Distribution of Phlebotomine Sandflies in the Cave Area of Satun Province, Thailand

Abstract

Leishmaniasis, a sandfly-transmitted protozoan infection, is a neglected health threat in Thailand and the information on its vector is scarce. This study aimed to identify sandfly distribution, abundance, and environmental conditions of natural breeding sites in the cave areas of Satun Province, where previous cases of leishmaniasis were reported. Sandflies were collected during a six-month period using CDC light traps and modified emergence traps. Species distribution, relative abundance, and environmental conditions of potential breeding sites were determined. Our survey of 12,790 sandflies found the highest female abundance in April–May. We identified six known species, the most prevalent being Sergentomyia anodontis. We also found S. barraudi, a potential Leishmania spp. vector, distributing in this area. Most male sandflies had partially rotated genitalia, indicating the breeding site proximity to our trap locations. Potential resting/breeding sites were discovered outside the cave during February–March, and inside during May–June. The environmental parameters showed warm climate, moderate humidity, moderately alkaline pH, moderate-to-high macronutrients, and low-to-high organic matters. In summary, our study provided the spatiotemporal distribution and environmental condition of sandfly potential breeding sites in the cave areas of Satun Province. This data may contribute to more effective vector surveillance programs in the future.

Phlebotomine sand flies (Diptera: Psychodidae) and sand fly-borne pathogens in the Greater Mekong Subregion: a systematic review

“…However, the occurrence of these species in a Previously listed as Phlebotomus in older publications humans and animals, as well as in the sand fly species identified, have all been previously reported in other studies in Thailand. The additional seven papers included one report on the detection of Bartonella in Vietnamese rodents [152], one on Vietnamese sand fly collections [153] and five on Thai sand fly collections [154][155][156][157][158]. In these seven papers, three new species of sand fly species were reported, including Sergentomyia rudnicki [154] (2 samples) and Phlebotomus papatasi [157] (16 samples) in Thailand, and Sergentomyia khawi [153] (27 samples) in Vietnam.…”

Determinants of cutaneous leishmaniasis among students in Delanta district, Northeast Ethiopia: A case–control study

“…Studies conducted in Brazil indicated as caves were important for the protection, feeding, and breeding of sand flies 39,40 . Another study conducted in Thailand also supported that caves are potential breeding sites for sand flies 41 . In addition, rocky territories have been identified as the preferred ecology of the vectors 42 …”

“…39,40 Another study conducted in Thailand also supported that caves are potential breeding sites for sand flies. 41 In addition, rocky territories have been identified as the preferred ecology of the vectors. 42 In this study, the likelihood of developing CL was four times conducted in Kenya 27 and Colombia.…”

Sand fly identification and screening for Leishmania spp. in six provinces of Thailand

“…Based on the morphological identification of female specimens, S. iyengari was the predominant species in several of the provinces investigated in this study, especially Chantaburi, Songkhla and Ubon Ratchathani provinces. The results of previous studies suggested that the species richness of sand flies in Thailand varied greatly among different provinces or habitats [ 19 , 32 – 36 ], possibly indicating that sand fly richness in Thailand might exhibit an area-specific distribution. These results indicated the need to investigate sand fly richness in several regions and habitats in order to obtain reliable information on sand fly species richness in Thailand.…”