Part 1: Listeria monocytogenes Listeria monocytogenes is a bacterium that is originated in food and can cause the serious illness of Listeriosis. Listeriosis is a serious disease for humans; the overt form of the disease has a mortality rate greater than 25 percent1. This is a Gram-positive bacterium, and is mobile by means of flagella. Listeria monocytogenes can be found in nature in soil, water and animal feces, meaning it can be also be tracked to animals. In addition to humans, at least 42 species of wild and domestic mammals and 17 types of birds can harbor listeria monocytogenes as well as crustaceans, fish, oysters, ticks, and flies. It is also reportedly carried in the intestinal tract of 5-10% of the human population without any apparent symptoms of disease1. Listeria monocytogenes is able to resist the deleterious effects of freezing, drying, and heat remarkably well for a bacterium that does not form spores2. A human can consume this bacterium by eating a raw vegetable that grew in infected soil, or by eating improperly processed deli meats and unpasteurized milk products3. Healthy people rarely become ill from listeria monocytogenes infection. Possible complications due to the bacteria are blood infections and inflammation of the membranes and fluid surrounding the brain (meningitis). Other side effects that may develop are typical cold or flu-like symptoms. The real risk of infection is in the elderly, new born children, and pregnant women. During pregnancy, a listeria monocytogenes infection is likely to cause only mild signs and symptoms in the mother. The consequences for the baby, however, may be devastating. The baby may die unexpectedly before birth or experience a life-threatening infection within the first few days after birth3. The dangerous factor about the listeria monocytogenes is that the bacterium is able to grow in fresh food. The organisms
Cited: 1. van der Werf TS, van der Graaf WT, Tappero JW, Asiedu K. 1999 Sep 18. Mycobacterium ulcerans infection. PubMed.gov. 2. Poraels F, Johnson P, Meyers WM. 2001. Buruli Ulcer: Diagnosis of Mycobacterium ulcerans disease. WHO. 3-6 3. Johnson PDR, Stinear T, Small PLC, Pluschke G, Merritt RW, et al. (2005) Buruli Ulcer (M. ulcerans Infection): New Insights, New Hope for Disease Control. PLoS Med 2(4): e108. doi:10.1371/journal.pmed.0020108 4. http://www.news-medical.net/news/20120419/BuruliVac-project-getting-closer-to-a-vaccine.aspx