Listeria monocytogenes
Introduction
Listeria monocytogenes, a motile, gram-positive rod, is an opportunistic food-borne pathogen capable of causing listeriosis in humans. Listeriosis includes manifestations of septicemia, meningitis, pneumonia, and encephalitis. L. monocytogenes is also implicated in miscarriages, stillbirth, and premature birth for pregnant women. L. monocytogenes is a tough bacterium resistant to freezing, drying, and heat; most strains have been shown to be pathogenic. It is hypothesized that 1-10% of humans are intestinal carriers of L. monocytogenes. Over 37 mammalian species, including wild and domestic animals, are capable of L. monocytogenes infection and transmission. Extensive environmental reservoirs for L.
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Pathogenic L. monocytogenes go through an intracellular life cycle involving early escape from the phagocytic vacuole, rapid intracytoplasmic multiplication, bacterially induced actin-based motility, and direct spread to neighboring cells, in which they reinitiate the cycle. The bacterium is first phagocytosed by these cells and secretes a pore-forming toxin called listeriolysin, which allows the bacterium to escape from the phagosome. All virulent strains of L. monocytogenes synthesize and secrete listeriolysin. Phospholipase A and B are other virulence factors that facilitate escape of L. monocytogenes from the phagosome. Once out of the phagosome L. monocytogenes is capable of rapid division in the cytoplasm, evading the immune response and moving throughout the cytoplasm from cell to cell. L. monocytogenes is well known for its ability to propel itself like a rocket through the cell cytoplasm. This is the result of the bacterium’s ability to polymerize actin filaments at its tail end. Actin is arranged in subunits to form microfilaments that are capable of directing cell movement. L. monocytogenes accomplishes cell motility through a virulence factor called ActA that takes advantage of normal actin polymerization going on in the cell. The ActA protein shares sequence homology with a protein called WASP that is found in virtually all eukaryotic cells. WASP is responsible for recognizing and
Esherichia coli also known as E. coli is a bacterium that lives in your gut. (1). it was founded by Theodore von Esherich in 1888. There are many people that can get the bacteria. Also there are thousands of strands of E.coli. Six E. coli O157 outbreaks were identified during 2007. Four of the outbreaks involved foodborne transmission. (Eshericha Coli). Six Minnesota cases and one Wisconsin case with the same or closely-related PFGE subtype of E. coli O157:H7, and an additional Minnesota case of Shiga-toxin producing E. coli that was not culture-confirmed, attended the Minnesota State Fair in August. All but one of the cases showed cattle or visited the cattle
Clostridium difficile is a particularly challenging and difficult infection to control. Because Clostridium difficile spores can live on dry surfaces for long periods of time, teaching must include the importance of cleaning surfaces and
However, everybody who has contact with the patient or the environment is entitled to relevant information that will enable them to reduce the risks of transmission to
The Maple leaf foods listeria outbreak resulted 22 deaths and a widespread recall of luncheon meat, Sandwiches and deli platters, more than 220 packages of produce and a 20$ million dollar settlement for the company as well as consumer confidence in the produce was jolted. The Outbreak was caused by two meat slicing machine’s that were contaminated with Listeriosis and not cleaned properly.
Once N. meningitidis has encountered a healthy host it uses its type IV pilus to protrude from the capsule and bind epithelial cells and erythrocytes within the mucosal surface. The pili also generate what is known as a twitch motility which allows the bacterium to pass the epithelial layer and invade the host.
. This bacteria can be contracted from both humans and animals because of the different toxins that this bacteria releases. This bacteria can be contracted from food and soil. Eating contaminated
Ampicillin is used to treat to Listeria monocytogenes meningitis. Within the age-group of this patient, the disease is only contracted by immunocompromised individuals, and there will usually be a history of ingestion of unpasteurized dairy products. Diagnosis is made by identifying motile gram-positive bacilli in a cold enrichment culture of the CSF. Other CSF findings include markedly elevated opening pressure (normal range being 70–180 mmH2O) up to 90,000 neutrophils/µL, decreased glucose (below 40 mg/dL), and increased proteins (above 40 mg/dL). An aminoglycoside may be added to the ampicillin treatment.
It is undeniable that the recent discovery of antibiotics and disinfectants in the past century is leading to the creation of increasingly dangerous antibiotic-resistant bacteria. Super bugs like Methicillin-resistant Staphylococcus have begun breaking out in hospital areas, killing more and more patients due to the lack of people following through with simple safety measures. In order to stop the creation and spread of antibiotic-resistant super bugs, proper precautions must be taken such as avoiding antibacterial cleaners, following through with instructions when taking prescriptions and maintaining adequate hand hygiene. Through adhering to basic safety rules, the creation and spread of super bugs can be minimized and all together
Antibiotics have played a major role in our society thanks to Sir Alexander Fleming's careful observations in 1928. Without it, many lives would be in danger due to infectious diseases. Antibiotics are chemical substances produced by various species of microorganisms and other living systems that are capable in small concentrations of inhibiting the growth of or killing bacteria and other microorganisms. These organisms can be bacteria, viruses, fungi, or animals called protozoa. A particular group of these agents is made up of drugs called antibiotics, from the Greek word anti ("against") and bios ("life").
According to acog.org (2014), the incidence of listerosis in pregnant women are higher than those who aren’t pregnant and are common in Hispanic women. In 2010, there were 0.27 reported cases of listerois per 100,000 people in the U.S., 8.9 being Hispanic pregnant women. It is usually diagnosed in the third trimester.
However, L. monocytogenes possesses a public health impact as a causative agent of listeriosis which considered one of the emerging food borne zoonoses (Dhama et al., 2013a) primarily contracted by ingestion of contaminated food products such as raw meat, dairy products, vegetables, and seafood (Allerberger and Wagner, 2010) and triggering primarily pregnant women, neonates, geriatric population, and those with weakened immune systems (Swaminathan and Gerner-Smidt,
Virulence Factors: The most important virulence factor of S. aureus is the specific surface proteins that allow the organism to attach to host proteins. The surface proteins of this bacterium allow it to attach to host proteins such as laminin and fibronectin, which form the extracellular matrix of epithelial and endothelial cells. S. aureus also produces a number of membrane damaging toxins that allow the organism to further invade and harm the host, of which the alpha- toxin is the most well studied and is the protein responsible for septic shock. The alpha- toxin is a protein that binds to a specific receptor in platelets and monocytes in humans, forming pores that eventually destroy the cell.
According the World Health Organization (WHO), antibiotic resistance is one of the world’s greatest health threats to date (Haddox, 2013). In the article, The Health Threat of Antibiotic Resistance, Gail Haddox (2013) discusses the danger antibiotic resistance poses in today’s society and strategies to prevent the expansion of antibiotic resistance. In Europe alone, an estimated 25,000 deaths have been attributed to multi-resistant infections (Haddox, 2013). Common infections are now harder to treat due to the increased resistance to antibiotics across the world, in fact some are becoming untreatable. Antibiotics should be treated like oil, a non-renewable resource (Haddox, 2013).
The bacterium evolved by loosing its genes converting it from a free-living microbe into a pathogen. It needs the host’s nutrients in order to survive. The bacterium latches itself onto the host epithelial cells by a 160 kDa type 1 pilli. The pilli, located on a specific organelle on the polar region of the
Macrobiotics is one of the many alternative diets that has gained popularity in the United States over the last couple decades. Michio Kushi introduced macrobiotics to New York City in the 1970's. Proponents of macrobiotics contend that it is not merely a diet, but a philosophy that, if properly observed, will ensure emotional, physical, spiritual and mental well-being. Good physical health is necessary before emotional, physical and spiritual wellness can be cultivated. See Foundation for the Macrobiotic Way