Publications by authors named "Ishan Gautam"

In 2023, Nepal faced its second largest dengue outbreak ever, following a record-breaking number of dengue cases in 2022, characterized by the expansion of infections into areas of higher altitudes. However, the characteristics of the 2023 circulating dengue virus (DENV) and the vector density remain poorly understood. Therefore, we performed DENV serotyping, clinical and laboratory assessment, and entomological analysis of the 2023 outbreak in central Nepal.

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Background: Larval source management is an effective measure to control mosquito-borne diseases. Bacillus thuringiensis produces specific insecticidal crystal proteins toxic to mosquito larvae. In many parts of the South East Asian region, Bacillus thuringiensis is used for larval source management.

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Article Synopsis
  • Invasive vector species, like Aedes aegypti, are spreading to colder areas due to globalization, urbanization, and climate change, posing health risks to humans.
  • Researchers studied these mosquitoes in Nepal to understand how their genomes adapt to different environments, particularly at various altitudes.
  • They found distinct genetic differences between highland and lowland populations, highlighting mutations that may enhance survival in colder climates, suggesting a potential for these vectors to expand into new regions.
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Background: Vector-borne diseases are on the rise on a global scale, which is anticipated to further accelerate because of anthropogenic climate change. Resource-limited regions are especially hard hit by this increment with the currently implemented surveillance programs being inadequate for the observed expansion of potential vector species. Cost-effective methods that can be easily implemented in resource-limited settings, e.

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Article Synopsis
  • Mites Anderson and Trueman and Anderson and Morgan pose significant risks to beekeeping due to their impact on bee populations.
  • Hygienic behavior in bees, which involves removing diseased or damaged brood, shows a strong correlation in response to both types of mites, suggesting a potential for targeted breeding strategies.
  • The comparison of hygienic behavior between different bee species indicates that the Asiatic honey bee is more effective in eliminating infested cells, contributing to its resistance against these mites.
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Background: The expansion of dengue vectors from lowland plains to the upland hilly regions of Nepal suggests the likelihood of increased risk of dengue. Our objective was to assess the effects of meteorological variables on vector indices and populations of dengue vectors in two different ecological regions of Nepal. An entomological survey was conducted in Kathmandu and Lalitpur (upland) and Chitwan (lowland) of Nepal in three different seasons from July 2015 to May 2016.

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Article Synopsis
  • - Dengue fever is a significant public health issue in Nepal, primarily transmitted by the Aedes aegypti mosquito, and this study aimed to assess dengue seropositivity and the bacterial diversity in these mosquitoes from affected regions.
  • - Conducted between June and November 2013, the study analyzed 221 serum samples for anti-dengue IgM and collected mosquito larvae to identify the bacterial communities present in A. aegypti.
  • - Results showed a 15.38% seropositivity rate for dengue and highlighted that gram-negative bacteria were the most commonly isolated, with Staphylococcus spp., Pseudomonas spp., and Acinetobacter spp. being the predominant strains found in the mosquito's gut.
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A descriptive cross-sectional study was carried out among 264 suspected dengue patients in two districts (Dang and Chitwan) of Nepal from June 2013 to November 2013. The anti-dengue IgM positivity was found to be (51/264)19.31% by capture ELISA, of which 21 (41.

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Background: Dengue fever (DF) is an emerging public health problem in Nepal, and yet neither the magnitude of the DF burden or its epidemiological trends are well understood.

Methods: We conducted a sero-epidemiological, seasonal trend and demographic analysis of the trends in DF in the Terai region of Nepal, from 2007 to 2013. In that period, 2002 serum samples were collected from febrile patients suspected of dengue virus infection.

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Background: The presence of the recently introduced primary dengue virus vector mosquito Aedes aegypti in Nepal, in association with the likely indigenous secondary vector Aedes albopictus, raises public health concerns. Chikungunya fever cases have also been reported in Nepal, and the virus causing this disease is also transmitted by these mosquito species. Here we report the results of a study on the risk factors for the presence of chikungunya and dengue virus vectors, their elevational ceiling of distribution, and climatic determinants of their abundance in central Nepal.

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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.

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Background: Dengue fever (DF) is the most rapidly spreading mosquito-borne viral disease in the world. In this decade it has expanded to new countries and from urban to rural areas. Nepal was regarded DF free until 2004.

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Dengue is an emerging disease in Nepal and was first observed as an outbreak in nine lowland districts in 2006. In 2010, however, a large epidemic of dengue occurred with 4,529 suspected and 917 serologically-confirmed cases and five deaths reported in government hospitals in Nepal. The collection of demographic information was performed along with an entomological survey and clinical evaluation of the patients.

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