Sandfly species diversity in association with human activities in the Kani tribe settlements of the Western Ghats, Thiruvananthapuram, Kerala, India

Abstract

Sandfly prevalence in the Kani tribe settlements of Western Ghats in India was investigated. A total of 1,279 sandflies comprising 17 species was obtained. Sandfly abundance showed a negative correlation (r = -0.97, p = 0.003) with increase in altitudinal ranges from 0-1,000 m. When sandfly samples were grouped according to landscape characteristics of the location, the estimated Shannon-Weiner index (H) and species richness index (S) were high and species evenness index (J) was low in settlements located at 0-300 m altitudinal range. On the contrary, the values of H and J were high, while S was low at 301-600 m altitudinal range. With further increase in altitude, species diversity, S and J were low. Though the relative abundance of sandflies decreased with increase in altitude, the influence of altitudinal variation could not be attributed to determine sandfly diversity, since the number of sampling units were not uniform at all the altitudinal gradients due to nonavailability of suitable resting shelters. Sandfly species showed great aggregation at 0-300 m altitude interval, where not only the number of settlements were maximum (n = 19), but also the environmental conditions favoured sandfly abundance due to the concentration of tribal settlements, human dwellings and his activities.

Leishmaniasis in Sri Lanka: spatial distribution and seasonal variations from 2009 to 2016

“…A previous study reported that P. argentipes is present at almost all altitudes in Sri Lanka [38]. However, this study shows that the highest incidence of leishmania patients was found less than 100 m above sea level.…”

“…Therefore, the environmental conditions in mountainous regions are unfavorable for the breeding and maturation of sand flies. In addition, lesser human activity on the environment at high altitudes minimizes the exposure of sand fly bites at high altitudes [38]. Similarly, studies in India and Turkey reported that the abundance of sand flies showed a negative correlation with an increase in altitude [43, 44].…”

Visceral Leishmaniasis in a Non-Endemic Region of India- Investigation of an Outbreak

“…Chempanaruvi is a small village located in the foothills of Western Ghats, geographically linked to places recently reported to have heavy infestations of sandflies. 6,7 Clinical examination and laboratory investigations and bone marrow biopsy were carried out for confirmation of diagnosis. Polymerase Chain Reaction (PCR) analysis was carried out at the Vector Control Research Centre (VCRC) at Kottayam, Kerala to characterise the parasite species involved in the infection.…”

“…2 Newer species of Phlebotomus and natural infection of Phlebotomus with Leishmania parasites have been demonstrated in the tribal belts of western ghats in south India in recent years. 6,7 Cutaneous and visceral forms of the disease have been detected in individuals with no history of travel to endemic areas and in whom no definite routes of transmission could be postulated. 2,7 Also, the clinical management of VL is undergoing rapid changes with the use of liposomal forms of Amphotericin B and also due to the use of various combinations of miltefosine, amphotericin B, paromomycin etc.…”

Avaliação dos perfis clínico, epidemiológico e imunológico da Leishmaniose Visceral em pacientes e cães sorotipos no município de Ipatinga - MG

“…LHV e umidade relativa, no período de 2011 a 2017. Outras publicações relacionaram períodos de maior umidade relativa à redução da prevalência de LHV, possivelmente ocasionados pelo deslocamento dos nichos de vetores pelas enxurradas no período das chuvas(RANGANATHAN et al, 2015;, geral e por provável aumento da carga parasitária(COSTA et al, 2013). O cruzamento de dados entre o grupo CCr e CAd e os grupos LCr e LAd também verificou que os grupos-controle possuíam uma média de eritrócitos estatisticamente maior que os grupos LAd e LCr, ressaltando como a doença altera a produção da série vermelha.…”