Background: Development of insecticide resistance occurred due to the continuous and misuse of synthetic insecticides therefore, the recent study was conducted to explore eco-friendly plant extracts that have some potential to suppress mosquito larval population.Methods: WHO recommended mosquito larval bioassay method for insecticide was used while for the analysis of citrus oils for limonin and nomilin content HPLC was used.Results: Among the two citrus cultivars tested as larvicide against Aedes albopictus, valencia late (Citrus sinensis) was the best in terms of LC50 (297 ppm), % mortality (97%) and LT50 (18.49 hours) then freutrall early (Citrus reticulate) with LC50 (377.4 ppm), % mortality (88%) and LT50 (31 hours), While nomilin gave lowest LC50 (121.04 ppm) than limonin (382.22 ppm) after 72 hours of exposure. Valencia late also had more limonin and nomilin (377 mg/ml and 21.19 mg/ml) than freutrall early (5.29 mg/ml and 3.89 mg/ml) respectively.Conclusion: Valencia late showed best results in term of LC50, LT50 and percentage mortality against Aedes albopictus as it has more amount of nomilin then freutrall early, however further evaluation in the field conditions is required.

Since the beginning, mosquito-borne diseases like dengue fever, encephalitis, yellow fever, malaria, and filariasis have been caused by numerous medically significant pathogens and parasites, including viruses, bacteria, and protozoans. This indicates the necessity for the ongoing creation of new and effective mosquito-borne disease control strategies in Saudi Arabia and internationally. This investigation has tried to assess the potential larvicidal capacity of local bacteria isolated from the soil of the Rahat region of Makkah, Saudi Arabia for the bio-control of Aedes aegypti larvae, a main cause of dengue. The bacteria were identified using morphological and molecular characteristics. Bioassays were used to determine the pathogenicity of various strains against A. aegypti larvae. A total of 66 different bacteria were isolated. Overall, four (6.06%) of the 66 bacteria caused mortality in the A. aegypti larvae, and only two (Brevibacillus centrosporus, and Cytobacillus firmus) caused 100% mortality in 24 h. After 48 h, two isolates (Escherichia fergusonii1 and E. fergusonii 2) caused mortality of over 70%. The outcomes of this investigation exhibited that local isolates of bacteria in the soils of the Rahat region of Makkah, Saudi Arabia, have larvicidal ability. These bacteria have shown larvicidal effects on the larvae of A. aegypti. In conclusion, further studies are required to evaluate other mechanisms that contribute to the production of larvicidal toxins in these bacteria.

Background: Dengue fever is a serious public health issue in Pakistan for many years. Globally plants have been reported to contain compounds with insecticidal properties. These properties have been demonstrated more recently on the larval stages of mosquitoes. Therefore, Citrus cultivar seeds were evaluated for larvicidal potential against the primary dengue vector Aedes aegypti. Methods: Extraction of oil was done by a steam distillation method and oils were evaluated according to WHO guidelines for larvicides 2005 for evaluation of insecticidal properties of citrus seed extracts against mosquito larvae. Result: Among the Citrus cultivar seed oil, rough lemon (Citrus jambhiri) had the lowest LC50 value (200. 79ppm), while musambi (C. sinensis var musambi) had the highest LC50 value (457. 30ppm) after 24 h of exposure. Conclusion: Citrus cultivars have some larvicidal potential but C. jambhiri had the greatest potential against A. ae-gypti larvae. Further small-scale field trials using the extracts of C. jambhiri will be conducted to determine opera-tional feasibility.

Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anopheles stephensi to a series of concentrations of the methanolic extracts. Methods: Susceptibility tests on Ae. aegypti and An. stephensi were conducted using standard WHO methods. The larvae of two mosquito species were exposed to methanolic extracts and mortality counts were made after 24 hours of exposure as per WHO method. Larvae of Ae. aegypti were more susceptible than that of An. stephensi.Results: Among the nine plant species tested, Annona reticulata leaf extract was more effective against Ae. Aegypti larvae with LC50 and LC90 values of 95.24 and 262.64 ppm respectively and against An. stephensi larvae 262.71 and 636.94 ppm respectively. The least efficacy was in Cosmos bipinnatus with LC50 and LC90 values of 442.6 and 1225.93 ppm against Ae. aegypti and LC50 and LC90 values of 840.69 and 1334.01 ppm of Thespesia populnea against An. stephensi.Conclusion: The crude methanolic extract of the An. reticulata with good larvicidal efficacy could be considered for further characterization to control mosquito vectors instead of chemical insecticides. High efficacy found in An. Reticulate extract will be considered for further studies to isolate the bioactive compound.

Background: Dengue fever in Indonesia is still high, and Bandung ranked the highest in the 33rd week of 2023. Dengue fever is a neglected tropical disease transmitted through the bite of Aedes aegypti. The school environment is at risk of DHF transmission because the biting time of Aedes aegypti coincides with student learning hours. The aim of this study was to determine the presence of Aedes aegypti larvae and their density in the elementary school environment.Methods: This study is a quantitative study with a cross-sectional design. The population of this study was all elementary schools in Bandung City, with 59 samples based on Slovin. The sample was determination using random number generation.Results: Environmental conditions of elementary schools are associated with the presence of larvae, with a P-value of 0.016. Observation results showed that 23 (39%) elementary schools found Aedes aegypti larvae. The House Index (HI) calculation was 39% and it was categorized at level 6 in the Fluke Index table. This indicates a high density of larvae. Breeding sites with larvae were in flower vases and water reservoirs in dispensers.Conclusion: Overall, our research findings indicate that the environment is a factor related to the discovery of Aedes aegypti larvae in elementary schools. With a high density of mosquito larvae, the school environment has the potential to spread dengue fever quickly.

Background: We aimed to extract the ingredients from leaves of Gossypium hirsutum (Bt cotton) using different solvents and evaluate for potential use to control different larval stages of mosquito species, Aedes aegypti and Anopheles stephensi.Methods: Qualitative and quantitative estimation of ingredients from Go. hirsutum (Bt) plant extract was carried out and their inhibitory action against mosquito larvae was determined using mosquito larvicidal assay.Results: LC50 values of water, ethanol, ethyl acetate and hexane extracts for Ae. aegypti were 211.73±21.49, 241.64±19.92, 358.07±32.43, 401.03±36.19 and 232.56±26.00, 298.54±21.78, 366.50±30.59, 387.19±31.82 for 4th instar of An. stephensi, respectively. The water extract displayed lowest LC50 value followed by ethanol, ethyl acetate and hexane. Owing to the comparatively better activity of water extract, its efficacy was further evaluated for mosquito larvicidal activity, which exhibited LC50 values of 133.95±12.79, 167.65±11.34 against 2nd and 3rd instars of Ae. aegypti and 145.48±11.76, 188.10±12.92 against 2nd and 3rd instars of An. stephensi, respectively. Crude protein from the water extract was precipitated using acetone and tested against 2nd, 3rd and 4th instars of Ae. aegypti and An. stephensi. It revealed further decrease in LC50 values as 105.72±25.84, 138.23±23.18, 126.19±25.65, 134.04±04 and 137.88±17.59, 154.25±16.98 for 2nd, 3rd and 4th instars of Ae. aegypti and An. stephensi, respectively.Conclusion: Leaves extracts of Go. hirsutum (Bt) is potential mosquito larvicide and can be used as a potent alternative to chemical insecticides in integrated pest management.

Background & Objectives: Mosquito-borne diseases significantly impact global health, particularly in tropical regions. While synthetic insecticides are currently employed to control mosquito vectors, their detrimental effects on ecosystems and persistence necessitate alternative control methods. Botanicals, owing to their diverse phytocompounds, offer potential for controlling and preventing vector-borne diseases by targeting insect eggs and larvae. This study aimed to evaluate the toxicity of Melissa officinalis and Rosmarinus officinalis extracts (methanolic and aqueous) against Aedes aegypti larvae, a vector of arboviruses. Materials & Methods: Total protein content in control and plant extract-exposed larval homogenates was estimated using bovine serum albumin as a standard. Acetylcholinesterase (AChE) and carboxylesterase assays were performed to determine larvicidal effects. Larval mortality was assessed after 24 hours of exposure. Results: Our findings revealed that the methanolic leaf extract of M. officinalis exhibited superior larvicidal activity (100% at 1000 ppm) compared to the methanolic R. officinalis extract (84±2. 45% at 1000 ppm). In contrast, the aqueous extracts of both plant species inferred no larvicidal activity. The LC50 and LC90 values for M. officinalis methanolic extract were 378. 7 ppm and 795. 8 ppm, respectively, whereas those for R. officinalis were 648. 9 ppm and 1152. 9 ppm, respectively. Furthermore, biochemical assays measuring total protein, acetylcholinesterase, α-carboxylesterase, and β-carboxylesterase activities were conducted for M. officinalis, corroborating and substantiating its larvicidal properties. Conclusion: This study demonstrates that the methanolic leaf extract of M. officinalis possesses significant larvicidal efficacy against A. aegypti. These findings suggest that this plant or its phytocompounds could serve as a bioinsecticide, offering a potential alternative to environmentally toxic and non-biodegradable synthetic insecticides.

Background: Derris elliptica extracts have a high larvicidal potential against the laboratory strain of Aedes aegypti larvae, but the effect on offspring larvae of pyrethroid-resistant strains of the species is lack understood. This study aimed to determine the larvicidal activity of the ethyl acetate extract of tuba root against the third-instar larvae of the Cypermethrin-resistant Ae. aegypti offspring. Methods: The experimental study occupied four levels of ethyl acetate extract of D. elliptica namely 10, 25, 50, and 100 ppm, and each level was four times replicated. As many as twenty of healthy third-instar larvae, offspring of Cypermethrin-resistant Ae. aegypti were subjected to each experiment group. Larval mortality rate and lethal concentration 50% subject (LC50) were calculated after 24 and 48 hours of exposure time. Results: Mortality of larvae increased directly proportional to the increase of extract concentration. Larval mortality rates after 24 and 48 hours of exposure were 40– 67. 5% and 62. 5– 97. 5%, and LC50 were 34. 945 and 6. 461ppm, respectively. Conclusion: The ethyl acetate extract of D. elliptica has the high effectiveness larvicidal potential against the thirdinstar larvae, offspring of the Cypermethrin-resistant Ae. aegypti. Isolation of the specific compound is necessarily done to obtain the active ingredient for larvicide formulation.

Background: To investigate the diversity of the genus Aedes present in the natural areas of Ardabil Province, north-west of Iran. Methods: This cross-sectional study was carried out from Apr to Oct 2016 in North-western of Iran. Thirty-three areas of 10 cities which are border areas were selected randomly. The larvae were collected 2 times in each month during the seasonal activities of mosquitoes and the larvae were identified morphologically according to the ap-propriate identification keys. Results: Overall, 694 larvae were collected from four counties, from which only 7. 2% were Aedes larvae. Three species of Aedes were identified which include Ae. caspius, Ae. vexans and Ae. flavescens. Aedes flavescens is re-ported from Ardabil Province for the first time. Conclusion: Aedes species were a high density in borderline of Iran and Azerbaijan. Therefore, the north parts of Ardabil Province are a suitable habitat for Aedes species mosquitoes. Care should be taken for vector control in the case of occurrence of any arboviruses transmitted by Aedes mosquitoes.