extraction-saliva-haemolymph-salivary-glands-midgut-from-individual

Extraction of Saliva, Haemolymph, Salivary Glands, and Midgut from Individual Ticks (Acari: Ixodidae)

Ticks are blood-feeding ectoparasites recognised for their ability to transmit several infectious pathogens to humans and animals. Tick-borne pathogen ...

International Centre of Insect Physiology and Ecology (icipe)

University of Pretoria

university of khartoum

Tick-borne pathogen (TBP) surveillance studies often use whole-tick homogenates when inferring tick-pathogen associations. However, localized TBP infections within tick tissues (saliva, hemolymph, salivary glands, and midgut) can inform pathogen transmission mechanisms and are key to disentangling pathogen detection from vector competence.

Tissue-specific localization of tick-borne pathogens in ticks collected from camels in Kenya: insights into vector competence.

 ()-infected livestock and wildlife have been epidemiologically linked to human Q fever outbreaks. Despite this growing zoonotic threat, knowledge of coxiellosis in wild animals remains limited, and studies to understand their epidemiologic role are needed. In -endemic areas, ticks have been reported to harbor and spread  and may serve as indicators of risk of infection in wild animal habitats. Therefore, the aim of this study was to compare molecular techniques for detecting  DNA in ticks.

Comparison of test performance of a conventional PCR and two field-friendly tests to detect  DNA in ticks using Bayesian latent class analysis.

Ticks are blood-feeding ectoparasites that harbor diverse pathogens and endosymbionts. Their microbial communities vary based on tick species, stage, sex, geographical location, surrounding environment, and tissue type. Understanding tick microbiota at the tissue level is crucial for unraveling how microbiomes are distributed in tick tissues and influence pathogen transmission. We used V1-V2 16 S rRNA gene sequencing to analyze tissue-specific bacterial compositions (hemolymph, saliva, salivary glands, and midgut) of Amblyomma gemma, Rhipicephalus pulchellus, Hyalomma dromedarii, and Hyalomma rufipes ticks collected from camels in Marsabit County, northern Kenya. The V1-V2 region of the 16 S rRNA gene effectively differentiated 43 Rickettsia africae and 16 Rickettsia aeschlimannii tick samples from other rickettsial species, as well as Coxiella endosymbionts from Coxiella burnetii. In contrast, the V3-V4 region sequences of these species could not be clearly distinguished. Coxiella endosymbionts were most common in Am. gemma and Rh. pulchellus, while Francisella endosymbionts predominated in Hyalomma ticks; both were primarily localized in the salivary glands. High abundances of Coxiella endosymbionts, as well as Pseudomonas, were associated with the absence or low abundance of Rickettsia pathogens in both Am. gemma and Rh. pulchellus, suggesting competitive interactions between these microbes. Additionally, Proteus mirabilis, an opportunistic pathogen of the urinary tract in humans, was found predominantly in Hyalomma ticks, except for the salivary glands, which were most abundant with Francisella endosymbionts. Furthermore, we detected the Acinetobacter, Pseudomonas, and Corynebacterium genera in all the tick tissues, supporting the hypothesis that these bacteria might circulate between camel blood and ticks. Saliva and hemolymph generally harbored more extracellular bacteria than the salivary glands and midgut. This study provides a new approach to unravel tick-endosymbiont-pathogen interactions by examining the tissue localization of tick-borne pathogens and symbionts in Am. gemma, Rh. pulchellus, Hy. dromedarii, and Hy. rufipes from camels in northern Kenya. Our findings establish a baseline for developing an understanding of the functional capacities of symbionts and for designing symbiont-based control strategies.

Exploring the microbiomes of camel ticks to infer vector competence: insights from tissue-level symbiont-pathogen relationships.

Ticks pose a major threat to livestock and human health in sub-Saharan Africa, with climate change and pastoral movements fueling their spread. Few studies have integrated multiple sample types to characterize tick-borne pathogens (TBPs) in cattle in Kenya. This knowledge gap hinders the development of effective surveillance and control strategies, leaving vulnerable populations and their livestock susceptible to these persistent threats.

Article	Year
Tissue-specific localization of tick-borne pathogens in ticks collected from camels in Kenya: insights into vector competence. Frontiers in cellular and infection microbiology\| PubMed ID: 38698904	2024
Comparison of test performance of a conventional PCR and two field-friendly tests to detect DNA in ticks using Bayesian latent class analysis. Frontiers in veterinary science\| PubMed ID: 38962707	2024
Exploring the microbiomes of camel ticks to infer vector competence: insights from tissue-level symbiont-pathogen relationships. Scientific reports\| PubMed ID: 39955302	2025
Molecular characterisation of tick-borne pathogens in cattle in kenya: insights from blood, ticks, and skin swab analyses. BMC veterinary research\| PubMed ID: 41039537	2025

Rua Khogali

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