Variability of Cutaneous Leishmaniasis Lesions Is Not Associated with Genetic Diversity of Leishmania tropica in Khyber Pakhtunkhwa Province of Pakistan

Abstract

is the causative agent of cutaneous leishmaniasis in Pakistan. Here, intraspecific diversity of from northern Pakistan was investigated using multilocus microsatellite typing. Fourteen polymorphic microsatellite markers were typed in 34 recently collected isolates from Pakistan along with 158 archival strains of diverse Afro-Eurasian origins. Previously published profiles for 145 strains of originating from different regions of Africa, Central Asia, Iran, and Middle East were included for comparison. Six consistently well-supported genetic groups were resolved: 1) Asia, 2) Morroco A, 3) Namibia and Kenya A, 4) Kenya B/Tunisia and Galilee, 5) Morocco B, and 6) Middle East. Strains from northern Pakistan were assigned to Asian cluster except for three that were placed in a geographically distant genetic group; Morocco A. Lesion variability among these Pakistani strains was not associated with specific genetic profile. Pakistani strains showed little genetic differentiation from strains of Iraq, Afghanistan, and Syria (F = 0.00-0.06); displayed evidence of modest genetic flow with India (F = 0.14). Furthermore, genetic structuring within these isolates was not geographically defined. Pak-Afghan cluster was in significant linkage disequilibrium (I = 1.43), had low genetic diversity, and displayed comparatively higher heterozygosity (F = -0.62). Patterns of genetic diversity observed suggest dominance of a minimally diverse clonal lineage within northern Pakistan. This is surprising as a wide clinical spectrum was observed in patients, suggesting the importance of host and other factors. Further genotyping studies of isolates displaying different clinical phenotypes are required to validate this potentially important observation.

Characterization of sand fly breeding sites in district Malakand, Khyber Pakhtunkhwa, Pakistan, and evaluation of risk factors for cutaneous leishmaniasis in the region

“…Adult sand flies were collected on monthly and weekly basis. Monthly collections were made to define sand fly seasonal abundance (Khan, Llewellyn, et al, 2017) in the region, while weekly collections were performed to detect potential breeding sites (Wahid et al, 2020). Monthly collections were carried out in six indoor sites (including buffalo shed, cow shed, goat shed, sheep shed, cattle shed, and domestic household) from June to September 2019.…”

“…Both monthly and weekly collections were conducted through sticky traps (A4 size white printing pages meshed on both sides with castor oil) placed in selected sites at 7 p.m. and collected the next day at 7 a.m. (Figure 2a). Compared with other collection methods, sticky traps are reportedly effective in exploring species composition, seasonal abundance, probable natural breeding sites, and for its ease of use in night times collection (Akhoundi et al, 2012;Ali et al, 2016;Khan, Llewellyn, et al, 2017).…”

“…Immature male sand flies were identified on the basis of their unrotated external genitalia (Khan, Llewellyn, et al, 2017;Moncaz et al, 2012b;Wahid et al, 2020).…”

“…In Pakistan, CL is usually restricted to poverty-stricken and neglected areas (Kassi et al, 2008;Khan, Llewellyn, et al, 2017).…”

“…Identifying risk factors for leishmaniasis has key importance in designing community level response towards managing the disease (Khan, Llewellyn, et al, 2017). These factors may be modified to control and prevent future outbreaks.…”