Molecular surveillance of insecticide resistance in Phlebotomus argentipes targeted by indoor residual spraying for visceral leishmaniasis elimination in India

Molecular surveillance of resistance is an increasingly important part of vector borne disease control programmes that utilise insecticides. The visceral leishmaniasis (VL) elimination programme in India uses indoor residual spraying (IRS) with the pyrethroid, alpha-cypermethrin to control Phlebotomus argentipes the vector of Leishmania donovani, the causative agent of VL. Prior long-term use of DDT may have selected for knockdown resistance (kdr) mutants (1014F and S) at the shared DDT and pyrethroid target site, which are common in India and can also cause pyrethroid cross-resistance. We monitored the frequency of these marker mutations over five years from 2017–2021 in sentinel sites in eight districts of north-eastern India covered by IRS. Frequencies varied markedly among the districts, though finer scale variation, among villages within districts, was limited. A pronounced and highly significant increase in resistance-associated genotypes occurred between 2017 and 2018, but with relative stability thereafter, and some reversion toward more susceptible genotypes in 2021. Analyses linked IRS with mutant frequencies suggesting an advantage to more resistant genotypes, especially when pyrethroid was under-sprayed in IRS. However, this advantage did not translate into sustained allele frequency changes over the study period, potentially because of a relatively greater net advantage under field conditions for a wild-type/mutant genotype than projected from laboratory studies and/or high costs of the most resistant genotype. Further work is required to improve calibration of each 1014 genotype with resistance, preferably using operationally relevant measures. The lack of change in resistance mechanism over the span of the study period, coupled with available bioassay data suggesting susceptibility, suggests that resistance has yet to emerge despite intensive IRS. Nevertheless, the advantage of resistance-associated genotypes with IRS and under spraying, suggest that measures to continue monitoring and improvement of spray quality are vital, and consideration of future alternatives to pyrethroids for IRS would be advisable

Impact of IRS: Four-years of entomological surveillance of the Indian Visceral Leishmaniases elimination programme

BACKGROUND In 2005, Bangladesh, India and Nepal agreed to eliminate visceral leishmaniasis (VL) as a public health problem. The approach to this was through improved case detection and treatment, and controlling transmission by the sand fly vector Phlebotomus argentipes, with indoor residual spraying (IRS) of insecticide. Initially, India applied DDT with stirrup pumps for IRS, however, this did not reduce transmission. After 2015 onwards, the pyrethroid alpha-cypermethrin was applied with compression pumps, and entomological surveillance was initiated in 2016. METHODS Eight sentinel sites were established in the Indian states of Bihar, Jharkhand and West Bengal. IRS coverage was monitored by household survey, quality of insecticide application was measured by HPLC, presence and abundance of the VL vector was monitored by CDC light traps, insecticide resistance was measured with WHO diagnostic assays and case incidence was determined from the VL case register KAMIS. RESULTS Complete treatment of houses with IRS increased across all sites from 57% in 2016 to 70% of houses in 2019, rising to >80% if partial house IRS coverage is included (except West Bengal). The quality of insecticide application has improved compared to previous studies, average doses of insecticide on filters papers ranged from 1.52 times the target dose of 25mg/m2 alpha-cypermethrin in 2019 to 1.67 times in 2018. Resistance to DDT has continued to increase, but the vector was not resistant to carbamates, organophosphates or pyrethroids. The annual and seasonal abundance of P. argentipes declined between 2016 to 2019 with an overall infection rate of 0.03%. This was associated with a decline in VL incidence for the blocks represented by the sentinel sites from 1.16 per 10,000 population in 2016 to 0.51 per 10,000 in 2019. CONCLUSION Through effective case detection and management reducing the infection reservoirs for P. argentipes in the human population combined with IRS keeping P. argentipes abundance and infectivity low has reduced VL transmission. This combination of effective case management and vector control has now brought India within reach of the VL elimination targets

Evaluation of the role of HRCT chest in the differentiation of pattern of spectrum in lung diseases

Introduction: - CT is a modality used in imaging of internal structures/ organs by the use of radiation. HRCT is an examination protocol in CT for Lungs and Temporal bone. As HRCT uses thin slices so it provides detailed information which helps in better diagnosis. Aim and Objective:- To evaluate the Role of HRCT Chest in differentiation of pattern of spectrum in lung diseases to find out the different patterns in lung diseases. Methods & Materials:- The study was conducted on a period of 6 months on 30 patients. 16 slice CT machine was used for the scanning and thin sections were acquired by using HRCT protocols. Result:- In out of 30 patients, the common findings are Ground Glass Opacities, Tree In Bud Appearance, Reticular Opacities, Honey Combing, Consolidation Nodular Opacities. Conclusion:- HRCT chest is most important and valuable in diagnosis of lung diseases even when chest X-ray is normal. It is capable of imaging the lung with excellent spatial resolution and provides good anatomical detail

Knowledge, attitude, and practices among dental practitioners and postgraduate students on the preparedness of medical emergencies in Mathura City

Introduction: Medical emergencies can frequently happen in dental settings and the inability to cope with them can lead to tragic outcomes. Some factors can increase the risk of medical emergencies in dental settings. Aim: The aim of this study was to assess the knowledge, attitude, and practices among dental practitioners and postgraduate students on the preparedness of medical emergencies. Materials and Methods: A questionnaire-based study was conducted on 86 postgraduates students and 56 dental practitioners in Mathura city to evaluate their knowledge, attitude, and practices regarding the preparedness of medical emergencies. A self-administered, multiple-choice type of questionnaire was administered to each participant in person, who took approximately 12 min to complete the questionnaire. SPSS Version 22.0 (IBM Corp) was used for statistical analysis. Fisher's exact test was used and the value of P < 0.001 was considered to be statistically significant. Results: A total of 83 (96.5%) postgraduate students and 51 (94.4%) dental practitioners had knowledge regarding how to perform basic life support and first-aid, and only 28 (51.9%) dental practitioners could handle any emergency condition at their dental office. Furthermore, 45 (52.3%) postgraduate students and 49 (90.7%) dental practitioners attended workshops on emergency training (P < 0.001). Conclusion: Basic knowledge regarding diagnosis of medical emergencies and dealing with the same was better among the postgraduate students. They also had a better attitude toward handling of medical emergencies compared to dental practitioners. The dental practitioners ranked higher in majority of the aspects in handling medical emergencies

Effect of Rice Residue Retention and Foliar Application of K on Water Productivity and Profitability of Wheat in North West India

The rice&ndash;wheat cropping system being the backbone of food security in South-Asia has resulted in soil health deterioration, declining water table, and air pollution affecting livability index of the region. The effect of rice residue retention (RRR), irrigation levels and foliar application of K on wheat grain yield (GY), water use efficiency (WUE) and profitability was tested over three years. RRR increased wheat GY (5224 kg ha&minus;1), above-ground biomass (AGBM = 11.9 t ha&minus;1), tillers per square meter (TPM = 469) and grains per meter square (GrPMS = 13,917) significantly. Relative water content (RWC = 93.8) and WUE (2.45 k gm&minus;3) were also increased significantly by RRR. Consequently, profitability (Net return = 624.4 and Benefit to cost (B:C) ratio) was enhanced. Foliar application of K enhanced GY (5151 kg ha−1), AGBM (12 t ha−1), RWC (94.1), SPAD (52.2), WUE (2.40 kg m−3), net returns (625.2 ) and BC ratio (1.62) significantly. RRR increased GY (15.66%) and WUE (17.39%) with additional revenue of 151 $with only one irrigation at the CRI stage (ICS). RRR adopted over 10$ annually. RRR if adopted over existing practice on a large area would reduce environmental degradation with an enhanced income to small and marginal farmers