Campylobacter Jejuni Is a Helical Shaped Non-Spore Research Paper
- Length: 8 pages
- Sources: 20
- Subject: Disease
- Type: Research Paper
- Paper: #78482727
Excerpt from Research Paper :
Campylobacter jejuni is a helical shaped, non-spore forming, curved, Gram-negative bacteria which is most often found in animal feces. This bacteria comes from the intestinal tracks of animals where is exists as a mixed surface-associated community, protected by an extra cellular material called a biofilm. The protection afforded to the bacteria by the biofilm makes it an extremely resilient bacteria. (Siringan, 2011) It was originally discovered by Theodor Escherich in 1886 and called "Vibrio," but in 1963 a new genus was created for this organism, called Campylobacter. C. jejuni is one of the "most important human enteropathogens among the campylobacter." (Nachamkin, 2008, p. 14) This bacterium is microaerophilic and "requires 3 to 5% oxygen and 2 to 10% carbon dioxide for optimal grown conditions." (Bad Bug Book) Prior to 1972, C. jejuni was believed to be primarily an animal pathogen causing enteritis and abortions in cattle and sheep, but it is now recognized as an important enteric pathogen in humans. Not only is it the most common cause of gastroenteritis and bacterial diarrheal illness, it has been linked to other diseases like Guillain-Barre syndrome, lymphomas, and Immunoproliferate Small Intestinal Disease (IPSID). (Lecuit, 2005) (Suarez, 2006)
C. jejuni is most commonly linked to poultry, sheep, cattle, birds, and even flies. It naturally occupies these animals digestive tracks and is often found in the resulting feces. From there, it is commonly transferred to humans through contaminated water, uncooked or under-cooked meat, and un-pasteurized milk. In the United States, it is estimated that there are 2.1 to 2.4 million cases of illness directly related to campylobacter. (Altekruse, 1999) The severity of illness ranges from loose stools to full dysentery and symptoms can include diarrhea, fever, abdominal cramping, and malaise.
Campylobacteriosis is an "infectious disease caused by eating or handling contaminated food or drinking contaminated beverages." ("Campylobacteriosis" NIAID) It is caused by bacteria called campylobacter, with Campylobacter jejuni, C. fetus, and C. coli being the types that most commonly cause illness in humans. In terms of food borne disease, C. jejuni is the leading cause of bacterial diarrheal illness in the United States. Between 5 and 14% of all diarrheal illness worldwide is caused by C. jejuni, which mainly effects children under 5 years old, as well as young adults between the ages of 15 and 30. ("Campylobacteriosis, NIAID)
One of the leading causes of the transmission of Campylobacter jejuni in the industrialized world comes from the farming of animals. Chickens, in particular are a major source of infection. It has been determined that there is "a definite correlation between human infection and consumption of chicken." (Moore, 1999) While it is possible to rear campylobacter-free poultry by using vaccines to rid the chickens of the bacteria, (Young, 2007) it was determined not to be economically feasible, and that reductions in the incidents of the disease should be attempted at the processing stage. It is at the processing stage that a solute may be added to the chicken that will hinder the growth of campylobacter jejuni, or the chicken can be exposed to drying operations which will reduce the amount of available water and thus disrupt the optimal growth environmental conditions. (Moore, 1999)
Pigs are another source of Campylobacter jejuni infections. Studies which have tested the feces of pigs have concluded that as many as 45% of all pigs are infected with C. jejuni at the time of slaughter. Because of the nature of the conditions under which pigs are raised, there are numerous opportunities for the colonization and cross contamination of campylobacter. On the other hand, red meat from cattle has been found not to be a major source of campylobacter infections, but the waste products of cattle did prove to be a source of infection.
Therefore, Campylobacter jejuni is a bacteria found in animal like poultry, sheep, pigs, and cattle. And while it can be found in ordinary birds and even puppies, the most common cause of campylobacterial infections is eating poultry and pork that has not been prepared, or cooked properly. C. jejuni bacteria can be found in cattle, but the meat of cattle has proven not to be a major source of infection, but the offal and waste products of cattle can be a possible source.
The symptoms of Campylobacteriosis, a disease that can be caused by C. jejuni, is often confused with the "flu." Symptoms include "headache, malaise, stomach cramps, muscle aches, and fever" which manifest themselves for up to 24 hours prior to the beginning of the intestinal symptoms. (Hunter, Chapter 5) After the first 24 hours, the symptoms of campylobacteriosis will change into those of classic gastroenteritis, including "nausea, vomiting, abdominal pain, and copious watery diarrhea." (Hunter, Chapter 5) It is common to have blood in the stool and bowel movements can occur as many as 8 to 10 times daily. Fever is reported as a symptom in more than 90% of cases, and it can go as high as 104 F. (Acheson, 2011) The infected person will endure these symptoms for approximately a week, but the stool will continue to contain the pathogen for several weeks. While the majority of infected patients will usually endure the symptoms for about a week, and then they usually subside, sometimes antibiotics like erythromycin are used to treat patients. (Salazar-Lindo, 1986)
Campylobacteriosis caused by C. jejuni is readily identified through a number of diagnostic tests. These include standard microbiological testing procedures like the Gram test, or even studying bacteria with a microscope. ("Campylobacter jejuni and Campylobacter coli," 2008) ) However, one of the most advanced and reliable test is known as a PCR test. PCR, or polymerase chain reaction, is a process by which DNA from a sample is mixed with all the components necessary to replicate a specific piece of DNA, and if large quantities of that DNA are detected, then the sample contains the genes that the researchers are looking for. In the case of C. jejuni, a sample of a patient's stool is usually filtered and purified, and the DNA found is then tested. It is then mixed with all the components necessary to replicate a specific piece of DNA that is specific to the C. jejuni bacteria. If the sample contains any C. jejuni DNA, then it will replicate itself a number of times through a heating and cooling process done in a PCR thermocycler machine. The resulting amplificate is made visible with s solution called "realtime" (SYBRGreen) which will turn the color green if there are amplified amounts of a particular DNA sequence. (NovaTec)
There is also another method for testing the results of a PCR thermocycler reaction, and that is gel electrophoresis. This process takes the results of the PCR process and uses electricity to move the resulting DNA through a gel. The addition of ethidium bromide will allow the DNA to fluoresce under a UV light indicating the presence or lack of the DNA that would indicate whether or not the C. jejuni bacteria was present in the sample. In effect, the PCR procedure tests for the presence of the bacteria C. jejuna's DNA is a sample of a patient's feces.
Most campylobacter infections are not fatal and do not lead to further complications. However, it has been estimated that approximately one out of every one thousand cases will prove fatal. And while the majority of cases do not result in any complications, there have been associations discovered by researchers between campylobacter jejuni infections and reactive arthritis, hemolytic uremic syndrome, septicemia, meningitis, recurrent colitis, acute cholecystitis, and Guillain-Barre syndrome. In other words, once a person becomes infected with campylobacter jejuni there is a small, but real, chance that they could develop other, more debilitating diseases.
Besides the initial gastroenteric illness of campylobacteriosis, the Campylobacter jejuni bacteria can be the cause of many other diseases, one of which is Guillain-Barre syndrome. This disorder has been linked by researchers to infections in humans caused by C. jejuni. (Yoshii, 2000) Guillain-Barre disorder is an autoimmune disorder, meaning that the body's immune system mistakenly attacks itself. In the case of Guillain-Barre disorder, the immune system mistakenly attacks part of the patient's own nervous system. ("Guillain-Barre Syndrome" NCBI, 2010) The exact correlation between C. jejuni infections and Guillain-Barre syndrome is not yet known, what is known is the syndrome may occur among either gender and at any age, it is most prevalent between the ages of 30 and 50.
This disease often follows a minor campylobacter infection, and the initial symptoms are usually gone before any symptoms of Guillain-Barre begin. It damages parts of the nerves, causing a range problems from simple tingling, and muscle weakness, to full paralysis. This disorder causes damage by effecting the nerve's covering, the myelin sheath, and is thus called demyelization. The most severe symptoms of Guillain-Barre can either take days to appear, or can appear very rapidly. "It may take only a few hours to reach the most severe symptoms." ("Guillain-Barre Syndrome" NCBI, 2010) But they appear, the symptoms can be debilitating and…