The International Graduate Program of Veterinary Science and Technology (VST), Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand.
Department of Pathology, Faculty of Veterinary Science, Center of Excellence in Veterinary Parasitology, Chulalongkorn University, Bangkok, 10330, Thailand.
Parasit Vectors. 2024 Oct 29;17(1):443. doi: 10.1186/s13071-024-06509-w.
Sand flies, belonging to the Psychodidae family, represent small, hairy insects that serve as significant vectors in various important medical and veterinary diseases. Despite being recognized by the World Health Organization as an endemic area for leishmaniasis, Southeast Asia lacks comprehensive information on the species composition and biology of sand flies. To address this, the current study aimed to survey sand fly biodiversity.
Sand flies from six provinces in Southern Vietnam were collected using CDC light traps. Sand flies were subsequently identified morphologically and confirmed molecularly using mitochondrial cytochrome oxidase c subunit I (COI) and cytochrome b (cytb) sequences. BLASTN searches were conducted, and the species identity of sand flies was further confirmed through a Barcode of Life Database (BOLD) search utilizing COI sequences. Subsequently, nucleotide sequences were subjected to a panel of analyses including intraspecific variation, phylogenetic relationships and haplotype network. The average densities of collected sand flies (sand flies/trap/night) and species richness were also recorded.
A total of 753 sand flies were collected. After excluding damaged specimens, six sand fly species, namely Phlebotomus stantoni, Sergentomyia khawi, Se. silvatica, Se. barraudi, Se. bailyi and Grassomyia indica, were identified. All conspecific sand fly sequences, including Ph. stantoni, Se. barraudi, Gr. indica, Se. bailyi, Se. khawi and Se. silvatica, clustered with their reference sequences, corroborating the results of morphology-based identification, BLASTN analysis and BOLD search. For intraspecific variation of sand flies obtained from the current study, COI diversity indices were consistently higher than those of cytb.
This study provides the first updates on morphological and molecular characterization of sand flies in Southern Vietnam. This acquired knowledge on sand fly species composition is essential for controlling sand fly-borne diseases in this potentially endemic region.
沙蝇属于双翅目长角亚目，是一类小型多毛昆虫，是多种重要医学和兽医疾病的重要媒介。尽管东南亚被世界卫生组织确认为利什曼病的地方性流行区，但该地区缺乏有关沙蝇物种组成和生物学的全面信息。为了解决这一问题，本研究旨在调查沙蝇生物多样性。
采用美国疾病控制与预防中心的诱蚊灯在越南南部的六个省份采集沙蝇。随后，通过线粒体细胞色素氧化酶 c 亚基 I（COI）和细胞色素 b（cytb）序列的形态学和分子鉴定来识别沙蝇。进行 BLASTN 搜索，并通过利用 COI 序列的生命数据库（BOLD）搜索进一步确认沙蝇的物种身份。随后，对核苷酸序列进行了一系列分析，包括种内变异、系统发育关系和单倍型网络。还记录了收集的沙蝇的平均密度（每诱蚊灯/夜的沙蝇数量）和物种丰富度。
共采集到 753 只沙蝇。在排除受损标本后，鉴定出 6 种沙蝇，即 Phlebotomus stantoni、Sergentomyia khawi、Se. silvatica、Se. barraudi、Se. bailyi 和 Grassomyia indica。所有同种沙蝇序列，包括 Ph. stantoni、Se. barraudi、Gr. indica、Se. bailyi、Se. khawi 和 Se. silvatica，都与它们的参考序列聚类，这与基于形态学的鉴定、BLASTN 分析和 BOLD 搜索的结果一致。对于从本研究中获得的沙蝇种内变异，COI 多样性指数始终高于 cytb。
本研究首次更新了越南南部沙蝇的形态学和分子特征。获得的沙蝇物种组成知识对于控制该潜在地方性流行区的沙蝇传播疾病至关重要。
