Despite their medical importance, natural breeding sites of sand flies have been poorly explored. Detecting such sites is imperative in vector control strategies. This study aimed to identify potential breeding and resting microhabitats of sand flies and household risk factors associated with cutaneous leishmaniasis transmission in Dir districts, Khyber Pakhtunkhwa, Pakistan. Survey of indoor and outdoor habitats in four tehsils (subdistricts) of upper and lower Dir districts was carried out using sticky traps, flit method, and aspirator. To assess risk factors associated with cutaneous leishmaniasis (CL), questionnaires were administered to household heads. Mud houses and plants belonging to Cucurbitaceae family sheltered highest number of sand flies. Excessive number of flies were collected from indoor sites (common rooms used for both people and animals) compared to outdoor habitats (cattle dungs). Phlebotomus salangensis Artemiev, 1978 and Phlebotomus sergenti were the most widely distributed species, while Sergentomyia bailyi peaked in caves with high organic content in soil. Roof material and ownership of fans were associated with significant risk of CL. Findings of this study present a list of potential breeding sites for sand flies and CL risk factors that can be targeted and implemented in control programs for CL. Further studies are required to elucidate the breeding behavior and preferences of these medically important vectors.

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The species composition, distribution, and bionomics of sand flies was investigated from January to December 2017 in four tehsils (20 villages) of district Bajaur (formally Bajaur agency), Khyber Pakhtunkhwa, Pakistan. In total, 4,173 adult specimens comprising of seven species of Phlebotomus (Diptera: Psychodidae) and three species of Sergentomyia (Diptera: Psychodidae) were collected by oral aspirator, insecticide spray, and sticky traps from June to October. Highest numbers of flies were collected indoors in July and August when relative humidity and temperature were highest. Phlebotomus sergenti Parrot (Diptera: Psychodidae) was the most abundant species from all the collection sites, making approximately 70% of the total capture. Combined dwellings and chicken cages harbored the highest number of adult and immature flies (unrotated external genitalia). Abundance of P. sergenti had a significant (P ≤ 0.05) positive correlation with monthly average temperature, relative humidity, and average rainfall in indoor collections. On the other hand, P. papatasi Scopoli displayed similar correlation in the indoor and nighttime collections. Both the species were apparently abundant in the elevation range ≤ 419 m above sea level and on rangelands. Phlebotomus papatasi, however, also occurred on agricultural lands. The number of cutaneous leishmaniasis (CL) cases did not significantly correlate with the abundance of sand fly vectors across the villages surveyed. The results reported herein can serve as a baseline for an all-extensive future work in Bajaur. Our investigations will benefit the public health experts and medical entomologists for improved control and surveillance vectors of leishmaniasis.

Present study was carried to determine the sand fly species composition, breeding sites ecology, seasonal abundance, and spatial distribution in district Malakand, Khyber Pakhtunkhwa, Pakistan. In addition, risk factors associated with cutaneous leishmaniasis (CL) were also evaluated. Survey of indoor and outdoor habitats was carried out using sticky traps in 31 villages of Dargai and Batkhela tehsils of Malakand.Soil from habitats of adult and immature sand flies was analysed. Questionnaire-based household survey was also performed in these villages to assess risk factors associated with CL. Soil samples from selected CL positive households were analysed for its contents. Additionally, clinicoepidemiological data from local health centres was examined for the year 2019. Total of 3,140 sand flies belonging to 18 species were collected. Phlebotomus sergenti was the most abundant species (38.16%). Its abundance had a strong positive correlation with mean monthly relative humidity and negative correlation with average temperature. Phlebotomus sergenti and Phlebotomus papatasi were abundant at an elevation ranging from 320 to 1,120 m above sea level and in agricultural lands near human settlements. Flight height preference apparatus collected maximum sand flies at 30 cm (1ft) above the ground and all species associated negatively with height. Soil analysis from habitats of adult and immature flies showed that highest mean number of adults and immatures were recorded from silt loam which carried highest concentrations of K 2 O, Mg, Ca, and Zn. Number of immature sand flies correlated moderately (r = .7, p < .05) with K 2 O soil concentrations. There was significant similarity between organic matter contents in soil samples from positive breeding sites and CL households (Wilcoxon rank-sum test, p = .1976). In multivariate analysis model for CL risk factors, age (26-35 and >35 years), knowledge of leishmaniasis, living in a middle and upper class, preachers visit to villages, and assumption that Afghan refugees are more prone to CL were significant. CL patient's archived data from health centres showed that majority of patients had lesions on face and hands. Patient's influx was highest in February and March.

We provide a comprehensive and updated review on the effects of elevation and climatic factors on distribution of sand fly (Diptera: Psychodidae) vectors of cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) across Pakistan. Our study was undertaken in view of the increasing risk of leishmaniasis, particularly resulting from climatic deviations and political instability in the region. Literature (published and unpublished) on suspected vectors of CL (Phlebotomus sergenti Parrot and Phlebotomus papatasi Scopoli) and VL (Phlebotomus major Yakimoff and Schokhor and Phlebotomus hindustanicus Theodor) was collected, sorted, and utilized in geospatial analysis. P. papatasi and P. sergenti co-occurred in majority of the referenced localities and were generally distributed toward the western and southern parts across a wide range of elevation, whereas P. major and P. hindustanicus were limited to high elevation in cool and humid northern areas of Pakistan. Conversely P. papatasi and P. sergenti exploited diverse ecological settings across the country, being particularly abundant in warm/hot and arid regions.