The curious tale of how crocodiles farmed for designer leather handbags are helping to develop human anti-arboviral vaccines

Most residents of industrialised nations in temperate climatic zones know mosquitoes to be an irritant; those blood-sucking pests that can blight a summer barbeque or family picnic. However, for people living in tropical and subtropical regions of the world, mosquitoes carry the threat of transmission of pathogens responsible for debilitating and often life-threatening blood-borne infectious diseases (Randolph and Rogers, 2010). Chief among these is malaria, caused by the protozoan parasite Plasmodium, and transmitted between people by the infectious bite of mosquitoes belonging to the Anopheles genus (Satapathy and Taylor-Robinson, 2016). Also, noteworthy are so-called arthropod-borne viruses, arboviruses, which are defined as viruses that replicate in both vertebrate host and invertebrate vector and which are transmitted between vertebrate hosts by biting arthropods (such as mosquitoes, ticks, sandflies and midges). Among their number are included the aetiological agents of such global infections as dengue, yellow fever, chikungunya, Japanese encephalitis and Zika that present a significant public health risk worldwide (Wilder-Smith et al., 2017). These viruses are transmitted from person to person by various species of Aedes mosquito. These insects bite not only humans but a whole spectrum of animals – other mammals but also birds and reptiles, each of which acts as a reservoir host that enables the arbovirus to be sustained in the environment (Gyawali et al., 2017a).