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  • Essay / Mosquitoes – The main important group of biting Diptera

    The main important group of biting Diptera are mosquitoes. Mosquitoes have long, slender bodies, needle-shaped mouthparts and legs. The wings sometimes have visible scale patterns. Some species of mosquitoes bite in the evening or morning and at night and some mosquitoes bite during the day. (Rozendaal, 1997). Many tropical diseases such as filariasis, malaria, dengue fever, dengu hemorrhagic fever, Japanese encephalitis and yellow fever etc. are transmitted by several species of mosquitoes. About 100 species among 3,000 species of mosquitoes are vectors of human diseases (Rozendaal, 1997; Rahuman et al., 2008; Arivoli and Tennyson, 2012). Lymphatic filariasis is transmitted by different species of mosquitoes, namely Culex, Anopheles and Aedes mosquito species. The infection usually occurs during childhood and causes hidden damage to the lymphatic system. Lymphatic edema, elephantiasis and scrotal swelling occur later in life and permanent disability of the patient is noted. Patients experience social, mental and financial losses that contribute to stigma and poverty, including physical ones. Worldwide, 947 million people in 54 countries suffer from lymphatic filariasis and need chemotherapy to prevent this neglected disease. Say no to plagiarism. Get a tailor-made essay on "Why violent video games should not be banned"?Get the original essayIn 2000, more than 120 million people were infected, and approximately 40 million were disfigured and disabled by this terrible disease. Globally, those affected by lymphatic filariasis included 25 million men with hydrocele and more than 15 million people with lymphedema. Manifestations of chronic diseases affect approximately 36 million people. Lymphatic filariasis is caused by nematodes (Filariodidea family). There are 3 types of filarial worms: Wuchereria bancrofti (causing 90% of filariasis), Brugia malayi (causing most other cases), and Brugia timori (which also causes disease). The immune system of an infected person is destroyed by the adult worms. Adult worms produce millions of microfilariae that circulate in human blood. When mosquitoes ingest blood, the microfilariae enter the mosquito's body. The microfilariae transform into infectious larvae within the mosquito. When infected mosquitoes bite people, mature microfilariae enter the lymphatic vessels of the human body and develop into adult worms, allowing the transmission cycle to continue (WHO, 2017). In 2000, WHO launched the Global Program to Eliminate Lymphatic Filariasis (GPELF). In 2012, WHO reconfirmed the target date for achieving elimination of the neglected disease, filariasis, by 2020. WHO recommended mass drug administration (MDA) to stop the spread of filariasis. infection and eliminate it. of lymphatic filariasis (LF). MDA consists of a combined dose of 2 drugs administered annually as preventative chemotherapy measures and these drugs are 400 mg albendazole and ivermectin (150-200 mcg/kg) or with diethylcarbamazine citrate (DEC) ( 6 mg/kg). These drugs have a weak effect on adult Wuchereria bancrofti but are very effective on microfilariae. Between 2000 and 2015, 6.2 billion treatments were provided to more than 820 million people to prevent the spread of the disease in many places. Cambodia, Niue, Sri Lanka, Vanuatu, Maldives and Cook Islands reached the elimination targetfilariasis. The WHO recommended strategy for the elimination of lymphatic filariasis has been successfully implemented by thirteen additional countries. In 54 countries, chemotherapy is still necessary to eradicate the disease. (WHO, 2017).In India, Wuchereria bancrofti and Brugia malayi are two causative agents of lymphatic filariasis. But 95% of filariasis is caused by Wuchereria bancrofti and 5% by the parasite Brugia malayi. Brugia malayi is widespread in the states of Tamil Nadu, Andra Pradesh, Kerala, Odisha, West Bengal, Madhya Pradesh and Assam. India alone accounts for 40% of the global burden of disease (Michael et al., 1996). Seventeen states and six Union Territories of India have been identified as endemic, with around 553 million people at risk of infection, of which around 146 million live in urban areas and the rest of the population lives in areas rural. In India, it is estimated that about 31 million people carry microfilariae and more than 23 million people suffer from manifestations of filarial disease (WHO, 2005). The highest endemicity was found in Bihar (over 17%), followed by Kerala (15.7%) and Uttar Pradesh (14.6%). Endemicity of 10% was found in the states of Andhra Pradesh and Tamil Nadu. The lowest endemicity was observed in Goa (less than 1%), followed by Lakshadweep (1.8%), Madhya Pradesh (above 3%) and Assam (around 5%). B. malayi is widespread in the states of Kerala, Tamil Nadu, Andhra Pradesh, Orissa, Madhya Pradesh, Assam and West Bengal (Regu et al., 2005; National Control Program of vector-borne diseases, 2010). Mosquito control is essential for eradication. mosquito-borne diseases, thereby improving environmental quality and public health. The main tool and technique for mosquito control is the application of synthetic insecticides. In the past, control measures for mosquito vectors relied on the frequent and indiscriminate use of synthetic insecticides based on chemicals, namely carbamates, organochlorines, organophosphates and pyrethroids (Liu et al., 2006). . Indiscriminate use of insecticides has resulted in increased selection pressure on mosquitoes, leading to the development of insecticide-resistant varieties among mosquitoes (Raghvendra, 2002; Kumar et al., 2012). An insecticide resistant variety in Culex quinquefasciatus against cyhalothrin, fenthion and cypermethrin, temephos, has been developed. Insecticide residues enter the ecosystem through the food chain. The adverse effects of the use of insecticides have therefore necessitated the research and development of indigenous, biodegradable and environmentally friendly methods to control mosquito species (Tikar et al., 2008). Thus, in recent years, the use of many old synthetic insecticides to control mosquitoes has been limited due to the high cost of pesticides, concern for environmental sustainability, lack of new pesticides, adverse effects on human health and other animals, the rate of increase in mosquito rates. biological amplification, their non-biodegradable nature and the development of insecticide-resistant varieties (Brown, 1986; Russell, 2009). Accordingly, the Environmental Protection Act of 1969 developed a number of rules and regulations to control the application of chemical control agents. in nature (Bhatt and Khanal, 2009). Since ancient times, even before the discovery of synthetic insecticides, many herbal products have been used as insecticidesnatural. Plants such as pyrethrum, chrysanthemum, Derris, Quassia, nicotine, turpentine, hellebore, azadirachtin, etc. were used as botanical insecticides before DDT (Shaalan et al., 2005). One approach to controlling mosquito-borne diseases is to interrupt disease transmission by killing, using repellents, or using larvicides to reduce large-scale larval mortality in vector breeding centers. Currently, mosquito control strategies have failed due to the development of increasingly insecticide-resistant varieties (Brown, 1986; Georghion and Lagunestjida, 1991; WHO, 1992; Kelm et al., 1997; Su and Mulla, 1998; Gericke et al., 2002). ; Haegreaves et al., 2003). Various organophosphates (Temiphos and Fenthion) and insect growth regulators (Diflubenzuron and Methoprene) are widely used as larvicides to control mosquitoes (Rozendaal, 1997). These synthetic pesticides have caused the development of a variety of resistant mosquitoes, ecosystem imbalance, and damage to mammals, including humans (Georghiou and Langunes-tejeda et al., 1991). The best alternative way to prevent these problems could be the use of botanical pesticides.insecticides, which are degradable in nature and renewable in source. Plants have co-evolved with insects with the production of secondary metabolites for their chemical defense mechanisms. More than 2000 plant species have been identified that produce secondary metabolites of value for biological pest control programs and among them, 344 species have been identified with significant activity against mosquitoes (Remia and Logaswamy, 2009). Larvicidal, pupicidal, adulticidal, egg-laying activity, smoke toxicity or repellent activities of plant species belonging to different families, namely Asteraceae, Labiatae, Cladophoraceae, Miliaceae, Rutaceae Solanaceae, Oocystaceae, Caricaceae, etc. have been identified (Shaalan et al., 2005; Rawani et al., 2012; Rajkumar et al., 2005; Singha et al., 2011). Even before the discovery of synthetic organic insecticides, more than 50 years ago, certain herbal products, namely anabasine and lupinine, the alkaloids of the Russian grass, Anabasis aphylla; nicotine from the leaves of Nicotiana tabacum; Rotenone from Derris eliptica and pyrethrums from Chrysanthemum cinererifolium flowers have been used as herbal insecticides for vector control due to their low cost, biodegradable nature, environmental safety, etc. (Campbell et al., 1993; Zubairi et al., 2004; Hartzell and Willcoxon, 1941) Hartzell and Willcoxon (1941) worked with 150 plant species to observe toxicities against mosquitoes and several of them showed their efficiency. Sarita et al. 2012 collected 15 plant species from local areas of New Delhi, India and obtained extracts of different solvents from different plant parts. Each extract was examined to explore its effectiveness as a mosquito larvicidal agent against early stages of the fourth instar of the dengue vector, Aedes aegypti. 10 plants showed larvicidal potential and further evaluation of the larvicidal efficacy of the extracts established that Lantana camara hexane leaf extract was the most effective extract with a significant LC50 value of 30.71 ppm, while Phyllanthus emblica fruit extract was found to be the least effective with a significant larvicidal value of 30.71 ppm. LC50 value of 298.93 ppm. Ranaweera, 1996 examined some plants from Sri Lanka to observelarvicidal activity of mosquitoes and out of 53 plant species tested, 18 plants showed larvicidal activity against Culex quinquefasciatus mosquito species. Mondal et al., 2016 experimented on 32 plant species and among them, 8 plants showed larvicidal activity by crude extracts against Culex quinquefasciatus mosquito species. Amer and Mehlhorn (2006) showed the repellent power of forty-one essential oil preparations against Aedes, Anopheles and Culex mosquitoes. Jantal et al. (2003) evaluated 17 methanol extracts and 9 essential oil preparations of Malaysian plants for their larvicidal activities against Aedes aegypti. Roark, 1947 described approximately 1,200 plant species with insecticidal potential. Sukumar et al., 1991 listed and discussed 344 plant species that exhibited only mosquitocidal activity. Ghosh et al., 2012 reviewed a large number of plants with mosquitocidal effectiveness. The insecticidal activity of plant extracts varies depending on the plant species, mosquito species, geographical varieties, part of the plant, extraction methodology used, and polarity of solvents used during extraction. A wide range of plants from shrubs, herbs and large trees have been used for extraction to obtain toxic phytochemicals to kill mosquitoes. Phytochemicals are extracted either from whole plants like small herbs or from different parts i.e. leaves, fruits, barks, stems, roots, etc. larger plants or trees. In all cases, the most toxic substances are used to control mosquitoes (Shaalan et al., 2005). Secondary metabolites, present in plants, act as a defense system against pest/insect attacks. The presence of secondary metabolites of the plant namely steroids, alkaloids, terpenoids, phenolic compounds, flavanoids etc. act as molting hormones, juvenile hormone mimics, anti-baits, egg-laying deterrents, repellents, growth inhibitors, anti-molting hormones, attractants, etc. and these properties of secondary metabolites responsible for the biological activity of plant extracts against target pests (Champagne et al., 1986). The Annonaceae family is made up of trees, shrubs or rarely lianas. The family includes 108 (accepted) genera and nearly 2,400 known species. Plants of the Annonaceae family grow mainly in the tropics; nearly 900 species grow in the neotropical; 450 species in the Afrotropical zone; some species in temperate regions and the other species in Indomalayan. Annona reticulata Linn. belongs to the Annonaceae family. It is also known as Custard Apple, Sugar Apple, Sweet Apple, Ramphalam, Sitaphala, Sarifa, etc. Its native land is South America and the West Indies. It is widely distributed in India, Bangladesh, Pakistan and Thailand (Kaleem, 2006; Satyanarayana, 2013). It is a small deciduous and semi-evergreen tree measuring 8 to 10 meters high, with a spreading or rounded crown and a trunk measuring approximately 25 to 35 cm in diameter. The leaves are glabrous, straight and pointed at the apex and wrinkled in some varieties. The leaves are narrow-lanceolate, alternate and deciduous in nature, with conspicuous veins and the leaves are approximately 10 to 20 cm long and 2 to 5 cm wide. The flowers are yellow-green, fragrant in drooping, slender clusters, with 3 narrow, fleshy outer petals 2 to 3 cm long that are never fully open. The fruits vary in structure, such as spherical, heart-shaped, irregular or oblong and measure approximately 8 to 16,.