**6. Conclusion**

Globally, Salmonellosis is the main cause of bacterial disease in all living creatures. All over the world it is posing very serious public health concerns and compromising the yield and output of animal husbandry production. The effort of isolating, identifying, and reporting *Salmonella* serotypes must continue for diagnostic, therapeutic, and public health objectives, despite the fact that the nomenclature for *Salmonella* is constantly evolving and the argument over the naming for the type species is still ongoing. *Salmonella* outbreaks have been linked to a variety of foods, and researchers are scrambling to figure out how this infection impacts humans and animals. This infection is a leading source of morbidity and mortality worldwide, with the host immune response differing depending on nature of infection. The genetic makeup of *Salmonella* made it possible for its strains to adapt to different environmental conditions. The implications of this infectious disease in humans vary depending on its serotype and the health level of the human host. Thus for better understanding the genetics of *Salmonella* and to investigate the mechanisms that contribute to pathogenesis evolution, a lot of work has been done. Occurrence of two different, potentially complementary evolutionary approaches to host range and virulence were evaluated using genome sequencing of *Salmonella* serovars. It includes horizontal gene transfer, gene loss which actually affects its ability to colonize. Gene acquisition by horizontal transfer (associated with SPIs, transposable elements, phages, and plasmids) and gene loss or loss of function, which affects host range. In spite of the presence a greater amount of research findings related to *Salmonella* infection and pathogenesis mechanism in host animals, several key queries remain intact *viz* the exact role of virulence genes and genomic islands of particular serovar in animal models. Thus the need of hour is to have an in depth understanding of *Salmonella* pathogenesis for developing intervention strategy to minimize the disease's prevalence and spread, as well as assisting in the production of novel drugs and treatments which might lead to improved treatment of Salmonellosis in living creatures.
