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Background: Malaria has remained the most dreadful vector-borne disease; hence, vector control is the most affordable and achievable approach to mitigate the disease burden. Due to the emergence of resistance and environmental pollution, herbal larvicides are considered an alternative to chemical types. Also, nanotechnology has been proposed as a promising solution to improve the efficiency of plant larvicides. This study aimed to develop an effective herbal larvicide. Methods: The chemical composition of Elettaria cardamomum essential oil (EO) was first investigated. Nanoliposomes containing the EO were then prepared using the ethanol injection method. After that, the larvicidal efficacy of the EO and its liposomal state were compared against Anopheles stephensi in laboratory conditions. Results: Alpha-terpinyl acetate (77.59%), eucalyptol (4.38%), nerolidol (2.96%), linalool (1.77%), and limonene (1.69%) were the five major compounds of the EO. Nanoliposomes containing the EO with a particle size of 73±5 nm and a zeta potential of -16.3±0.8 mV were prepared. Additionally, the ATR-FTIR analysis verified the successful loading of the EO into nanoliposomes. The larvicidal activity of nanoliposomes exhibited remarkable potency, with an LC50 value of 14.35 (10–18) µg/mL, significantly more potent than the non-formulated EO, which had an LC50 value of 33.47 (28–39) µg/mL against Anopheles stephensi larvae. Conclusion: The nanoliposomes containing E. cardamomum EO showed promising efficacy against An. stephensi larvae. It could thus be considered for further application against other species of mosquitoes. [ABSTRACT FROM AUTHOR]

Head lice (Pediculus humanus capitis) are one of the most common insects causing infestations in humans worldwide, and infestation is associated with adverse socio-economic and public health effects. The development of genetic insensitivity (e.g., target site insensitivity = knockdown resistance or kdr) to topical insecticides has impaired effective treatment. Therefore, this study was undertaken to review and meta-analyze the frequency of pyrethroid resistance in treated head louse populations from the beginning of 2000 to the end of June 2021 worldwide. In order to accomplish this, all English language articles published over this period were extracted and reviewed. Statistical analyses of data were performed using fixed and random effect model tests in meta-analysis, Cochrane, meta-regression and I2 index. A total of 24 articles from an initial sample size of 5033 were accepted into this systematic review. The mean frequency of pyrethroid resistance was estimated to be 76.9%. In collected resistant lice, 64.4% were homozygote and 30.3% were heterozygote resistant. Globally, four countries (Australia, England, Israel, and Turkey) have 100% kdr gene frequencies, likely resulting in the ineffectiveness of pyrethrin- and pyrethroid-based pediculicides. The highest resistance recorded in these studies was against permethrin. This study shows that pyrethroid resistance is found at relatively high frequencies in many countries. As a result, treatment with current insecticides may not be effective and is likely the cause of increased levels of infestations. It is recommended that resistance status be evaluated prior to insecticide treatment, to increase efficacy.

Objective: To examine the fauna of rodents as zoonotic cutaneous leishmaniasis reservoir hosts in Zarqan County, Fars Province, south of Iran, during 2012. Methods: During 2012, wild rodents from different parts of this region were caught by Sherman traps and checked by the examination of liver and spleen smears, for Leishmania infection, to see which species were acting as reservoir hosts; the slides were then processed to extract DNA for molecular test using PCR assay. Results: From 108 rodent species caught, 63% were male and 37% identified as female. Meriones libycus was the most abundant species caught (80.5%) and 5.7% of them were found to be smear-positive for Leishmania amastigotes. The other species were Rattus rattus (14.8%) and Mus musculus (4.7%), but none of them were found positive. Leishmania infection was observed in male and female samples microscopically. Moreover, molecular results revealed Leishmania major in three male and two female specimens. Conclusions: Based on our knowledge, Meriones libycus is incriminated as the main reservoir hosts of Leishmania major in the rural area of Zarqan.