Larvicidal activity of ethanolic leaf and seed extract of Croton tiglium against Aedes aegypti

Aim and objectives: Mosquitoes are the transmitters of serious human diseases that cause millions of deaths every year. The use of synthetic insecticides causes harmful side effects to the environment and human health. So a natural alternative way is needed to solve this problem. Extracts from the various parts of plants like leaves, seeds, barks and roots can be used to control mosquitoes. This study aims to evaluate the larvicidal activity of ethanolic seed and leaf extracts of a traditionally used medicinal plant Croton tiglium, against Aedes aegypti, the vector of dengue fever. Material and methods: In this study, extracts from the dried leaf and seed powder of the Croton tiglium plant were extracted using ethanol in a soxhlet apparatus. Different concentrations were prepared from the extracts. Third instar larvae of Aedes aegypti were collected from the mosquito culture laboratory of the Life Sciences Department of Dibrugarh University. Prepared concentrations of the extracts were tested against the larvae of Aedes aegypti to evaluate the larvicidal activity by calculating percent mortality. Result: The ethanolic leaf and seed extracts of the selected plant were found effective against the larvae of Aedes aegypti. The 250 ppm concentration of both leaf and seed extracts showed the highest mortality of mosquito larva. The seed extract of this plant was found more effective in killing mosquito larva. Conclusion: From the study, it can be concluded that the ethanolic leaf and seed extracts of Croton tiglium possess larvicidal activity against Aedes aegypti. Hence, it could be useful in controlling mosquitoes without any harmful effects. However, further study and investigation will be needed to isolate and characterize bioactive components from this plant with larvicidal activity and the development of drugs for dengue from the components

The Effect of Lemongrass Leaves and Stalks Extracts using Methanol as The Eco-friendly Larvicides on Fourth Instar Aedes aegypti Larvae

BACKGROUND: Aedes aegypti is one of the most vicious mosquitoes, known for its role in several deadly diseases, including dengue fever and Zika. Several strategies have been developed over decades to prevent vector-borne diseases; one of them is insecticide to control the mosquito population. However, this strategy would not last long due to the elevation of resistance, environmental problem, and some issues regarding human health. Natural products have become major options to combat the glitches. Lemongrass (Cymbopogon citratus) has known for its toxic effect on mosquito larva. AIM: The objective of this study was to assess the effect of C. citratus extract against fourth instar of A. aegypti larvae. METHODS: Three extract concentrations, 2.5%, 5%, and 7.5%, were used. The larvicide activity was evaluated at 2, 4, and 6 h. Our data indicated that all concentrations contributed to increase larvae mortality. RESULTS: Lethal Concentration (LC) 50 and LC90 were achieved at 2.5% and 4.1% of extract, respectively. CONCLUSION: C. citratus extract has a larvicide activity against fourth instar of A. aegypti.

Risk Of Dengue Transmission In Urban Areas Of Malang, Indonesia

Background. Larvae monitoring through community participation is one of dengue prevention programs to control mosquito larvae. Entomology index could be an indicator of the existence of mosquito larvae in an area. This study aimed to determine the entomology index in the urban areas in Malang city and key container which could be the breeding ground of mosquito.Methods. This study was a surveillance study conducted in five subdistricts in Malang city from November 2017 to April 2018. A semi-structured questionnaire delivered using interviews to 400 respondents was used to explore the practice of Dengue prevention behavior. Observations were performed to examine the mosquito larva existence among the houses of health volunteers.Results. Density figure in Malang was indicated as moderate density that had range 2-5 . Blimbing subdistrict had the highest House Index (HI) value, which was 30.3% with Container Index (CI) value of 10.6% and Breteau Index (BI) value of 36,3 %. The most common positive Controllable Containers were bathroom tub/container (8.5%) and the water reservoir of a refrigerator (3%).Conclusion. Urban area in Malang has a moderate risk of transmitting dengue fever whose highest risk area was Blimbing subdistrict. There is need health promotion more or strict policy to the community also health volunteers to observe bathroom containers and water reservoir of refrigerator.

Determination of Oviposition, pH, and Salinity of Aedes aegypti's Breeding Places in Semarang Regency

Dengue Hemorrhagic Fever (DHF) is still a health problem in Indonesia. This is because DHF can cause decease, and the incidence is always increasing. Vector control efforts in Semarang Regency can be done by knowing mosquito bionomics, so one of the actions can be taken is to modify the environment, so that the Ae. aegypti mosquito feels uncomfortable about our environment. This type of research is pure experimental. In this research, mosquito larva will be the subject to be breeded using water with various degrees of acidity (pH) and salinity, then the ability to reproduce in various water with the pH and salinity levels is observed. The sample used was F1 larva originating from breeding places using ovitrap in Semarang Regency. Based on the results of the study showed that the most preferred container of the Ae. Aegypti mosquito for oviposition is a container made of plastic and can. The most optimal water pH for instar 2 larva breeding is water with a pH of 9, followed by water with a pH of 8 and 7. The most optimal water salinity for instar 2 larva breeding is water with a 0-6gr / l salinity.

Mosquito Nests Eradication through Monitoring the Mosquito Larva (Jumantik) by School Children in Preventing the Dengue Hemorrhagic Fever

Background: Dengue Hemorrhagic Fever (DHF) is still a major health problem in Indonesia. Community participation is a key component of DHF control. The group of schoolchildren is part of a group of people who can play a strategic role, considering the number is very much around 20% of the population. Through this Jumantik, the elementary school children are trained as a mosquito larva (jumantik) in their school. Objective: Establishment of larva monitoring group (Jumantik) and implementation of mosquito nest eradication activity at home and at school Method: A community service activity is conducted by recruiting and providing the training for Jumantik School Children and the teachers. Before the training, the students were given with the pre-test. After the training, the students followed the post-test and were given the mosquito eradication kit to undertake the mosquito larva monitoring at school and home. Result: As much as nine elementary students and three teachers were formed as jumantik volunteers from three different elementary schools namely Malewang, Palleko and Pangembang . The result of pre-test of 9 students, the average score of 8.67 (maximum points 15) with the highest score 11 and the lowest score 6. While the post test results obtained an average value of 11, 89 with the highest value 14 and the lowest value 10. The forms of activity for this program were: establishment of Jumatik school children, distribution of mosquito eradication kit, distribution of leaflet and stickers as the media of health promotion, provision of certificate of training of Jumantic school children and the teachers, the establishment of Plan of Action (POA) of the program and the production of second-hand good products. Conclusion and Suggestion: There are six activities that was implemented in this community service activity. It is suggested that the school to carry out routine activities according to the POA that has been agreed and the community health center can supervise the activity undertaken by the Jumantik school children. Keywords: Jumantik, Dengue Hemorrhagic Fever, school children, mosquito eradication