Dataset Information

Spatio-temporal distribution of dengue and lymphatic filariasis vectors along an altitudinal transect in Central Nepal.

ABSTRACT:

Background

Rapidly increasing temperatures in the mountain region of Nepal and recent reports of dengue fever and lymphatic filariasis cases from mountainous areas of central Nepal prompted us to study the spatio-temporal distribution of the vectors of these two diseases along an altitudinal transect in central Nepal.

Methodology/principal findings

We conducted a longitudinal study in four distinct physiographical regions of central Nepal from September 2011 to February 2012. We used BG-Sentinel and CDC light traps to capture adult mosquitoes. We found the geographical distribution of the dengue virus vectors Aedes aegypti and Aedes albopictus along our study transect to extend up to 1,310 m altitude in the Middle Mountain region (Kathmandu). The distribution of the lymphatic filariasis vector Culex quinquefasciatus extended up to at least 2,100 m in the High Mountain region (Dhunche). Statistical analysis showed a significant effect of the physiographical region and month of collection on the abundance of A. aegypti and C. quinquefasciatus only. BG-Sentinel traps captured significantly higher numbers of A. aegypti than CDC light traps. The meteorological factors temperature, rainfall and relative humidity had significant effects on the mean number of A. aegypti per BG-Sentinel trap. Temperature and relative humidity were significant predictors of the number of C. quinquefasciatus per CDC light trap. Dengue fever and lymphatic filariasis cases had previously been reported from all vector positive areas except Dhunche which was free of known lymphatic filariasis cases.

Conclusions/significance

We conclude that dengue virus vectors have already established stable populations up to the Middle Mountains of Nepal, supporting previous studies, and report for the first time the distribution of lymphatic filariasis vectors up to the High Mountain region of this country. The findings of our study should contribute to a better planning and scaling-up of mosquito-borne disease control programmes in the mountainous areas of Nepal.

SUBMITTER: Dhimal M

PROVIDER: S-EPMC4117448 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Publications

Spatio-temporal distribution of dengue and lymphatic filariasis vectors along an altitudinal transect in Central Nepal.

Dhimal Meghnath M Gautam Ishan I Kreß Aljoscha A Müller Ruth R Kuch Ulrich U

PLoS neglected tropical diseases 20140731 7

<h4>Background</h4>Rapidly increasing temperatures in the mountain region of Nepal and recent reports of dengue fever and lymphatic filariasis cases from mountainous areas of central Nepal prompted us to study the spatio-temporal distribution of the vectors of these two diseases along an altitudinal transect in central Nepal.<h4>Methodology/principal findings</h4>We conducted a longitudinal study in four distinct physiographical regions of central Nepal from September 2011 to February 2012. We u ...[more]

PMID: 25078276

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Project description:BackgroundHydrocele is a chronic condition in males in which there is an excessive collection of straw-colored fluid, which leads to enlargement of the scrotum. It is a common manifestation of lymphatic filariasis (LF) affecting nearly 25 million men worldwide. Surgery is the recommended treatment for hydrocele and is available free of cost in all government hospitals in Nepal. This research explored patient, provider, and community factors related to accessing hydrocele surgery services by the patients.MethodsThis study employed a qualitative method. The research was conducted in two LF endemic districts, namely Kanchanpur and Dhading, which are reported to have the highest number of hydrocele cases during morbidity mapping conducted in 2016. In addition to five key informant interviews with the LF focal persons (one national and 4 district-level), nine in-depth interviews were conducted with hydrocele patients (5 of whom had undergone surgery and 4 who had not undergone surgery) and with 3 family members, and two focus group discussions with the female community health volunteers.ResultsMost of the respondents did not have knowledge of hydrocele as one of the clinical manifestations of LF nor that it is transmitted through a mosquito bite. Although perceived as treatable with surgery, most of the patients interviewed believed in as well as practiced home remedies. Meanwhile, fear of surgery, embarrassment, lack of money, along with no knowledge of the free hydrocele surgery acted as barriers for accessing the surgery. On the other hand, financial support, flexible guidelines enabling the hospital to conduct surgery, decentralization and scaling up of morbidity mapping along with free hydrocele surgery camps in any remaining endemic districts were identified as enablers for accessing surgery.ConclusionHydrocele surgery coverage could be improved if the program further addresses community awareness. There is a need for more focus on information dissemination about hydrocele and hydrocele surgery.

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Dataset Information

Spatio-temporal distribution of dengue and lymphatic filariasis vectors along an altitudinal transect in Central Nepal.

Background

Methodology/principal findings

Conclusions/significance

Publications

Spatio-temporal distribution of dengue and lymphatic filariasis vectors along an altitudinal transect in Central Nepal.

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