Abstract
Plant-based repellents have been applied for generations in traditional practice as a personal protection approach against different species of Anopheles. Knowledge of traditional repellent plants is a significant resource for the development of new natural products as an alternative to chemical repellents. Many studies have reported evidence of repellant activities of plant extracts or essential oils against malaria vectors worldwide. This systematic review aimed to assess the effectiveness of plant-based repellents against Anopheles mosquitoes. All eligible studies on the repellency effects of plants against Anopheles mosquitoes published up to July 2018 were systematically searched through PubMed/Medline, Scopus and Google scholar databases. Outcomes measures were percentage repellency and protection time. A total of 62 trials met the inclusion criteria. The highest repellency effect was identified from Ligusticum sinense extract, followed by citronella, pine, Dalbergia sissoo, peppermint and Rhizophora mucronata oils with complete protection time ranging from 9.1 to 11.5 h. Furthermore, essential oils from plants such as lavender, camphor, catnip, geranium, jasmine, broad-leaved eucalyptus, lemongrass, lemon-scented eucalyptus, amyris, narrow-leaved eucalyptus, carotin, cedarwood, chamomile, cinnamon oil, juniper, cajeput, soya bean, rosemary, niaouli, olive, tagetes, violet, sandalwood, litsea, galbanum, and Curcuma longa also showed good repellency with 8 h complete repellency against different species of Anopheles. Essential oils and extracts of some plants could be formulated for the development of eco-friendly repellents against Anopheles species. Plant oils may serve as suitable alternatives to synthetic repellents in the future as they are relatively safe, inexpensive, and are readily available in many parts of the world.
Highlights
Mosquito-transmitted diseases remain a main source of illness and death [1]
Eligibility criteria Studies were included in the present systematic review if they met these criteria: (i) full-text publication was written in English, (ii) inspected the repellency effects of plant extracts and essential oils against malaria vectors, Anopheles spp. mosquitoes, and, (iii) reported the percentage of repellency or complete protection time
When focusing on Anopheles subspecies, there were only a few publications indicating the efficacy of each plant, which resulted in a difficulty to reach a robust conclusion regarding the best herbal candidates to develop new commercial repellents
Summary
Mosquito-transmitted diseases remain a main source of illness and death [1]. Despite decades of malaria control efforts, malaria continues to be a major worldwide public health issue with 3.3 billion persons at risk in 106 countries and territories in the tropical and subtropical areas [2]. Eligibility criteria Studies were included in the present systematic review if they met these criteria: (i) full-text publication was written in English, (ii) inspected the repellency effects of plant extracts and essential oils against malaria vectors, Anopheles spp. mosquitoes, and, (iii) reported the percentage of repellency or complete protection time. The 20% oil solution of olive in the study conducted by Amer et al [6], with a mean percentage of repellency (71.4%) and complete protection time against An. stephensi for 8 h, had a good effectiveness in preventing An. stephensi mosquitoes. The 20% oil solution of myrtle in the study conducted by Amer et al [6], with mean percentage repellency of 42.8% and complete protection time against An. stephensi for 6.5 h, had a good effectiveness in preventing Anopheles mosquitoes. Other studies found that turmeric oil repels An. dirus for 6 h [44] and An. minimus [45] for 1 h
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have