IndexPathologyResponse and TreatmentEpidemiologySocio-Political-Economic ConsiderationsWorks CitedIn the early 1900s, New York state was a hot spot for typhoid fever epidemics. George Sober, a sanitary engineer, attributed these outbreaks to a woman, a cook named Mary Mallon. Mallon was the first described case of a healthy carrier of Salmonella typhii, the bacteria that causes typhoid fever, and showed no symptoms but harbored the bacteria within her. Over the course of his career, Mallon is believed to have infected one hundred and twenty-two people and caused the deaths of at least five people. Her name eventually became associated with any person who willingly or unwillingly infected others with a disease, nicknamed "Typhoid Marys". Typhus is just one of several diseases caused by the Salmonella genus, which will be described in this article. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay Salmonella, a genus that is part of the non-coliform group Enterobacteriaceae, is a bacillus-shaped bacterium 2-5 μm long and 0.7-1.5 μm in diameter, arranged in pairs or singles. They have peritrichous flagella, flagella that cover their entire body, making them a motile species. Salmonella is gram-negative and stains red during the GRAM stain test. Salmonella species are facultative anaerobes, capable of generating ATP in the presence or absence of oxygen. Salmonellae are chemotrophic organisms, that is, organisms that obtain their energy through the use of organic materials in oxidation and reduction reactions. The first major Salmonella outbreak appears to have occurred in Germany, where meat ingested from a diseased cow caused 50 people to become infected, and one man died. Salmonella typhimurium, corresponding to the same bacterium isolated from cow meat, was found in the blood and spleen tissue of the deceased man. Foodborne epidemics continued to be the leading cause of disease in Europe during the 20th century, but in the United States most epidemics involved bacteria that had a reservoir species. It was not until 1969 that these epidemics limited to reservoir species became rare in the United States. The reason for the decline is believed to be a major change in sanitation. Wastewater disposal techniques were refined, drinking water began to be treated and the hygiene of agricultural companies was improved. The typical clinical disease of the time, typhoid fever, was replaced by gastroenteritis and most epidemics began to appear in hospitals. In the 1970s, Salmonella's mode of transmission changed once again. Rather than being largely isolated to hospitals, large outbreaks have been attributed to infected foods, mainly animal-based foods from otherwise healthy animals carrying Salmonella. In the 1990s, internally contaminated eggs from hens with infected ovaries caused a rapid increase in Salmonella outbreaks. Pathology Salmonella bacteria cause a variety of diseases, including gastroenteritis, enteric fever, septicemia, and typhoid fever. Most bacteria enter the body through the ingestion of contaminated foods, where they then infiltrate the ileum, colon, and intestinal epithelium. After reaching the epithelium, the organisms multiply intracellularly and spread to the lymph nodes, where they can then reach the rest of the body through the systemic circulation (Giannella, 1996). Multiplication within the intestine causes an inflammatory response and hypersecretion of fluids. Salmonella can survive inside the lysosomes of macrophages. Some strains ofSalmonella can produce an intoxicating enterotoxin. Salmonella causes acute inflammation in the intestines and can also create ulcers. Damage to the intestine can be caused by the release of proinflammatory cytokines synthesized by epithelial cells. A condition called salmonellosis, or gastroenteritis, occurs in a large number of Salmonella serotypes, causing inflammation in both the large and small intestine, as well as diarrhea, vomiting, abdominal cramps, headache, and fever. Symptoms usually last a few days to a week. Salmonellosis is contracted through ingestion of contaminated food, handling eggs and raw poultry, or contact with reservoir animals. Serotype typhi causes typhoid fever, a more serious illness characterized by high fever, abdominal pain, muscle aches, lethargy, and skin rashes. Untreated typhoid infections cause mortality in up to 10% of cases. The Widal test is an inexpensive agglutination test used for the diagnosis of typhoid fever, however individuals who have been exposed to other forms of Salmonella may be reported as false positives and those with immunodeficiencies may be reported as false negatives. It can also be diagnosed with an ELISA test and DNA confirmation. Some people may carry typhus but have no symptoms; these people continually shed bacteria from their feces, infecting others. Response and Treatment Salmonellosis infections are not usually treated with antibiotics unless the case is severe. It is usually treated with oral rehydration therapy, which involves drinking water with added sugars and salts to treat dehydration caused by diarrhea. Immunocompromised patients requiring antibiotics are typically given fluoroquinolones, third-generation cephalosporins, and Ampicillin; however, antibiotic resistance is a concern. For example, the typhi serotype has seen numerous drug resistances throughout its history. Isolated cases of resistance to chloramphenicol (which was the drug of choice for treating typhoid fever before the 1970s) began appearing in Mexico in 1972, followed by reports in India, Vietnam, and Bangladesh. To combat resistance, treatment was changed to ampicillin and trimethoprim-sulfamethoxazole, but in 1975 a case of fans resistant to trimethoprim-sulfamethoxazole was reported in France. Nowadays, typhi has been defined as multidrug-resistant to the drugs ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole. Salmonella preventive health care includes thorough hand washing after handling raw eggs or contact with reservoir species. All surfaces where raw eggs or poultry have been prepared should be cleaned thoroughly. Vaccines for typhoid strains are available, primarily for people traveling to areas where typhoid fever is common. Programs around the world dedicated to identifying infected chicken populations have increased the likelihood of facing outbreaks in animals and animal products intended for human consumption (Gast, 2013). In Denmark, animal feed is treated to kill Salmonella strains, reducing the spread of salmonellosis. Contamination can also be reduced by improving slaughter methods to avoid cross-contamination, training employees who work with animals or food in hygiene care, and improving the storage and cleaning of animal products in factories, restaurants and homes. Epidemiology Salmonellosis is a worldwide disease. Globally, an estimated 93 million annual cases, with 155,000 deaths, are attributed to non-typhoid Salmonella strains.