Nature's Solution to Aedes Vectors: Toxorhynchites as a Biocontrol Agent.

This review summarizes the predatory potential of Toxorhynchites mosquitoes as biological control agents for Aedes vectors. A single larva can consume hundreds of mosquito larvae during its development, with preference for larger prey and higher consumption rates at higher prey densities. Studies suggest Toxorhynchites can significantly reduce Aedes populations. Beyond direct predation, they may indirectly influence prey behavior and adult mosquito lifespan. Despite the demonstrably positive effects of Toxorhynchites species as biocontrol agents, there are acknowledged limitations that require further investigation. These limitations include potential variations in effectiveness across diverse habitats and mosquito developmental stages. Additionally, long-term ecological sustainability and potential ramifications warrant further research. Future efforts should prioritize optimizing rearing and release strategies to enhance effectiveness. Exploring the potential for combined control methods with other biocontrol agents or traditional methods is also crucial. Finally, investigating the influence of environmental factors on predation rates can further refine and optimize the application of Toxorhynchites in mosquito control programs.

Investigating public understanding and actions regarding Aedes mosquitoes and dengue prevention across altitudinal range in central Nepal.

BACKGROUNDS OBJECTIVES: Dengue fever, transmitted by Aedes mosquitoes, is a significant public health concern in Nepal. An extensive Knowledge, Attitude, and Practice (KAP) survey related to Aedes mosquitoes and the prevention of dengue was conducted along the route from Matihani (62 m asl) to Kalinchok (3840 m asl) in central Nepal. This research examined residents' awareness of Aedes mosquitoes and the diseases they transmit, aiming to support the World Health Organization's national and global fight against mosquito-borne diseases. METHODS: The survey included 550 participants aged 18-75 years (249 males and 201 females). Door-to-door campaigns were conducted to gather data on knowledge scores, practices, and attitudes about Aedes mosquitoes using a standard structured questionnaire. RESULTS: Findings of this study revealed a moderate level of knowledge across the study area, with a mean knowledge score of 5.525±2.58 (correct answer rate of 46.05%). While 99.6% of respondents were aware of dengue transmission by mosquitoes, only 64.5% were able to report Aedes mosquitoes as the key transmitter. Less than one-third of the participants (27.8%) were familiar with black-and-white stripes in Aedes. Additionally, only 36.7% were knowledgeable about the day-biting behavior of Aedes mosquitoes. INTERPRETATION CONCLUSION: This KAP survey provides valuable insights into community understanding of Aedes mosquitoes and dengue prevention practices associated with various Nepalese communities residing in low to high altitudes of Central Nepal. The findings of this study can be adopted to address the increasing health burden faced by the countries with low- to-high altitude regions within the Hindu Kush Himalaya.

Characterization of Thermostable Cellulase from Bacillus licheniformis PANG L Isolated from the Himalayan Soil.

This study aimed to isolate, purify, and characterize a potential thermophilic cellulase-producing bacterium from the Himalayan soil. Eleven thermophilic bacteria were isolated, and the strain PANG L was found to be the most potent cellulolytic producer. Morphological, physiological, biochemical, and molecular characterization identified PANG L as Bacillus licheniformis. This is the first study on the isolation of thermostable cellulase-producing Bacillus licheniformis from the Himalayan soil. This bacterium was processed for the production of cellulase enzyme. The optimum conditions for cellulase production were achieved at 45°C after 48 h of incubation at pH 6.5 in media-containing carboxymethyl cellulose (CMC) and yeast extract as carbon and nitrogen sources, respectively, in a thermo-shaker at 100 rpm. The enzyme was partially purified by 80% ammonium sulphate precipitation followed by dialysis, resulting in a 1.52-fold purification. The optimal activity of partially purified cellulase was observed at a temperature of 60°C and pH 5. The cellulase enzyme was stable within the pH ranges of 3-5 and retained 67% of activity even at 55°C. Cellulase activity was found to be enhanced in the presence of metal ions such as Cd2+, Pb2+, and Ba2+. The enzyme showed the highest activity when CMC was used as a substrate, followed by cellobiose. The Km and Vmax values of the enzyme were 1.8 mg/ml and 10.92 µg/ml/min, respectively. The cellulase enzyme obtained from Bacillus licheniformis PANG L had suitable catalytic properties for use in industrial applications.

Imidacloprid poisoning in a young female: a case report.

BACKGROUND: Imidacloprid, a neonicotinoid insecticide, is widely used in agricultural settings. Consequently, cases of accidental and suicidal poisoning are increasingly seen in clinical practice. Although cases with varied clinical presentations and toxicological profiles have been reported, standard management principles are lacking. CASE PRESENTATION: We present a case of Imidacloprid poisoning in a 25-year-old previously healthy indigenous Tamang female without a classic toxidrome requiring ventilatory support, complicated by a prolonged neuropsychiatric sequela. CONCLUSIONS: Although uncommonly reported, imidacloprid toxicity may lead to life-threatening complications and hence should be suspected in cases of unidentified poisoning with a relevant toxidrome. Vigilance on the part of treating physicians plays a crucial role in appropriate management.

Isolation of Lactococcus garvieae NEP21 from raw cow (Bos indicus) milk in Nepal.

Lactococcus garvieae is an emerging zoonotic pathogen impacting both humans and animals. Infection of this bacterium is known to cause mastitis in cattle, and endocarditis, osteomyelitis, liver abscess, and gastrointestinal problems are reported in immunocompromised and elderly people that regularly consume or handle raw meat, milk, dairy products, and seafood. This study aimed at investigating and detecting lactic acid bacteria in raw cow (Bos indicus) milk samples from a smallholder farm in Nepal. Based on the plate culture, biochemical tests, and molecular sequencing of 16 s ribosomal RNA coding nuclear DNA region followed by phenotypic and genotypic analyses, L. garvieae NEP21 was detected and identified for the first time in Nepal in raw cow milk samples. This finding suggests the prevalence of L. garvieae NEP21 in raw cow milk and recommends further research and surveillance for understanding the extent of its presence in Nepal and globally for informed management of its infection in cattle and humans.

When muscle quivers and undulates.

We describe a patient who presented with fatigue and pulling sensation in his lower limbs. He had continuous muscle contractions over his trunk (myokymia) which pointed towards the diagnosis of Isaacs syndrome which was confirmed by strongly positive CASPR2 antibodies in blood.

Production Optimization and Biochemical Characterization of Cellulase from Geobacillus sp. KP43 Isolated from Hot Spring Water of Nepal.

This study is aimed at isolating and identifying a thermophilic cellulolytic bacterium from hot spring water and characterizing thermostable cellulase produced by the isolate. Enrichment and culture of water sample was used for isolation of bacterial strains and an isolate with highest cellulase activity was chosen for the production, partial purification, and biochemical characterization of the enzyme. Different staining techniques, enzymatic tests, and 16s ribosomal DNA (16s rDNA) gene sequencing were used for the identification of the isolate. The cellulase producing isolate was Gram positive, motile, and sporulated rod-shaped bacterium growing optimally between 55°C and 65°C. Based on partial 16s rDNA sequence analysis, the isolate was identified as Geobacillus sp. and was designated as Geobacillus sp. KP43. The cellulase enzyme production condition was optimized, and the product was partially purified and biochemically characterized. Optimum cellulase production was observed in 1% carboxymethyl cellulose (CMC) at 55°C. The molecular weight of the enzyme was found to be approximately 66 kDa on 12% SDS-PAGE analysis. Biochemical characterization of partially purified enzyme revealed the temperature optimum of 70°C and activity over a wide pH range. Further, cellulase activity was markedly stimulated by metal ion Fe2+. Apart from cellulases, the isolate also depicted good xylanase, cellobiase, and amylase activities. Thermophilic growth with a variety of extracellular enzyme activities at elevated temperature as well as in a wide pH range showed that the isolated bacteria, Geobacillus sp. KP43, can withstand the harsh environmental condition, which makes this organism suitable for enzyme production for various biotechnological and industrial applications.

RATIONAL FOR CONTINUING TERLIPRESSIN AFTER ENDOSCOPIC VARICEAL LIGATION IN ACUTE VARICEAL HAEMORRHAGE NEEDS FURTHER EVIDENCE: A PILOT STUDY.

BACKGROUND: Variceal hemorrhage (VH) is a medical emergency. Prompt endoscopic variceal ligation (EVL) is therapeutic. Terlipressin is used in VH and continued for 2-5 days even after EVL. As hemostasis is primarily achieved by EVL, the benefit of continuing trelipressin after EVL is unknown. OBJECTIVE: To evaluate the efficacy of continuing terlipressin after EVL to prevent re-bleed and mortality. METHODS: In this pilot study, after EVL 74 patients of VH were randomized into two treatment groups TG2 & TG5, received terlipressin (1 mg IV bolus q 4 hourly) for 2 days and 5 days respectively and one control group (TG0), received 0.9% normal saline (10 mL IV bolus q 4 hourly) and followed up for 8 weeks. RESULTS: A total of 9 (12.6%) patients had re-bleed with maximum 4 (5.6%) patients in TG5 group followed by 3 (4.2%) in TG2 and 2 (2.8%) in TG0 groups (P=0.670). The overall mortality was 15 (21.1%) patients, 6 (8.5%) patients in TG0 group, followed by 5 (7.0%) in TG5 and 4 (5.6%) in TG2 group (P=0.691). Adverse drug reactions were significantly higher in treatment groups with maximum 18 (24.32%) patients in TG5, followed by 8 (10.8%) in TG2 and 2 (2.7%) in TG0 groups (P=0.00). Duration of hospital stay was also significantly higher in treatment group, 6.63 (±0.65) days in TG5 followed by 3.64 (±0.57) in TG2 and 2.40 (±0.50) days in TG0 groups (P=0.00). CONCLUSION: The rational for continuing terlipressin after EVL is doubtful as it didn't have any benefit for the prevention of re-bleed or mortality; rather it increased the risk of adverse drug reactions and duration of hospital stay. Further randomized clinical trials are encouraged to generate more evidence in support or against continuing terlipressin after EVL.

O uso contínuo da terlipressina após a ligadura endoscópica em hemorragia varicosa aguda necessita de mais evidências: um estudo piloto / Rational for continuing terlipressin after endoscopic variceal ligation in acute variceal haemorrhage needs further evidence: a pilot study

ABSTRACT Background Variceal hemorrhage (VH) is a medical emergency. Prompt endoscopic variceal ligation (EVL) is therapeutic. Terlipressin is used in VH and continued for 2—5 days even after EVL. As hemostasis is primarily achieved by EVL, the benefit of continuing trelipressin after EVL is unknown. Objective To evaluate the efficacy of continuing terlipressin after EVL to prevent re-bleed and mortality. Methods In this pilot study, after EVL 74 patients of VH were randomized into two treatment groups TG2 & TG5, received terlipressin (1 mg IV bolus q 4 hourly) for 2 days and 5 days respectively and one control group (TG0), received 0.9% normal saline (10 mL IV bolus q 4 hourly) and followed up for 8 weeks. Results A total of 9 (12.6%) patients had re-bleed with maximum 4 (5.6%) patients in TG5 group followed by 3 (4.2%) in TG2 and 2 (2.8%) in TG0 groups (P=0.670). The overall mortality was 15 (21.1%) patients, 6 (8.5%) patients in TG0 group, followed by 5 (7.0%) in TG5 and 4 (5.6%) in TG2 group (P=0.691). Adverse drug reactions were significantly higher in treatment groups with maximum 18 (24.32%) patients in TG5, followed by 8 (10.8%) in TG2 and 2 (2.7%) in TG0 groups (P=0.00). Duration of hospital stay was also significantly higher in treatment group, 6.63 (±0.65) days in TG5 followed by 3.64 (±0.57) in TG2 and 2.40 (±0.50) days in TG0 groups (P=0.00). Conclusion The rational for continuing terlipressin after EVL is doubtful as it didn't have any benefit for the prevention of re-bleed or mortality; rather it increased the risk of adverse drug reactions and duration of hospital stay. Further randomized clinical trials are encouraged to generate more evidence in support or against continuing terlipressin after EVL.

RESUMO Contexto A hemorragia varicosa (HV) é emergência médica. A ligadura endoscópica imediata das varizes (LEV) é terapêutica. A terlipressina é usada em HV e contínua por 2—5 dias mesmo após a LEV. Como a hemostasia é alcançada principalmente pela LEV, o benefício do uso contínuo da terlipressina após o evento é desconhecido. Objetivo Avaliar a eficácia da terlipressina contínua após a LEV para evitar o ressangramento e a mortalidade. Métodos Neste estudo piloto, após a LEV, 74 pacientes com HV foram randomizados em dois grupos de tratamento TG2 & TG5, que receberam terlipressina (1 mg EV em bolus a cada 4 horas) durante 2—5 dias, respectivamente, e um grupo controle (TG0), que receberam soro fisiológico normal de 0,9% (10 mL EV em bolus a cada 4 horas) e foram seguidos por 8 semanas. Resultados Um total de 9 (12,6%) pacientes tiveram ressangramento, 4 (5,6%) no grupo TG5, seguidos por 3 (4,2%) no TG2 e 2 (2,8%) no grupo TG0 (P=0,670). A mortalidade geral de pacientes foi de 15 (21,1%), 6 (8,5%) no grupo TG0, seguidos por 5 (7,0%) no TG5 e 4 (5,6%) no TG2 (P=0,691). As reações adversas de medicamentos foram significativamente maiores em grupos de tratamento em 18 (24,32%) pacientes no TG5, seguidos por 8 (10,8%) no TG2 e 2 (2,7%) em grupo TG0 (P=0,00). A duração da internação hospitalar também foi significativamente maior no grupo de tratamento, 6,63 (±0,65) dias no TG5, seguido por 3,64 (±0,57) em TG2 e 2,40 (±0,50) dias em grupos TG0 (P=0,00). Conclusão O uso racional para a continuação da terlipressina após a LEV é duvidoso, pois não teve qualquer benefício para a prevenção de ressangramento ou mortalidade; pelo contrário, aumentou o risco de efeitos adversos e duração da internação hospitalar. Outros ensaios clínicos randomizados são necessários para gerar mais evidências em apoio ou contra a terlipressina contínua após a LEV.

First report on the molecular detection of Entamoeba bovis from the endangered wild water buffalo (Bubalus arnee) in Nepal.

BACKGROUND: The Asiatic wild water buffalo (Bubalus arnee) is an endangered species that is conserved in the Koshi Tappu Wildlife Reserve (KTWR), Nepal, and was recently translocated to the Chitwan National Park (CNP). Gastrointestinal (GI) parasites are the cause of significant negative health and production impacts on animals worldwide. METHODS: A coprological survey of GI parasites of wild water buffalo was carried out in the CNP in 2020. Fresh dung samples (n = 25) were collected from wild water buffaloes and analysed using sedimentation and flotation techniques for morphological identification of parasite cysts, oocysts and eggs. RESULTS: Nine different GI parasites were recorded of which Entamoeba spp. (20 samples, 80%) were the most common. The presence of Entamoeba spp. was further validated using polymerase chain reaction (PCR) analysis and DNA sequencing. The PCR results were positive for all of the microscopically positive samples, and the species was identified as Entamoeba bovis. Three samples were sequenced and formed a cluster of E. bovis, which was separated from other Entamoeba spp. in phylogenetic analysis. CONCLUSION: This is the first report for molecular detection of E. bovis from wild water buffaloes in Nepal. Future work should focus on the prevalence of such infections in water buffaloes in forest environments.

Factors affecting utilization of sexual and reproductive health services among women with disabilities- a mixed-method cross-sectional study from Ilam district, Nepal.

BACKGROUND: Persons with disabilities can have physical, mental, intellectual, or sensory impairments which can hinder their social participation. Despite Sustainable Development Goals call for "universal access to sexual and reproductive health (SRH)", women with disabilities (WwDs) continue to experience barriers to access SRH services in Nepal. This study evaluated factors affecting the utilization of SRH services among WwDs in Ilam district, Nepal. METHODS: A mixed-method study with 384 WwDs of reproductive age was conducted in Ilam district, eastern Nepal. Quantitative data were collected using a structured questionnaire. Relationships between utilization of SRH services and associated factors were explored using multivariate logistic regression analysis. Qualitative data were collected from focus groups with female community health volunteers and interviews with WwDs, health workers and local political leaders. They were audio-recorded, translated and transcribed into English and were thematically analyzed. RESULTS: Among 384 respondents (31% physical; 7% vision,16% hearing, 7% voice&speech,12% mental/psychosocial, 9% intellectual, 18% multiple disabilities), only 15% of them had ever utilized any SRH services. No requirement (57%) and unaware of SRH services (24%) were the major reasons for not utilizing SRH services. A majority (81%) of them reported that the nearest health facility was not disability-inclusive (73%), specifically referring to the inaccessible road (48%). Multivariate analysis showed that being married (AOR = 121.7, 95% CI: 12.206-1214.338), having perceived need for SRH services (AOR = 5.5; 95% CI: 1.419-21.357) and perceived susceptibility to SRH related disease/condition (AOR = 6.0; 95% CI:1.978-18.370) were positively associated with the utilization of SRH services. Qualitative findings revealed that illiteracy, poor socioeconomic status, and lack of information hindered the utilization of SRH services. WwDs faced socioeconomic (lack of empowerment, lack of family support), structural (distant health facility, inaccessible-infrastructure), and attitudinal (stigmatization, bad behaviour of health care providers, perception that SRH is needed only for married) barriers to access SRH services. CONCLUSIONS: Utilization of SRH services among WwDs was very low in Ilam district, Nepal. The findings of this study warrant a need to promote awareness-raising programs to WwDs and their family members, sensitization programs to health service providers, and ensure the provision of disability-inclusive SRH services in all health facilities.

Molecular study of 2019 dengue fever outbreaks in Nepal.

BACKGROUND: Dengue cases have been continuously reported in Nepal, including some large outbreaks, since its first introduction in 2004. The disease is now expanding towards newer locations above 1400 m high, especially the country's capital city, Kathmandu. In 2019, >14,000 dengue cases including six deaths were reported. This study was aimed at the detection and molecular characterization of dengue virus (DENV) in dengue patients. METHODS: A total of 451 patients were enrolled in this study. Demographic, clinical and laboratory information was collected from dengue patients. Dengue infection was confirmed by antibody/antigen detection assays followed by RT-PCR analysis. RESULTS: The DENV patients showed fever, body ache, headache, myalgia, retro-orbital pain and arthralgia. The platelets were decreased, serum liver enzymes were increased and leucopenia was seen. Out of 195 patients, 111 (57.0%) were positive for DENV RNA by consensus PCR. We found DENV-2, 70 (63.1%) as the predominant serotype responsible for the 2019 outbreak, while DENV-3 was detected in two patients. CONCLUSION: Our findings suggest that DENV-2 was the major serotype causing the 2019 massive outbreak in Nepal. This information will help in disease control programs to understand the molecular epidemiology and its changing trend.

First report of malaria parasites in water buffalo in Nepal.

We present the first molecular-based report on ungulate malaria parasites from water buffalo in Nepal. Fifty-six blood samples were collected from different groups of water buffalo (wild, feral, and domestic) and PCR assays were conducted using Plasmodium spp. cytb specific primers. Two positive cases were detected, one each from feral and domestic individuals. Complete mitochondrial genome sequence (5987 bp) was obtained and examined for nucleotide variations. Sequence analysis revealed identity with type II water buffalo malaria parasites, reported previously, with one A to T nucleotide difference at position 5344. Prevalence, as well as possible economic impacts of water buffalo malaria, should be determined on a wider set of samples from buffalo across Nepal.

Molecular evidence supports the expansion of visceral leishmaniasis towards non-program districts of Nepal.

BACKGROUND: Visceral Leishmaniasis (VL) is caused by a protozoan parasite Leishmania donovani that is transmitted to humans by an infected female sandfly, Phlebotomus argentipes. VL is common in the Indian sub-continent including Nepal and efforts for its elimination are ongoing. However, expansion of disease towards the higher altitude areas, previously considered as VL free in Nepal, may impact the ability to achieve the elimination target by 2020. METHODS: This was an exploratory study, where VL suspected patients living exclusively in the non-program districts of Nepal and presenting with fever > 2 weeks and splenomegaly was included. The patients' blood samples were collected, and DNA was extracted. DNA was subjected to PCR amplification and subsequent sequencing. Additionally, past 10 years data of VL cases from the national databases were analysed to see the trends of the disease in program and non program districts. RESULTS: Analysis of the past 10 years data revealed that trend of VL cases significantly decreased in the program districts (p = 0.001) while it increased in the non-program districts (p = 0.002). The national trend for overall incidence of VL also significantly decreased over this time period. Limited number of patients' samples (n = 14) were subjected to molecular investigation, and four patients were found to be positive for Leishmania species by PCR. Interestingly, these cases in non-program districts were indeed also L. donovoni complex. All four patients were male with age ranges from 10 to 68 years. GenBank BLAST of the obtained DNA sequences confirmed identified specimens as L. donovani complex. We identified additional VL cases from non-program districts (including the high lands) of Nepal, indicating that the infection could be an emerging threat for the non-program areas of Nepal. CONCLUSION: The demonstration of VL cases in areas initially considered non-endemic has raised concern about on-going transmission in those regions and may trigger subsequent government plan and action to include those areas in the elimination program. Thus, the government should consider revising the disease control programs to accommodate non-program districts for achieving the VL elimination goal set for 2020.

Geological and ecological factors drive cryptic speciation of yews in a biodiversity hotspot.

The interplay of orographic uplift and climatic changes in the Himalaya-Hengduan Mountains region (HHM) have had a key role in speciation and population demography. To gain further insight into these processes, we investigated their effects on Taxus wallichiana by combining molecular phylogeography and species distribution modeling. Molecular data were obtained from 43 populations of T. wallichiana. Nineteen climatic variables were analyzed alongside genetic discontinuities. Species distribution modeling was carried out to predict potential past distribution ranges. Two distinct lineages were identified, which diverged c. 4.2 (2.0-6.5) million years ago (Ma), a timescale that corresponds well with the recent uplift of the Qinghai-Tibet Plateau and subsequent climatic changes of the region. Correlations with climatic variables also suggest that ecological factors may have further reinforced the separation of the two lineages. Both lineages experienced population expansion during the last glaciation. The high genetic divergence, long-term isolation and ecological differentiation suggest a scenario of cryptic speciation in T. wallichiana associated with geological and climatic changes in the HHM. Our findings also challenge the notion of general population 'contraction' during the last glaciation in the HHM.