Entomological surveillance is one of the tools used in monitoring and controlling vector-borne diseases. However, the use of entomological surveillance for arboviral infection vector control is often dependent on finding infected individuals. Although this method may suffice in highly endemic areas, it is not as effective in controlling the spread of diseases in low endemic and non-endemic areas. In this study, we examined the efficiency of using entomological markers to assess the status and risk of arbovirus infection in Ghana, which is considered a non-endemic country, by combining mosquito surveillance with virus isolation and detection. This study reports the presence of cryptic species of mosquitoes in Ghana, demonstrating the need to combine morphological identification and molecular techniques in mosquito surveillance. Furthermore, although no medically important viruses were detected, the importance of insect-specific viruses in understanding virus evolution and arbovirus transmission is discussed. This study reports the first mutualistic relationship between dengue virus and the double-stranded RNA Aedes aegypti totivirus. Finally, this study discusses the complexity of the virome of Aedes and Culex mosquitoes and its implication for arbovirus transmission.

Blood-feeding arthropods, particularly ticks and mosquitoes are considered the most important vectors of arthropod-borne diseases affecting humans and animals. While feeding on blood meals, arthropods are exposed to high levels of reactive oxygen species (ROS) since heme and other blood components can induce oxidative stress. Different ROS have important roles in interactions among the pathogens, vectors, and hosts. ROS influence various metabolic processes of the arthropods and some have detrimental effects. In this review, we investigate the various roles of ROS in these arthropods, including their innate immunity and the homeostasis of their microbiomes, that is, how ROS are utilized to maintain the balance between the natural microbiota and potential pathogens. We elucidate the mechanism of how ROS are utilized to fight off invading pathogens and how the arthropod-borne pathogens use the arthropods’ antioxidant mechanism to defend against these ROS attacks and their possible impact on their vector potentials or their ability to acquire and transmit pathogens. In addition, we describe the possible roles of ROS in chemical insecticide/acaricide activity and/or in the development of resistance. Overall, this underscores the importance of the antioxidant system as a potential target for the control of arthropod and arthropod-borne pathogens.

The incorporation of saturated nitrogen-containing heterocycle 1,2,5-oxadiazinane into small molecules represents a compelling avenue in drug discovery due to its unexplored behavior within biological systems and incomplete protocols for synthesis. In this study, we present 1,2,5-oxadiazinane, an innovative heterocyclic bioisostere of piperizin-2-one and novel chemotype of the anti-schistosomal drug praziquantel (PZQ), which has been the only clinical drug available for three decades. PZQ is associated with significant drawbacks, including poor solubility, a bitter taste, and low metabolic stability. Therefore, the discovery of a new class of anti-schistosomal agents is imperative. To address this challenge, we introduce a pioneering method for the synthesis of 1,2,5-oxadiazinane derivatives through the cycloaddition of nitrones with N,N,N',N'-tetraalkyldiaminomethane in the presence of an IrIII complex photosensitizer. This transformative reaction offers a streamlined route to various kinds of 1,2,5-oxadiazinanes that is characterized by mild reaction conditions and broad substrate scope. Mechanistic investigations suggest that the photoredox pathway underlies the [3+3] photocycloaddition process. Thus, based on bioisosteric replacement, we identified a remarkable molecule as a new chemotype of a potent anti-schistosomal compound that not only exhibits superior solubility, but also retains the potent biological activity inherent to PZQ.