Role of Virulence Factors in Salmonellosis

Abstract

Salmonella is a genus of bacteria that cause enteric fever (typhoid and paratyphoid) and gastroenteritis in all parts of the world. Salmonella bongori and Salmonella enterica are the species with more than 2600 serovars. An estimated 535,000 cases of non-typhoidal salmonella invasive disease occurred in 2017. S. enterica serovar Typhimurium and S. enterica serovar Enteritidis are the two most common serovars of Salmonella that cause food borne gastroenteritis. Salmonella organisms are widely distributed in nature. The species of Salmonella has been detected from a variety of food stuffs including vegetables, salad green, fruits, poultry birds, meat and their products. Annually, a number of outbreaks are reported due to consumption of contaminated water and food. In African countries invasive nontyphoidal Salmonella have emerged as a major cause of bloodstream infection. The main risk factors for children are immunocompromised status of HIV infection and malnutrition. The major virulent genes are located in Salmonella pathogenicity islands. A variety of virulence factors play role in the pathogenesis. The capsular polysaccharide is an important virulence factor in preventing phagocytosis, masking from antibodies and inhibiting of complement fixation. Infection by serovars of non-typhoidal Salmonella induce Th1 immune response. Multiple drug resistant Salmonella species pose a major global public health concern. It is essential to keep continuous monitoring of the food stuff, food processing stages and food handlers for the presence of both typhoidal and non-typhoidal Salmonella.

Keywords: Salmonellosis, non-typhoidal salmonella, gastroenteritis, virulence factors, pathogenesis, S. enterica

Cite this Article: Durgadas Govind Naik, Tharani Subarmaniam. Role of Virulence Factors in Salmonellosis. International Journal of Molecular Biotechnology. 2019; 5(2): 30–36p.