Seasonal Variations in the Microbiome of Hyalomma excavatum Ticks in Algeria.

Ticks are key vectors of zoonotic diseases, with their microbiomes playing a critical role in tick physiology, survival, and vector competence. This study presents the first investigation of the microbiome in Hyalomma excavatum ticks from Algeria, focusing on seasonal variations in bacterial diversity, community composition, and pathogen interactions. Using next-generation sequencing (NGS), the microbiome of 21 female ticks collected during spring, summer, and autumn was analyzed. Beta diversity analysis revealed significant seasonal shifts in microbial community structure, while alpha diversity metrics showed no significant differences in richness and evenness. Co-occurrence network analysis demonstrated seasonal shifts in microbial interactions, particularly between symbionts and pathogens, highlighting Francisella as a key taxon in tick survival and pathogen dynamics. Rickettsia presence varied by season, influencing microbial network stability. These findings underscore the ecological determinants shaping the microbiome and its potential role in pathogen transmission. Understanding seasonal microbiome shifts provides valuable insights for managing tick-borne diseases and could inform the development of targeted, season-specific vector control strategies.