Bionomics of the unexplored sand flies fauna of District Mohmand, Khyber Pakhtunkhwa, Pakistan: assessing risk factors associated with cutaneous leishmaniasis

Abstract

Background Sand flies are of considerable public health importance in Pakistan because these insects are vectors of leishmaniasis. The current study explores the bionomics of sand flies, their spatial distribution pattern and cutaneous leishmaniasis-associated risk factors in District Mohmand, Khyber Pakhtunkhwa, Pakistan. Methods Sand flies were collected from indoor and outdoor habitats in 69 villages of five tehsils in Mohmand during July–October 2019. Risk factor data were recorded for 829 households in 94 villages. Results In total, 2065 sand flies were captured. Phlebotomus (Paraphlebotbmus) sergenti was the most abundant species. Relative density for P. sergenti and Phlebotomus papatasi was highest in Prang Ghar and lowest in Safi. Sand flies abundance peaked in August and September, corresponding to maximum relative humidity, temperature and rainfall. Relative density for P. sergenti and P. papatasi was highest in combined dwellings (indoor) and cattle corrals (outdoor). Phlebotomus sergenti and P. papatasi were abundant at an elevation of 283–1140 m on agricultural land and rangelands. Both species were recorded abundantly on Carbontites, Mesozoic and Indus suture Melange rock formations. Presence of domestic animals, ownership of pet dogs, presence of muddy dunes in the village, knowledge of sandflies and use of mosquitoes spray remained significant risk factors. Conclusions The study reports sand fly bionomics in District Mohmand. Risk identified for cutaneous leishmaniasis are significant in strategising control methods for Health authorities can allocate localized control means to high-risk areas using these findings.

Epidemiology of cutaneous leishmaniasis in children of Khyber Pakhtunkhwa, Pakistan

“…The seasonal variation of sand flies can be an important factor in the transmission of cutaneous leishmaniasis. Meteorological changes generally shape the spread of leishmaniasis through changes in temperature and rainfall, which also affect the geographic distribution of sand fly populations [6,11,20,30].…”

“…The maximum number of cutaneous leishmaniasis cases were observed in male as compared to female children because males are usually involved in outdoor playing activities [6, 20, 30, 32]. The highest number of cases were recorded in children aged 5–9 years, as this group was most commonly affected in other studies [5, 6, 17, 33].…”

Distribution and Risk of Cutaneous Leishmaniasis in Khyber Pakhtunkhwa, Pakistan

“…Sandfly species of Phlebotomus and Sergentomyia genera are abundant in Khyber Pakhtunkhwa [ 56 , 57 , 58 , 59 , 60 ]. Although there have been no conclusive reports to clarify the pathogen-vector association between Leishmania and sandflies in Pakistan, Phlebotomus papatasi and Phlebotomus sergenti , the two most common species in several districts, are considered to be vectors of CL, while Phlebotomus major and Phlebotomus hindustanicus are suspected vectors of VL [ 56 ].…”

“…Phlebotomus caucasicus and Phlebotomus salehi were also indicated as potential vectors of CL in Middle East countries [ 64 , 65 , 66 ]. Other sandflies found in Khyber Pakhtunkhwa included Phlebotomus salengensis , Phlebotomus andrejevi , Phlebotomus kazeroni , Phlebotomus bergeroti , Phlebotomus ansari , Phlebotomus alexandri , Sergentomyia babu , Sergentomyia dentata , Sergentomyia baghdadis , Sergentomyia bailyi , Sergentomyia hospittii , Sergentomyia montana , Sergentomyia grekovi , Sergentomyia hodgsoni , Sergentomyia turkistnica , Sergentomyia tiberidis , Sergentomyia theodori , Sergentomyia sumbarica , Sergentomyia dreyfussi turkestanica , and Sergentomyia fallax afghanica [ 57 , 58 , 59 ]. On the other hand, records about reservoir hosts of CL are scarce in Pakistan.…”