Abstract:
Cutaneous Leishmaniasis (CL)is an endemic vector-borne disease in Sri Lanka.It is caused by
protozoan parasite Leishmania species and transmitted via infective bite of female
Phlebotomine sand flies (Diptera: Psychodidae). The public health importance of this disease
is positively increasing due to inadequate knowledge of vector biology. The current study is an
attempt to uncover the vector biological aspects, focusing on the successful vector control
interventions.
This study was carried out in Anuradhapura district, Sri Lanka; a district with high disease
prevalence of CL. Three sampling localities were selected; Thalawa, Padawiya and Wijayapura.
A questioner and field studies were carried out in the sampling areas among CL patients to
assess the effect of domestic environment characteristics on colonization of phlebotomine sand
flies. Presence of decaying garbage, termite hills, manna grass (Glyceria sp.), water streams,
unclear areas, wet soil areas, scrub jungles and gardening areas are the concerned characteristics
for the present study. Field studies were conducted every month for seven months continuously.
In every visit, Phlebotomine sand fly samples were collected from the study sites mentioned
above using yellow sticky trap method.
Increment of the mean number of sand fly population alongwith the increment of the number
of domestic characteristics was tested with the regression analysis.With the increment of
supportive environmental characteristics, sand fly populations were increased linearly (P =
0.000) in each site. This relationship revealed that the maximum sand fly populations were
recorded in the places with all the tested characteristics stated above. Accordingly, the
surrounding characteristics of the domestic environment have a significant effect on the
colonization of sand fly populations. Domestic characteristics such as decaying organic matter,
wet soil, unclear areas and water streams around the living environment show higher
contribution to the colonization of sand flies.
In conclusion, characteristics of the domestic environments have effect on the colonization of
sand flies. Increment of the supportive domestic characters intensifies the colonization of sand
flies.