The human nervous system

Emily classmate response #2

p. 549: Listeria Meningitis (Listeriosis) COLLAPSE Listeria meningitis, or Listeriosis is a bacterial infection of the brain that is typically caused by the ingestion of food which contains the bacteria Listeria monocytogenes. Foods most commonly contaminated by the bacteria are deli meats and unpasteurized milk. The virus mimics many flu-like symptoms in the first few days of infection. These symptoms include fever, fatigue, muscle aches and headaches. This is especially true in women who are pregnant. As the bacterial infection spreads to the nervous system, the symptoms begin to mimic those of other meningitis viruses including neck pain/stiffness, confusion, and severe headaches. The CDC considers events where 2 or more people have become sick with diagnosable foodborne illnesses originating from the same food product, a widespread foodborne outbreak. Since 2011, the CDC notes that there have been 15 widespread documented outbreaks. Of these outbreaks, deli meats and unpasterized or “raw” milk have counted for a substantial part of these. Each year an estimated 1,600 people are infected with the bacteria, while 260 die. This bacteria has adaptations that make it hard for the host cell immune system to fight the invading bacteria. The begin, Lasteria uses a mechanism called Phagocyosis to invade the body. This means the bacteria enters the body by adhering to the host cells and then breaking out of the phagosome and then into the cytoplasm. The host cell must have especially strong cellular immunity to fight this invading bacteria. This bacteria also has an adaptation where it invades the host by hiding in the anti-body meditated immune response. This makes it difficult for the host cell immune system to fight the bacteria. This is especially true in patients with compromised immune systems such as elderly patients, those who are pregnant (which make up 15% of cases), and patients with diseases like AIDS. Pregnant women are at especially high risk, but the bacteria can also spread across the placenta putting their unborn babies at risk as well. This can lead to neural defects, spontaneous abortion, or premature birth. These patients are all at risk for developing severe complications related to Lasteria meingitis, due to its properties and their compromised immune function. As cellular immunity becomes compromised, the bacteria begins to multiply and spread throughout the body without control.