Introduction about Salmonella - Assignment Example

In the early periods of the 19th century, typhoid was basically defined on the basis of its symptoms and clinical signs. Literally, every enteric fever was categorized as typhoid. During 1880s, Eberth became the first person to observe the typhoid bacillus in parts of the spleen as well as in the mesenteric lymph nodes from a person who had succumbed to typhoid (Todar, 2009). Robert Koch later confirmed Eberth’s discovery and cultivated the bacterium in 1881. In 1896, it was established that typhoid bacillus agglutinated the bacterial cells causing typhoid using the serum of animal blood.

The same result replicated in patients suffering from typhoid and thus, serodiagnosis of typhoid became a possibility in 1896 (Todar, 2009). Proper development of complete genome ensures effective classification of disease-causing organisms (pathogens) and their hosts. The classification of the genus salmonella has undergone considerable changes over many years as the methods of identification methods keep improving with time (Liu, 2011). In 1946, Kaufmann White developed a scheme that enabled distinguishing of Salmonella serovars based on their O, H as well as Vi antigens (Todar, 2009).

According to Warrell et al. (2005), the genome of Salmonella enterica serovar Typhi (S. . The impacts of Salmonella enterica serovarTyphi range from health to economic devastations. When an individual consumes contaminated water, the symptoms of typhoid fever are likely to manifest after a short while. Typhoid fever is usually connected with systemic fever, loss of appetite, nausea or vomiting, which is usually followed with diarrhea. If left untreated for a very long period of time, the disease could cause death in humans.

Salmonella enterica serovar Typhi is most prevalent in developing nation where poor sanitation leads to contamination of water for drinking. As such Salmonella enterica serovarTyphi is one of the contributors to high health spending in different parts of the world. According to Crump, Luby and Mintz (2004), typhoid fever is a burden worldwide and causes about 16 million illnesses and more than 600, 000 fatalities every year. Introduction Closest Relatives of Salmonella Enterica Serovar Typhi and Their Features There is no clear understanding of the genetic basis of the distinctions in host tropism that exist between serovars and wide host range.

The genetic changes that come with evolutionary changes in the serovars include the build-up of mobile components and pseudogenes together with the arrangement of chromosomes and deletion that causes the reduction in the genome (Porwollik, 2011). One close relative of Salmonella enterica serovar Typhi is Salmonella enterica serovar Typhimurium. According to Todar (2009), Salmonella enterica serovar Typhimurium is “a Gram-negative facultative rod-shaped bacterium in the same proteobacterial family as Escherichia coli, the family Enterobacteriaceae, trivially known as "enteric" bacteria” (Todar,