Endosymbiont bacterium Wolbachia: Emerged as a weapon in the war against mosquito born diseases

Because of climate change and failure of the existing methods of control of vector borne diseases and vector are increasing. Mosquito species are the main vectors of human pathogens causing malaria, dengue, filariasis, chikungunya, yellow fever and West Nile. There are no well-organized methods and tools of controls of vector and vector borne diseases, since no efficient vaccines or drugs are available. Despite years of intense effort to control them, many of these diseases are increasing in prevalence, geographical distribution and severity, and options to control them are limited. Currently, efforts focused on the control of vector populations. During recent years, the endosymbiont bacterium has been well-documented and has led to suggestions that these could be used to control pests and therefore diseases. Wolbachia is perhaps the most renowned insect symbiont, primarily due to its ability to manipulate insect reproduction and to interfere with major human pathogens therefore providing new avenues for pest control. Wolbachia are common intracellular bacteria that are found in arthropods and nematodes. These alphaproteobacteria endosymbionts are transmitted vertically through host eggs and alter host biology in diverse ways, including the induction of reproductive manipulations, such as feminization, parthenogenesis, male killing and sperm–egg incompatibility. Wolbachia strains can invade and sustain themselves in mosquito populations, reduce adult lifespan, affect mosquito reproduction and interfere with pathogen replication. Wolbachia can also provide direct fitness benefits to their hosts by affecting nutrition and development, influencing fecundity or oogenesis and providing resist­ance to pathogens. For instance, infection of Anopheles gambiae with both wMelPop and wAlbB reduced the oocyst burden of Plasmodium falciparum, compared to uninfected control mosquitoes. In addition, similar study observed that the wMelPop strain inhibited development of Plasmodium berghei; however, the wAlbB strain was found to enhance development of P. berghei.