Nano- and microformulated botanicals for managing ticks and mites of medical and veterinary importance: Past, present, and future

Developing effective and sustainable green solutions for managing arthropod pests and vectors is a timely challenge. The present review is dedicated to mites and ticks (Acari), species which represent a burden for human and animal health. The focus is on hard ticks (Ixodidae), primarily belonging to the genera Haemaphysalis spp., Hyalomma spp., and Rhipicephalus spp., house dust mites Dermatophagoides spp., stored-product mites Tyrophagus putrescentiae and Acarus siro, various strains of the itch mite Sarcoptes scabiei, the poultry red mite Dermanyssus gallinae, and the main ectoparasitic mite of honeybees Varroa destructor. We overviewed all the nano- and microemulsions and capsules loaded with essential oils, plant extracts, and/or singular compounds applied as toxicant or repellent treatments to manage such pests. Additionally, we explored current knowledge about the effectiveness of metal nanoparticles obtained through green synthesis routes by exploiting phytochemicals in botanical extracts. For all the products, we reported their mean particle size, tested formulation, efficacy, and when available, mode of action, comparison with synthetic acaricides, and non-target effects. Future challenges involve the need to improve the synthesis technologies and storage conditions of the different formulations; scaling up the production is necessary too to achieve lower prices and wider distribution. Notably, research on S. scabiei and V. destructor is required, as these species are extremely overlooked when compared to hard ticks and other mites.