There is a lot to know about this bacterium. There are over 2,500 different serotypes of Salmonella Enterica, for example serotype Typhimurium (Pg, 355) (Pommerville, 2011). Salmonella Enterica can cause many different infections like salmonellosis, typhoid fever, and gastroenteritis. Because of carelessness in personal hygiene, this kind of infection can turn into an outbreak very easily. (CDC, n. d. ) Salmonella is still a very common source of foodborne illness!
As of January 14th 2014 there was a reported outbreak of Salmonella Enterica Heidelberg involving Tyson mechanically separated chicken, which has (so far) infected 9 individuals (CDC, n. d. ). What is Salmonella Enterica, and how do we prevent it from spreading? Research mechanisms, virulence, prevention and treatment are all very important aspects of a bacterial infection and each topic will be thoroughly discussed in the text below. Methods for Studying Salmonella Microscopy. Microscopy methods of studying bacterial infections include using light and electron microscopes.
Light microscopy methods utilized include; conventional phase-contrast, fluorescence, and confocal microscopy. Electron microscopes create higher quality images; for example, they have been used for studying the structure of T3SS in salmonella. However, light microscopes are used more regularly than electron microscopes because they are more widely available. They are used to study the relations, and interactions, between cells in the body and bacteria. (Springer, 2007) Environmental testing. Clean and sanitized swabs or sponges are used to sample surfaces that may be contaminated with salmonella.
They are then put into an equally sanitized baggy that contains dey-engley broth. The sample is kept chilled until it is finally used for testing. When the swab or sponge is ready to be tested it is added to a jar with a lactose broth. Once mixed well, it is ready after about an hour. (FDA, 2007) Controlled Cultures. After getting the samples ready, it is time to test and see if what is there is in fact salmonella. Several different culturing methods are utilized when trying to identify salmonella infection.
Some of these test methods include, but are not limited to: Mixed cultures; which are mixed with MacConkey agar, hekotoen eneteric agar, or xylose lysine desoxycholate agar. Pure cultures; which include unease tests and optional unease tests. And lastly, serological polyvalent flagellar tests. (FDA, 2007) To give an example of how one of these test are done, I will explain the serological test procedure! The materials needed are glass slides, a bacteriology loop, a salmonella specimen, and sterile saline solution.
The glass slide should be divided into two sections with a marker, with a sample of saline in both halves. Using one of the bacteriology loops, the specimen is added into both halves. Then, undiluted antiserum is added to only one of the slides to create the “test” subject, the other being the “control. ” The slide is then “rocked” forward and back gently, and should accumulate clumping (or rather, agglutination) in around one minute. The test is positive if there is clumping in the “test” half of the slide, but is considered to be invalid if there is any clumping in the “control” half.
(Mount Sinai Hospital, 2000). Clinical Microbiology As defined by Salisbury University; Clinical microbiology is the study of microbes that can induce infection upon humans. Scientific methods like cultivation are utilized for solving medical anonymities. For example; if there is an outbreak of salmonella in a local town, scientists may perform cultures on several questionable foods. By testing all foods in question, they may be able to tell if a salmonella foodborne illness is the culprit, and what kind of food it was. (Salisbury, n.d. ).
Human Body & Salmonella Relations Salmonella Enterica serotype typhimurium is transferred when fecal matter is ingested into the body. The incubation period usually consists of about 5 to 21 days. During this period, the bacterial cells attack the small intestines causing; ulcers, blood in the stool, and abdominal pain. This can eventually cause the host to acquire a fever, potentially causing them to become lethargic or delirious. These symptoms can last anywhere for 3 to 4 weeks, and can become very sever if left untreated.
15% of people that go untreated pass away each year (Pg, 355-356). (Pommerville, 2011) Salmonella Virulence & Public Health Importance Salmonella Enterica serotype Typhimurium has an advantage when it comes to survival outside of a human body. It can stay alive for extensive amounts of time within water, different kinds of food, and sewage waste (Pg, 355). (Pommerville, 2011) It is important for the health department, as well as the general public, to know the causes of Salmonella type infections and how to prevent them.
Immunocompromised hosts, children, and elderly individuals are the most at risk for these infections. They should always make sure to practice practical personal hygiene; by washing their hands when necessary (CDC, n. d. ). Prevention and Treatment Strategies Prevention. Prevention of salmonella enterica is vital, because often times (like with any kind of infection) it is easier to prevent than to treat. Salmonella is found inside of the intestines of animals and humans. Salmonella infections are usually caused by food contamination.
Animal products like beef, chicken, eggs, and even milk are potential risk factors. However, even vegetables can become contaminated (CDC, n. d. ). To prevent an outbreak of salmonella poisoning, food handlers should always wash their hands after using the bathroom, or coming into contact with fecal matter by any other means (like changing a child’s diaper). They should also make sure that animal products are well-cooked and reach the appropriate temperature. It is also important to be sure not to cross-contaminate raw meat and ready-to-eat food like lettuce (CDC, n.d. ).
People whom are carriers of salmonella enterica may also be given an antibiotic known by the name of ciproflaxin, which assists with reducing the risk of passing it on to others (PHAC, n. d. ). Treatment. The treatment of a salmonella enterica poisoning depends on the outcome of the infection in the individual host. Treatment is based upon which symptoms and illnesses they happen to acquire from the infection, and what type of salmonella enterica they are infected with.
For example, people often come down with a case of gastroenteritis (also called “gastro” for short). The replacement of lost fluids and electrolytes would be the most effective way to treat gastro. Antibiotics may also be used, but are usually not necessary unless the individual is more at risk for more serious symptoms associated with gastro; children, the immunocompromised, and elderly individuals may be more at risk (PHAC, n. d. ). There are also vaccines available for certain types of salmonella enterica poisoning, for example typhoid fever has a vaccine.
Typhoid fever is caused by salmonella enterica serotype typhimurium. There is a vaccine that is taken orally, which is called Ty21a; which contains a weakened strain of S. typhi. Another (injectable) vaccine, called ViCPS, contains capsular polysaccharides from the S. typhi bacteria. These vaccines do become ineffective after a few years however, so booster shots are needed (Pg, 355-356). (Pommerville, 2011) In conclusion, individuals should know how to properly prevent contamination of salmonella enterica by utilizing proper hygiene mechanisms.
Research is extensive when it comes to bacteria, and while there are a few vaccines available for certain serotypes, it is likely that science will bring us more treatment options in the next few years. It would still be more beneficial for everyone to learn how to keep themselves safe from the beginning, rather than struggling to treat the illness itself. Resources (CDC) Centers for Disease Control and Prevention. (2014, January 24). Outbreak of salmonella heidelberg infections linked to tyson brand mechanically separated chicken at a correctional facility.
Retrieved from http://www.cdc. gov/salmonella/heidelberg-01-14/index. html (CDC) Centers for Disease Control and Prevention. (n. d. ). Salmonellosis. Retrieved from http://www. cdc. gov/nczved/divisions/dfbmd/diseases/salmonellosis/#treat (FDA) Food and Drug Administration. (2007, December). BAM: Salmonella [PDF]. Retrieved from http://www. fda. gov/downloads/Food/FoodScienceResearch/UCM309839. pdf Mount Sinai Hospital. (2000, March 27). Serological testing [PDF]. Retrieved from http://microbiology. mtsinai. on. ca/manual/ent/ent05_02. pdf (PHAC) Public Health Agency of Canada. (n. d. ).
Salmonella enterica spp. Retrieved from http://www. phac-aspc. gc. ca/lab-bio/res/psds-ftss/salmonella-ent-eng. php? Pommerville (2011). Alcamano’s Fundamentals of Microbiology (9th ed. ). Jones & Bartlett. Sudberry, MA Salisbury. (n. d. ). Clinical Microbiology. Retrieved from https://www. salisbury. edu/healthsci/medtech/MTContentAreas/clinmicr. html Springer. (2007, August 22). Salmonella: Methods and protocols (H. Schatten & A. Einsenstark, Ed. ). Retrieved from http://books. google. com/books? id=gpiH7FANUwsC&dq=microscope+used+for+salmonella&source=gbs_navlinks_s.