The monsoon-associated equine South African pointy mosquito 'Aedes caballus'; the first comprehensive record from southeastern Iran with a description of ecological, morphological, and molecular aspects.
Authors: Nejati Jalil, Azari-Hamidian Shahyad, Oshaghi Mohammad Ali, Vatandoost Hassan, White Vanessa L, Moosa-Kazemi Seyed H, Bueno-Marí Rubén, Hanafi-Bojd Ahmad A, Endersby-Harshman Nancy M, Axford Jason K, Karimian Fateh, Koosha Mona, Choubdar Nayyereh, Hoffmann Ary A
Journal: PloS one
Summary
# Editorial Summary: *Aedes caballus* Mosquito Surveillance in Southeastern Iran *Aedes caballus*, a vector capable of transmitting arboviruses to both humans and horses, has historically been recorded at surprisingly low densities in southeastern Iran despite environmental conditions favouring its establishment—a discrepancy prompting Nejati and colleagues to reassess its true prevalence in Sistan and Baluchistan Province. Using a multi-method approach combining four trap types deployed across fixed and variable sampling sites alongside molecular analysis (COI, ITS2, and ANT genetic markers), the researchers collected 1734 specimens predominantly via CO₂-baited bednet traps, with populations surging markedly after February rainfall events. Genetic sequencing revealed multiple haplotypes with modest COI divergence (0.89%) and ITS2 variation (1.6%), indicating that previous morphological misidentification likely classified many *Ae. caballus* specimens as the morphologically similar *Ae. vexans*, substantially underestimating the species' actual distribution and abundance. For equine professionals, these findings underscore the need for heightened awareness of arbovirus risk in this region and highlight how reliable vector identification—whether through updated morphological training or molecular confirmation—is essential for appropriate disease surveillance and control strategies. The seasonal pattern of increased abundance following rainfall offers a practical window for targeted vector management and client education around vector-borne disease risk during peak transmission periods.
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Practical Takeaways
- •Aedes caballus is a confirmed arbovirus vector in southeastern Iran with increasing abundance; equine practitioners in endemic regions should implement vector control measures and monitor for emerging arboviruses
- •Previous morphological identification challenges mean actual disease vector prevalence may have been underestimated; molecular confirmation is necessary for accurate epidemiological assessment
- •Seasonal rainfall patterns drive population spikes; targeted vector control should intensify during and after monsoon periods in affected regions
Key Findings
- •1,734 Aedes caballus specimens collected from southeastern Iran with majority captured by CO2-baited bednet traps
- •Notable population increase following February rainfall, indicating monsoon-associated abundance patterns
- •Molecular analysis identified multiple haplotypes with COI gene divergence at 0.89% and ITS2 divergence at 1.6%, suggesting previous morphological misidentifications with Ae. vexans