Salmonella †description, pathogenesis, symptoms Essay

Salmonella – description, pathogenesis, symptoms Salmonella is a gram-negative bacillus that causes inflammation of the GI tract and in some cases, if the immune response is not sufficiently powerful and treatment is not administered, can become systemic and cause even more serious conditions throughout the body. After ingestion, these bacteria cause infection by invading the epithelial cells of the small intestine and macrophages. Though there are more than two thousand different subspecies of Salmonella, few of them are able to cause serious conditions in humans—for most, the disease resolves itself in a matter of days. Those who are most affected by Salmonella infection are infants, the elderly, and people with compromised immune†¦show more content†¦A bacterial disease of growing importance to the populace, 2 salmonella is a specialized invader of the gastrointestinal system that can cause a variety of painful conditions of varying severity. The bacteria known as Salmonellae are gram-negative, rod-shaped bacilli that belong to the family Enterobacteriacea—they are typically anaerobic, unable to form spores, and motile, or able to move around spontaneously. An important characteristic of the Salmonella bacteria is that they are able to grow and multiply outside living host organisms, thus having greater survival chances than otherwise (Gray and Fedorka-Cray 56). The bacteria can have a combination of three antigens: the O antigen, H antigen, and Vi antigen. The O antigen is located in the cell wall of the bacterium, and each salmonella bacillus may posses 2 or more O antigens on its surface. Also, the H antigen is a flagellar antigen that can be destroyed by heat and enables the motility of the Salmonella bacterium (Slack and Snyder 295). The last antigen is known as the Vi antigen because this antigen is related the virulence of the bacterium. As a capsular antigen, its presence enhances the virulence of the bacterium that has it—of all the sub-species of Salmonella, only two, Salmonella enterica serovar (S.) typhi and S. choleraesuis, have the Vi antigen (296). Depending on whether the type of Salmonella has one of