard identification keys [40].
DNA extraction and PCR
Three ticks from each host, specifically one male, one female, and one nymph were used to extract DNA. Ticks were then cleaned by using distilled water and PBS. After cleaning, specimens were allowed to dry by incubating them 25–35 minutes at 37 °C. Each tick was first cut into small pieces using sterile surgical blades and then homogenized using mortar and pestle. Genomic DNA was extracted from the homogenized tick specimens using the conventional phenol-chloroform process according to the protocol of [41]. A NanoDrop spectrophotometer (Nano-Q, Optizen, Daejeon, South Korea) was used to determine the amount of extracted DNA.
Extracted DNA was amplified by PCR utilizing the 12S rDNA partial fragment for molecular identification of ticks and the gltA, ompA, and 16S rDNA, 18S rDNA markers for pathogens associated with ticks, as indicated in Table 1. The 25 µL PCR reaction mixture was prepared using 12.5 µL of Master mix (2×) (Thermo Fisher Scientific, Inc., Waltham, MA, USA), 8.5 µL of PCR water, 2 µL of genomic DNA template (100 ng/µL), and 1 µL of each primer (10 µM) for the forward and reverse. The positive control included Anaplasma capra DNA (already amplified in other studies conducted in our lab), R. massilliae gltA DNA, and Rh. microplus 12S DNA. The negative control was nuclease-free PCR water. After being run on a 2% agarose gel, the amplified PCR products were visualized using the GelDoc system (BioDoc-It Imaging Systems; Upland, CA, USA) and stained with ethidium bromide. Prior to sequencing, the amplicons were purified in both directions using the Invitrogen JetFlex DNA purification kit (Waltham, MA, USFompbA).
Sequencing and phylogenetic analysis
ABI Prism 310 Genetic Analyzer capillary sequencer (Applied Biosystems) was utilized to do a bidirectional sequencing of all positive PCR products of the expected size. FinchTV (version 1.4) was used to trim the acquired sequences in order to remove primer contamination and low sequencing reads. A single consensus sequence was generated from the forward and reverse sequences of each sample. Using GenBank as a source for comparison, similar sequences [42] with higher identity were found using the Basic Local Alignment Search Tool (BLASTn; National Centre for Biotechnology Information [NCBI]). The sequences were first trimmed using FinchTV (version 1.4.0) to remove primer-contaminated areas and any misread nucleotides at the beginning and end of sequences and aligned using the ClustalW algorithm in MEGA11 (Molecular Evolutionary Genetics Analysis). The maximum likelihood technique was employed to create separate phylogenetic trees for tick and pathogen sequences, with nodes subjected to a 1000-replicate bootstrap resampling process for improved accuracy.
Statistical analysis
All data related to tick infestation were inserted into MS Excel spreadsheet (version 2108). The data were then analyzed in Excel to calculate the total prevalence: (infested goat/total goat) × 100; the overall mean intensity: total ticks / infested goat; and the mean abundance: total ticks / total goat.
Results
Tick collection and infestation prevalence
A total of 253 goats (Capra hircus) were examined for tick infestation across various districts of Khyber Pakhtunkhwa, Pakistan. Ticks were collected from 170 goats, yielding a total of 1,305 ticks. This corresponds to an overall infestation prevalence of 67.2%. The mean number of ticks per infested goat was 7.7, and the overall mean abundance was calculated as 5.2 ticks per goat. Tick infestations were recorded year-round, with peak activity noted between May and October. District level data indicated that Buner had the highest number of ticks, followed by Kohistan, Chitral, Mansehra, Bannu, Karak, and Lakki Marwat (Fig 1).
The developmental stages of the ticks included 470 adult females, 375 adult males, 281 nymphs, and 179 larvae. The detailed distribution of tick stages by district is presented in Table 2. All collected ticks were morphologically identified as Hae. sulcate, Hae. punctata, Hy. anatolicum, and Hy. excavatum (Fig 2) by using an established key [40].
Hyalomma anatolicum female (A), Hyalomma anatolicum male (B), Hyalomma anatolicum male ventral side (C) Hyalomma excavatum female (D), Hyalomma excavatum female ventral side (E), Hyalomma excavatum male (F), Haemaphysalis sulcata female (G), Haemaphysalis sulcata female ventral side (H). Haemaphysalis sulcata male (I), Haemaphysalis sulcata male ventral side (j), Haemphysalis punctata male (K), Haemphysalis punctata male ventral side (L), Dorsal and ventral view of ticks collected from goats showing key morphological features.
Molecular screening and overall infection rate
Of the 1,305 collected ticks, 510 were selected for molecular screening using PCR. This subset consisted of 170 females, 170 males, and 170 nymphs. Out of these, 74 ticks tested positive for at least one pathogen, resulting in an overall infection rate of 5.67%. The screening revealed the presence of four main pathogens: Colpodella spp., uncultured Ehrlichia spp., R. hoogstraalii, and P. rettgeri. Female ticks exhibited a higher infection rate than males and nymphs, with 38 positive females compared to 26 males and 10 nymphs. This trend was consistent across most districts, suggesting a sex-related difference in pathogen carriage.
Pathogen detection
Molecular screening revealed the presence of multiple tick-borne pathogens, with Colpodella spp. being the most frequently detected. This protozoan was primarily found in Hy. excavatum collected from Buner and Kohistan, with prevalence rates of 8.98% (15/167) and 5.48% (9/164), respectively (Table 3). In Chitral, Colpodella spp. was also detected in Hy. anatolicum, where 8 of 100 ticks tested positive (8%). Uncultured Ehrlichia spp. was detected exclusively in Hae. sulcata, with 12 out of 176 ticks (6.81%) in Mansehra and 10 out of 93 ticks (10.75%) in Lakki Marwat testing positive, indicating the pathogen’s circulation in both regions. The highest pathogen prevalence observed in the study was in Karak, where Hae. punctata carried R. hoogstraalii at a rate of 14.28% (12/84), marking the district as a hotspot for rickettsial infections. In Bannu, Hy. excavatum was found to harbor P. rettgeri, with a prevalence of 5.83% (8/137), suggesting the emergence of this bacterium as a potential zoonotic agent.
Host-pathogen-tick associations summarized in Table 4 show that Hy. anatolicum from Buner, Chitral, and Kohistan was associated with Colpodella spp., Hae. punctata from Karak with R. hoogstraalii, Hae. sulcata from Mansehra and Lakki Marwat with Ehrlichia spp., and Hy. excavatum from Bannu with P. rettgeri. Overall, 74 out of 510 ticks (5.67%) tested positive, highlighting the complex and region-specific distribution of tick-borne pathogens and underscoring the importance of ongoing molecular surveillance to understand and mitigate potential zoonotic risks in livestock-rearing regions of Pakistan.
Ticks and pathogens DNA analysis
Haemaphysalis sulcata, Hae. punctata, Hy. anatolicum and Hy. excavatum ticks were used to extract DNA. All tick-related sequences, together with their pathogen, were uploaded to the NCBI's GenBank (Table 4). The Hae. sulcata 12S rDNA amplicons showed a 99–100% similarity range for 12S rDNA in the BLAST analysis's, with a percent identity of 99.15% with the Hae. sulcata partial 12S rDNA sequence from Algeria (KY511421), Hae punctata display 100% identity with Hae. punctata sequence from China (MN267437), Hy anatolicum display 100% identity with Hy. anatolicum sequence from Pakistan (OR911528) and Hy. excavatum displays 100% identity with Hy. excavatum reported from Turkey (MG418642).
BLAST analysis revelated the 16S rDNA sequence of the Colpodella spp. species isolated from Hy. anatolicum displayed a higher percent identity to other Colpodella spp. species reported in GenBank. Specifically, the species was found to have 100% identity and query cover with sequence Colpodella spp. (MH208621) isolated from Rhipicephalus haemaphysaloides in China, and 99.92% with Colpodella spp. (GQ411073.1) that isolated from woman in China with relapsing Babesia-like illness. Similarly, the sequence had a 99.59% identity to Colpodella spp. (MH012046.1) that isolated from Dermacentor nuttalli in China. The gltA amplified P. rettgeri yielded 99.04% to Providencia spp. from the urine of human in China, and 99.03% (CP076406) with a patient isolate from Argentina. The gltA amplified R. hoogstraalii showed 100% similarity (MF383601) with an isolate from Hae parva removed from a patient in Turkey, and 98.33% (KY570489) with an isolated from ticks in Greece, and uncultured rickettsia (MT502507) from South Korea. The Uncultured Ehrlichia spp. 16S (OR668794) shows 100% identity with (OP047595) Uncultured Ehrlichia spp. that was isolated from human in USA. Details on pathogens detected by district can be found in Table 4.
Phylogenetic analysis of tick sequences
In the current investigation, the haplotype grouped with the 12S sequence of Hae. sulcata that had previously been reported from Algeria, according to the evolutionary tree that was created by using 12S partial ribosomal DNA (KY511421). All 5 sequences of Hae. sulcata reported from this study clustered together with same number of nucleotide substitutions in the same clade. The Hae. punctata in this study grouped with the Hae. punctata 12S sequence that was previously published from China (MN247437). A number of Haemaphysalis spp. sequences were included in the phylogenetic tree as references. Additionally, Rh. microplus 12S sequence reported from buffaloes of Pakistan (MK578158) were used as an outgroup in the current tree as shown in Fig 3. The evolutionary tree inferred for the partial 12S partial ribosomal DNA of Hy. anatolicum in the current study revealed the study’s haplotype grouped with the Hy. anatolicum 12S sequence that had been reported from Pakistani goats (OR911528, OR665374). All 3 sequences of Hy. anatolicum reported from this study clustered together with same number of nucleotide substitutions in the same clade. The Hy. excavatum of the current study clustered together with the 12S sequence of Hy. excavatum previously reported from Turkey (MG418642). The other Hyalomma sequences were included in the phylogenetic tree as references. Similarly, the 12S sequence of D. variabilis reported from USA (OR665368) were used as an outgroup in the inferred tree as shown in Fig 4.
Phylogenetic analysis of pathogen sequences
The Maximum Likelihood inferred phylogenetic tree of Colpodella spp. produced several clades of the genus Colpodella spp. The current study’s haplotype grouped with similar species reported from Rh. haemaphysaloides in China (MH208621) and Colpodella spp. from woman with relapsing Babesia-like illness (GQ411073) in China. The Colpodella spp. sequence also clustered with Colpodella spp. that was detected in D. nuttalli in China (MH012046) as well as with an uncultured eukaryote from France (AY817009) as shown in Fig 5. The tree uses several other species in the same genus for referencing the current haplotype. All the Colpodella spp. were clustered with 99.8% ultra-fast bootstraps support values and a 97% approximate likelihood ratio iterated 1000 times. The R. hoogstraalii species reported from a tick in Greece (KY570489) used as an outgroup as shown in Fig 5.
Pathogens amplified using the 16S rDNA partial fragment sequence, 1000 bootstrap iterations, and the Kimura 2 parameter with Gamma distributions (+G).
The P. rettgeri phylogenetic tree was inferred using maximum likelihood method. The tree resulted in several clades of the P. rettgeri species. The current haplotype grouped with the same species P. rettgeri that reported from human in China (CP076405), (CP076406). The sequences also clustered with Providenica previously reported from human in China (CP042861). These clustered species had different nucleotide substitutions which likely presents the distinct genotype nature of the reported species shown in Fig 6. Providenica alcalifaciens species (OU659204) were used as an outgroup for referencing.
The highest likelihood approach was used to infer the evolutionary tree of R. hoogstraalii. The tree resulted in several clades of the R. hoogstraalii species. The current haplotype grouped with the same species R. hoogstraalii that reported from Hae. parva ticks (KY570489) and a patient (KY570486) in Greece, as shown in Fig 7, with A. capara from South Korea (LC432112) used as an outgroup for referencing.
The phylogenetic tree for uncultured Ehrlichia spp. was inferred using maximum likelihood method. The tree resulted in several clades of the uncultured Ehrlichia spp. The current haplotype grouped with the same species of uncultured Ehrlichia spp. that reported from Rh. microplus in China (OP047995), (OP047994). The sequences were also clustered with uncultured Ehrlichia spp. that previously reported from Hy. anatolicum in Pakistan (MH250197) as shown in Fig 8, using E. chaffeensis (CP000236) as an outgroup.
The Maximum Likelihood inferred phylogenetic tree of Colpodella spp. produced several clades of the genus Colpodella spp. The current study’s haplotype grouped with similar species reported from Rh. annulatus in Egypt (PP937594) and Colpodella spp. from (MH208620) in China. The Colpodella spp. sequence also clustered with Colpodella spp. as shown in Fig 9. The tree uses several other species in the same genus for referencing the current haplotype. All the Colpodella spp. were clustered with 99.8% ultra-fast bootstraps support values and a 97% approximate likelihood ratio iterated 1000 times. The Ehrlichia canis reported from tick in Israel (U26740) were used as an outgroup for referencing.
Pathogens amplified using the 18S rDNA partial fragment sequence, 1000 bootstrap iterations, and the Kimura 2 parameter with Gamma distributions (+G).
Discussion
This study highlights the significant burden of tick infestations and the associated risk of tick-borne pathogens (TBPs) in Pakistan, with implications for public health and livestock productivity. A high tick infestation prevalence (67.19%) was recorded in goats, with the Buner district showing the highest proportional infestation rate (77.19%). Morphological and molecular analyses identified four tick species (Hy. anatolicum, Hy. excavatum, Hae. sulcata, and Hae. punctata). Pathogen analysis revealed the presence of zoonotic agents such as R. hoogstraalii and novel or emerging pathogens like Colpodella spp. and P. rettgeri, marking the first potential detection of Colpodella spp. in Pakistan. Seasonal activity peaking from May to October further accentuates the risk of zoonotic disease transmission during these months.
The current study provides insights into the distinct pathogen profile of the various tick species infesting goats of Pakistan, including the detection of opportunistic pathogenic bacteria, P. rettgeri [43,44] was isolated from Hy. excavatum. Additionally, Colpodella spp., R. hoogstraalii and uncultured Ehrlichia spp., were also detected in Hy. anatolicum; Hae. sulcata, and Hae. punctata ticks.
Colpodella-like species have been recently reported as potential infectious agents and causes human infections [45,46], with the first human infection caused by Colpodella spp., through tick bites being reported in China in 2012 [47,48]. This emerging species, Colpodella spp., has previously been reported in Ixodes persulcatus, Rh. microplus, Rh. haemaphysaloides, Hae. longicornis, and Hy. dromedarii [31,32,49,50]. The findings of this study make a case for expanded surveillance of this microorganism in Hy. anatolicum ticks as a possible carrier of Colpodella spp. Additionally, monitoring atypical neurological symptoms following tick bites for possible Colpodella infection will help determine if this pathogen poses a risk to human populations in Pakistan.
Although R. hoogstraalii belongs to the SFG Rickettsia group, little information about its pathogenicity in vertebrates is currently available [51]. The first instance of isolation of R. hoogstraalii happened in 2006, from Hae. sulcata ticks infesting goats and lambs in Croatia. Hard ticks from both domestic and wild ruminants in Europe have also been shown to contain R. hoogstraalii. Ticks from various locations in Europe have been found to carry Rickettsia hoogstraalii, including Hae. punctata and Hae. sulcata from Sardinia, Italy and Spain; Hae. parva and Hae. sulcata from Greece, Hae. sulcata and Dermacentor marginatus from Georgia, and Hae. punctata from Cyprus [23,52,53,54]. It has also been found in soft tick species, in Ethiopia, Japan, Iran, Namibia, Zambia, China, and the United Arab Emirates [55,56,57,58,59,60,61]. Previous research has revealed that multiple species of Rickettsia have been found in Pakistan in ticks that infest a variety of hosts. However, very limited information about the presence and genetic characterization of R. hoogstraalii has been reported. Here we describe the first report of R. hoogstraalii detected in Hae. punctata in Pakistan. Further research should be done to assess the pathogenicity of R. hoogstraalii in mammals as well as the potential role of Hae. punctata as a competent vector of disease.
Limitations
This study provides the first molecular evidence of Colpodella spp., R. hoogstraalii, and P. rettgeri, in ticks infesting goats in Pakistan; however, several limitations must be acknowledged. First, due to the engorged status of some of the collected ticks, there is a possibility that the detected pathogens particularly P. rettgeri originated from the goat host's blood meal rather than representing true tick infections. This raises the concern of environmental or host-derived contamination, especially in the case of P. rettgeri, which is known to be an opportunistic pathogen in diverse environments. Second, the study utilized relatively short gene fragments (gltA and 16S rRNA) for pathogen detection and identification. While these markers are commonly used for preliminary screening, sequencing longer genomic regions or using whole-genome approaches in future studies would provide more robust taxonomic resolution and support for pathogen identification. We also acknowledge the need to determine what role, if any, ticks play in transmission of Coplodella spp. and P. rettgeri in Pakistan, which should include pathogen localization within tick tissues and experimental transmission studies.
Conclusions
In conclusion, this study adds to our understanding of pathogen diversity within common tick species infesting goats in Pakistan. The identification of P. rettgeri, Colpodella spp., and R. hoogstraalii underscores the importance of recognizing emerging and potentially zoonotic pathogens in local tick populations. The detection of Colpodella spp. in Hy. anatolicum ticks highlights the need for further investigation into the vector competence of ticks and the possible zoonotic transmission of this pathogen. Additionally, the first report of R. hoogstraalii in Hae. punctata from Pakistan represents a new data regarding its geographic distribution and potential tick vector. These findings underscore the urgency of conducting further research on the pathogenicity, transmission dynamics, and ecological factors influencing tick-borne diseases in Pakistan. The results of this study provide a critical foundation for future investigations into tick-borne pathogens and emphasize the necessity of continuous surveillance and public health efforts to mitigate the risks associated with emerging infectious diseases.
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