Добірка наукової літератури з теми "ANOPHELES CULICIFACIES"

A study was undertaken in the villages of Korea and Bastar district (Chhattisgarh) during the years 2012–2015 to investigate the bionomics of malaria vectors and the prevalence of their sibling species complexes. Entomological surveys carried out every month included indoor resting collections, pyrethrum spray catches, light trap catches, and insecticide susceptibility status of Anopheles culicifacies using World Health Organization (WHO) methods. Anopheles culicifacies and Anopheles fluviatilis species were assayed by polymerase chain reaction (PCR) for the detection of malaria parasite, and sibling species were identified using PCR and DNA sequencing. A total of 13,186 samples of Anopheles comprising 15 species from Bastar and 16 from Korea were collected. An. Culicifacies was recorded as the most dominant species and also the only active vector at both sites. This species was found to be resistant to dichlorodiphenyltrichloroethane (DDT) and Malathion, showing signs of emerging resistance against pyrethroids. Among the sibling species of An. culicifacies, the group BCE was found in maximum numbers, while sibling species T of the An. fluviatilis was recorded to be dominant among its complex. The study provides a comprehensive view of the vector bionomics in the highly malarious regions of India that may have importance in developing vector control strategies.

The Toxicological activity (larvicidal, adulticidal and repellent toxicity) of Vernonia anthelmintica seeds fraction was tested against different species of mosquito vectors viz, malaria (Anopheles culicifacies and Anopheles stephensi), filaria (Culex quinquefasciatus) and dengue (Aedes aegypti). The larvicidal toxicity of Vernonia anthelmintica seeds fraction was evaluated against the early 4th instars larvae of different mosquitoes species. Mean LC50 value of the column fraction KAL-4 from seeds of V. anthelmintica against the larvae of An. culicifacies, An. stephensi, Culex quinquifaciatus and Aedes aegpyti were found to be 64 ppm, 70 ppm, 143 ppm and 166 ppm respectively. The larvicidal toxicity was more against An. culicifacies, An. stephensi than Culex quinquifaciatus and Aedes aegypti. The seed extracts did not show any adulticidal toxicity and repellent toxicity even at 10% concentrated impregnated paper and 5% on human hand, respectively.

AbstractThree highly repetitive DNA sequences Rp36, Rp217 and Rp234, have been isolated from Anopheles culicifacies Giles sensu lato. The cloned DNA sequences were found at a higher copy number in species B and C, than in species A of the A. culicifacies complex. These sequences may therefore be used as DNA probes to distinguish species A from the other two species, using a 200-fold dilution of a single mosquito DNA extract in a dot-blot hybridization assay. Rp36 and Rp217 have been completely sequenced. Internal repeats were absent in Rp36. Two related core sequences of 13 and 16 bp were found tandemly repeated in Rp217. These probes enable the rapid detection of species A of A. culicifacies in field investigations.

Abstract Climate change is an important factor affecting the dynamics of the vectors population and, hence, the risk of vector-borne diseases. This study aimed to predict the environmental suitability for malaria vectors in Iran under climate change scenarios in 2030s and 2050s. Literature search was performed to find documents on the spatial distribution of Anopheles stephensi Liston, 1901, Anopheles culicifacies s.l. Giles, 1901, Anopheles fluviatilis s.l. James, 1902, Anopheles superpictus s.l. Grassi, 1899, Anopheles dthali Patton, 1905, Anopheles maculipennis s.l. Meigen, 1818, and Anopheles sacharovi Favre, 1903 (Diptera: Culicidae) published between 1970 and 2017. The bioclimatic data under three climate change scenarios (representative concentration pathway 2.6 [RCP2.6], RCP4.5, and RCP8.5) and MaxEnt model were used to predict the ecological niches for each species. Comparison between the two study periods under the three scenarios for each species revealed that RCP8.5 would reduce the area at risk for An. culicifacies s.l., An. dthali and An. superpictus s.l. in the 2050s compared to the 2030s, but the reverse will be induced by RCP2.6 and RCP4.5 scenarios. For An. fluviatilis s.l., RCP2.6 will reduce the risk areas in the 2050s, whereas an increase is expected under the two other scenarios. Moreover, all scenarios would decrease the high-risk areas of An. maculipennis s.l. in the 2050s. For An. sacharovi, RCP2.6 would increase its high-risk areas, whereas RCP4.5 and RCP8.5 would decrease its exposure. The high-risk area of An. stephensi is expected to increase under RCP8.5 in the 2030s and RCP4.5 in 2050s, but it will be almost unchanged or reduced under other scenarios.

Abstract Background Indoor residual spray (IRS) and long-lasting insecticidal nets are the two principal intervention methods of vector control. Zero vector durable lining (ZVDL), a relatively new vector control method, was evaluated to assess its efficacy against malaria vectors in hard to reach areas in the Balaghat district, where malaria transmission is perennial. Methods ZVDL was installed in six experimental villages during November–December 2012. In control villages, IRS was carried out with Alphacypermethrin. Cone bioassays were performed to assess the efficacy and persistence of insecticide-treated ZVDL following WHO bioassays. Results The mean per man hour density of Anopheles caught during 2013 was 12.1 in experimental villages and 16.2 in control villages. No sporozoite-positive Anopheles culicifacies were found in experimental villages; however, in control villages, four sporozoite-positive A. culicifacies were found (two Plasmodium vivax and two P. falciparum). The knock-down rate of A. culicifacies was 95–100% with 100% mortality during the 24 h recovery period. Malaria declined sharply in experimental villages showing a slide positivity rate of 22.3% compared with control villages (36.4%) (p<0.05). Conclusions A supplementary vector control intervention such as ZVDL has the potential to become a viable alternative to IRS in malaria endemic areas.

AbstractA significant effect of moon phase on light-trap catches of Anopheles species was observed during a longitudinal study carried out in a forested belt of Madhya Pradesh, India, inhabited by tribal people. However, moon phase does not seem to have any effect on the proportion of adult Anopheles culicifacies Giles in the total catch, or the parity rate in this species, which is the vector responsible for perennial transmission of malaria in the area.

Mosquitoes are the deadliest animals in the world and responsible for transmitting a variety of infectious disease such as malaria, dengue fever, chikungunya, zika fever. Among them, malaria which is transmitted by Anopheles mosquitoes is one of the major vector-borne diseases that cause millions of mortality and morbidity worldwide. Continuous climate change, global warming, and other environmental factors are the facilitators of mosquito population growth and thus worse the situation of mosquitoborne diseases. Current tools to control and manage malaria face challenges due to the emergence of parasite resistance to antimalarial drugs and insecticide resistance of mosquitoes. Thus, alternative approaches are needed for the global elimination of malaria. Evolution and adaptation of blood feeding behavior of adult female mosquitoes not only favored their reproductive success but also make them an important disease vectors. Mosquitoes rely extensively on their sense of smell (olfaction) for the majority of their lifecycle stages and the well-developed nasal system plays an essential role in the facilitation of olfactory guided behavior. Thus, decoding the genetic relationship of the neuro-olfactory system managing host seeking and blood feeding behavioral responses of adult female mosquitoes, may provide an opportunity to design new molecular strategy to disrupt human-mosquito interactions. Our RNA-Seq analysis of the neuro-olfactory system of Anopheles culicifacies mosquito, which transmit more than 65% malaria cases in rural India, unravelled that a tight coordination of the olfactory and the central nervous system is necessary to regulate the ‘pre and post’ blood meal associated with complex behavioral responses such as host-seeking, blood feeding, and oviposition. A comprehensive molecular cataloging and comparative gene expression analysis of the olfactory tissue transcriptome data indicated that synergetic actions of the olfactory encoded molecular factors (Odorants Binding Proteins and Olfactory receptors) facilitate and manage the complex host-seeking behavioral events. Next, transcriptional profiling of the selected olfactory transcripts in two consecutive blood feeding experiment highlighted that adult female mosquitoes might learn and memorize from the priming effect of the first blood meal exposure, which further facilitates host selection and rapid blood meal uptake during second blood feeding event. Furthermore, species-specific transcriptional profiling and an in-silico analysis of novel ‘sensory appendages proteins’ revealed their potential role in host-seeking and blood feeding behavior, possibly a unique target for functional characterization and designing of molecular strategy for the control of An. culicifacies mosquitoes. Our comparative vi RNA-Seq analysis of naïve and blood fed adult female mosquitoes brain unraveled that a gradual modulation of brain transcripts expression is crucial to regulate the complex events linked to metabolic switch activities such as blood meal digestion, egg maturation, oviposition etc. Finally, the characterization of two olfactory-specific proteins Quick-to-Court and Attractin provide a new knowledge that how mosquitoes manage the conflicting demand of mating vs. blood feeding.