Botanical Products in the Treatment and Control of Schistosomiasis: Recent Studies and Distribution of Active Plant Resources According to Affected Regions.

Schistosomiasis, a parasitic disease caused by trematodes of the genus Schistosoma, is the second most prevalent parasitic disease in the world. It affects around 200 million people. Clinical treatment, prophylaxis, and prevention are performed in countries susceptible to schistosomiasis. In the pharmacological treatment for an acute form of schistosomiasis, the use of antiparasitics, mainly praziquantel, is more common. As an alternative way, prevention methods such as reducing the population of intermediate hosts (mollusks) with molluscicides are important in the control of this disease by interrupting the biological cycle of this etiological parasite. Despite the importance of pharmacological agents and molluscicides, they have side effects and environmental toxicity. In addition, they can lead to the development of resistance enhancing of parasites, and lead to the search for new and effective drugs, including resources of vegetal origin, which in turn, are abundant in the affected countries. Thus, the purpose of this review is to summarize recent studies on botanical products with potential for the control of schistosomiasis, including anti-Schistosoma and molluscicide activities. In addition, species and plant derivatives according to their origin or geographical importance indicating a possible utility of local resources for countries most affected by the disease are presented.

Nanoemulsions of Essential Oils: New Tool for Control of Vector-Borne Diseases and In Vitro Effects on Some Parasitic Agents.

The control of infectious/parasitic diseases is a continuing challenge for global health, which in turn requires new methods of action and the development of innovative agents to be used in its prevention and/or treatment. In this context, the control of vectors and intermediate hosts of etiological agents is an efficient method in the prevention of human and veterinary diseases. In later stages, it is necessary to have bioactive compounds that act efficiently on the agents that produce the disease. However, several synthetic agents have strong residual effects in humans and other animals and cause environmental toxicity, affecting fauna, flora and unbalancing the local ecosystem. Many studies have reported the dual activity of the essential oils (EOs): (i) control of vectors that are important in the cycle of disease transmission, and (ii) relevant activity against pathogens. In general, EOs have an easier degradation and cause less extension of environmental contamination. However, problems related to solubility and stability lead to the development of efficient vehicles for formulations containing EOs, such as nanoemulsions. Therefore, this systematic review describes several studies performed with nanoemulsions as carriers of EOs that have larvicidal, insecticidal, repellent, acaricidal and antiparasitic activities, and thus can be considered as alternatives in the vector control of infectious and parasitic diseases, as well as in the combat against etiological agents of parasitic origin.