Parasitologia

Tick-borne diseases are rising across Europe, yet human-biting tick data from the central Balkans remain limited. We analysed ticks removed from patients seeking care after tick bites at centers in Skopje (North Macedonia) and Novi Sad (Serbia) between January 2022 and December 2024, recording species, developmental stage, month of removal, and anatomical attachment site. A total of 1641 ticks were collected (North Macedonia, n = 157; Serbia, n = 1484) and identified morphologically. Six tick species were detected in North Macedonia and eight in Serbia. Ixodes ricinus was dominant in both countries, comprising ~69% of ticks in North Macedonia and >90% in Serbia, while Hyalomma marginatum was found in North Macedonia. Adult females predominated among ticks in North Macedonia (75.8%), whereas nymphs were most frequent among ticks in Serbia (55.6%); between-center comparisons of developmental stage should be interpreted cautiously given the marked sampling imbalance. In both settings, collections peaked in May–June (~64% of annual ticks), indicating highest bite pressure in late spring/early summer. Attachment sites were most commonly the torso and lower extremities, with significant between-country differences and species-/stage-specific patterns most evident in Serbia. These data refine the epidemiology of human tick exposure in two Balkan countries and support targeted seasonal prevention messaging and strengthened regional surveillance.

Horse flies (Tabanidae) negatively affect livestock by reducing productivity, compromising animal welfare, and serving as mechanical vectors of pathogens. However, the spatial processes shaping their community organization in southern Brazil’s Coastal Plain of Rio Grande do Sul (CPRS) remain poorly understood. To address this, we conducted standardized Malaise-trap surveys and combined them with historical–contemporary comparisons to examine distance–decay patterns in community composition. We evaluated both abundance-based (Bray–Curtis) and presence–absence (Jaccard) dissimilarities using candidate models. Across sites, Tabanus triangulum emerged as the dominant species. Dissimilarity in community structure increased monotonically with geographic distance, with no evidence of abrupt thresholds. The square-root model provided the best fit for abundance-based data, whereas a linear model best described presence–absence patterns, reflecting dispersal limitation and environmental filtering across a heterogeneous coastal landscape. Sites within riparian forests and conservation units displayed higher diversity, emphasizing the ecological role of protected habitats and the importance of maintaining connected corridors. Collectively, these findings establish a process-based framework for surveillance and landscape management strategies to mitigate vector, host contact. Future directions include integrating remote sensing and host distribution, applying predictive validation across temporal scales.

Entomopathogenic fungi are promising alternatives to synthetic insecticides for the control of vector species, notably the arbovirus vector, Aedes aegypti. The influence of intrinsic mosquito midgut microbiota on host susceptibility to fungal infection and subsequent physiological processes remains poorly understood. Here we treated female Ae. aegypti with the broad-spectrum antibiotic carbenicillin to reduce gut bacterial populations, then exposed them to Metarhizium anisopliae conidia. Female Ae. aegypti offered carbenicillin and then sprayed with fungi had significantly lower survival rates (38.9% ± 1.15) compared to non-antibiotic-treated mosquitoes sprayed with fungus (68.9% ± 0.58). To monitor the kinetics of microbial community recovery, mosquitoes were challenged with conidia at 0, 3, 6, and 9 days following antibiotic removal from the diet. Reduced survival persisted through the 6-day period (survival rates 37.8% to 45.6%), with a significant increase in survival observed 9 days post-antibiotic removal (58.9% vs. control 63.3%), which coincided with recovery of gut bacterial populations. Additionally, antibiotic and fungal treatments reduced egg production, larval eclosion, and pupal formation. These results demonstrate that gut bacteria contribute to mosquito defense against fungal pathogens and support normal reproductive and developmental functions. Understanding the interplay between gut microbiota and entomopathogenic fungi may enhance biological control approaches.