Cotton leaf curl disease (CLCuD) outbreaks caused by CLCuD associated begomoviruses (CABs) significantly constrain cotton production in India and Pakistan. In comparison to the CABs circulating in Pakistan, molecular epidemiology, evolution and recombination patterns of CABs circulating in India are less studied. In this work, we characterized CAB complex sequences obtained from the most recent outbreak (Punjab, India, 2015), and rigorously analyzed them with reference to GenBank sequences, submitted from India, Pakistan and other neighbouring countries, using contemporary bioinformatics approaches. In this manuscript, we illustrate the detection of a recombinant, phylogenetically distinct clade of Cotton leaf curl Multan virus (CLCuMuV), suggesting rebound of CLCuMuV in this region. Interestingly, we could not detect Cotton leaf curl Kokhran virus-Burewala strain (CLCuKoV-Bu), which was prevalent in this region, until now. Our study thus indicates substitution of the ‘virulent resistance breaking’ CLCuKoV-Bu by the re-emerging CLCuMuV recombinants. Our findings corroborate with that of a very recent study from Pakistan and we here discuss epidemiological links between the CAB complexes reported in these two studies. Taken together, these observations signify a shifting epidemiology of CABs, and seem to correlate with the recent prediction of the ‘third epidemic’ of CLCuD in the Indian subcontinent.

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a b s t r a c tBackground: Vector monitoring in military stations would help in protecting the armed forces from vector borne diseases such as malaria, Japanese encephalitis and filariasis.Methods: Adult mosquitoes were collected from four villages around a military station in India using light traps and the species composition was estimated. Insecticide susceptibility of disease vectors against DDT, deltamethrin and permethrin was established using WHO kits.Results: The known malaria vectors constituted 4.9% of the total mosquito collections and Anopheles philippinensis/nivipes (2.05%) was the most abundant. Japanese encephalitis and dengue vectors constituted 25.3 and 0.05% whereas the known vectors of both Japanese encephalitis and filariasis formed 50.9%. The mean (AESE mean ) of annual parasitic index, slide positivity and Plasmodium falciparum percentage among the civilian population during the study period were 1.46 AE 0.37, 1.65 AE 0.77 and 50.2 AE 10.7. The filariasis vector Culex quinquefasciatus was resistant to DDT with 65.4% mortality whereas the DDT resistance in the Japanese encephalitis vector Culex vishnui gr. with 91.9% mortality needs to be confirmed. All other species tested were susceptible to DDT, deltamethrin and permethrin.

Insecticidal fabrics are effective personal protective measures against disease vectors and unlike bed nets, these fabrics can provide protection from day-biting mosquitoes and in outdoor environments. The rapid geographical expansion of day-biting mosquitoes and their role in disease transmission necessitate technological interventions, which can be effectively used during the daytime. There is a renewed interest in insecticidal fabrics mainly due to the recent outbreaks and geographical spread of dengue and chikungunya and with the emerging threat of Zika virus infection. Insecticidal fabrics are useful for protection from night-biting mosquitoes and also in situations were sleeping under a bed net is not possible. They are also effective against other biting arthropods like ticks, mites, tsetse flies, sand flies and body lice. Although long-lasting insecticidal fabrics factory-treated with permethrin are now commercially available for military and civilian use, there are no international guidelines for testing their efficacy. The different methods employed so far for testing bioefficacy, washing and quantification of permethrin are compiled in this review. The future prospects and challenges ahead for long-lasting insecticidal fabrics are discussed in the context of the increased threat from day-biting mosquitoes and the diseases transmitted by them. The review focuses on the need for standardisation of the test methods for ensuring adequate bioefficacy and safety to the user. The differences between long-lasting insecticidal nets and long-lasting insecticidal fabrics are elaborated, and the need for a separate registration and licencing procedure for long-lasting insecticidal fabrics is highlighted. A test procedure for insecticidal fabrics is described, which could be used until internationally accepted guidelines are available.

The prevalence and bionomics of known Indian malaria vector anophelines was studied in three forest fringe villages in Sonitpur district of Assam, India. Anopheles philippinensis/nivipes (36.8%) and An. annularis (25.6%) were the most abundant of the seven vector anopheline species recorded. Densities of vector anophelines in general were high during monsoon season and low during winter months. An. dirus s.l. was the most anthropophagic (91.6%) of all the species collected whereas, An. annularis, An. fluviatilis s.l. and An. varuna were predominantly zoophagic. The highest and the lowest slide positivity rates (SPR) was recorded during monsoon (36%) and winter (12.5%) seasons, respectively. SPR was positively correlated with vector anopheline densities (r = 0.902), which itself was found to be correlated with mean minimum temperature and relative humidity (RH).

With the evolution of material science, researchers are deeply concerned about the utility of sustainable resources for multifaceted advanced applications.Here we project an abundant, nonedible bioresource-based carbon dot−silver nanohybrid as a highly competent larvicidal agent against Culex quinquefasciatus. Mosquitoes have been the closest enemy of humankind for a very long time. Tropical areas around the globe suffer severe ailments due to mosquitovector-borne diseases. Japanese encephalitis, lymphatic filariasis, etc. are such fatal threats spread by Culex species. With the emergence of nanotechnology, the perspectives of conventional antivector materials have changed dramatically. The C-dot precursor used here was the roots of Cyperus rotundus, a very abundant grass species found in South Asian countries. The nanohybrid was synthesized by a simple thermal approach without the application of additional reducing agent. The nanohybrid was distributed within a narrow size window of <10 nm. The material was extremely effective against C. quinquefasciatus larvae at a concentration of only 0.05 ppm. Electron microscopic evidence put forward the fact that the material enters the larval body by rupturing the cuticular membrane, subsequently destroying the intestinal system. Thus, the investigation endorses a sustainable nanoweapon to combat the aforesaid vector with immense potential for field applications.

Objective: We report the phylogenetic characterization of a unique flavivirus sequence detected in a wild Culex tritaeniorhynchus mosquito pool, collected from the northeast Indian state of Assam. Methods: DNA and RNA were extracted from field-collected mosquito pools. Extracts were subjected to PCR and reverse transcriptase PCR amplification using universal and type-specific primers for direct detection of flavivirus-specific viral nucleic acids. An amplified flavivirus nonstructural protein 5 (NS5) genetic region was sequenced and BLAST searched, and phylogenetic analyses performed with reference sequences retrieved from GenBank. Results: Phylogenetic analyses revealed the sequence to be related to insect-specific flaviviruses (ISFs) of the genus Flavivirus, family Flaviviridae. Despite being related to the Palm Creek virus (PCV; an ISF very recently reported from Northern Australia), the present sequence (provisionally named Assam virus) was found to be highly divergent from PCV and other ISF sequences available in GenBank. The partial NS5 sequence analysis demonstrated low nucleotide sequence identity (66-77%) with known ISFs reported from other parts of the globe. Conclusion: Findings of this study suggest the presence of a candidate novel ISF - the first to be reported from India.

The loss of permethrin from impregnated uniforms due to repeated washings was studied by chromatographic estimation of the residues. The mean (± SE mean ) percentage losses of permethrin after one to five washings were 16.7 ± 2.3, 22.5 ± 3, 29.6 ± 2.9, 40.2 ± 2 and 52.2 ± 2.4, respectively. The reduction in contact toxicity against mosquitoes after each washing was studied by World Health Organization tube and cone bioassays against Aedes albopictus mosquitoes. The median knockdown time for 5-min exposure to the treated uniforms increased from 5.9 to 71.8 min after five washings. Mosquito mortality 24 h post-exposure in cone bioassays was \80 % after the fifth washing, indicating the loss of efficacy. The uniforms need to be retreated after five washings so as to ensure adequate protection against disease vectors. The washing water should be properly disposed off to prevent environmental contamination and toxicity to aquatic organisms. Methods for treatment of military uniforms, which ensure high resistance to washing, need to be adopted so as to avoid frequent re-impregnations with permethrin.