Listeria, Corynebacteria and Streptomyces.

• What type of bacteria are Firmicutes?

  Low GC gram-positive bacteria
• Are Firmicutes spore-forming or non-spore forming bacteria?

  Non-spore forming bacteria
• What are examples of lactic acid bacteria?

  • Streptococcus
  • Lactobacillus
  • Staphylococcus
  • Listeria
  • Mycoplasma
• Which bacteria are classified as spore-forming bacteria in Firmicutes?

  Clostridium and Bacillus
• What type of bacteria are Actinobacteria?

  High GC gram-positive bacteria
• What are examples of Actinobacteria?

  • Streptomyces
  • Nocardia
  • Corynebacteria
  • Mycobacteria
• What is Listeria monocytogenes known for?

  It is an important cause of disease in man and animals.
• How can Listeria monocytogenes be distinguished from Corynebacteria?

  By its tumbling motility at room temperature but not at 37°C.
• What type of bacteria is Listeria monocytogenes?

  Short, Gram positive, non-spore forming rod.
• What are the two types of listeriosis disease?

  Perinatal and Adult
• What are the characteristics of early onset listeriosis in perinatal cases?

  • Intrauterine infection
  • Sepsis
  • Death before birth
• What symptoms does listeriosis cause in immunocompetent adults?

  • Flu-like symptoms
  • Gastro upset
  • Resolution in a couple of weeks
• What antibiotics are used for the treatment of listeriosis?

  Penicillin and gentamicin
• What is the main reservoir of infection for Listeria monocytogenes?

  • Infected environment
  • Animals
  • Silage
  • Infected humans
• What is the normal route of infection for Listeria monocytogenes?

  The gastrointestinal route

  
• What food products are associated with listeria outbreaks?

  • Soft unpasteurized cheeses
  • Packaged meat (luncheon meat)
  • Fruits and vegetables
• How can listeria infection be avoided?

  • Pasteurization of dairy foodstuffs
  • Cooking of food
• What is a notable characteristic of Listeria monocytogenes regarding temperature?

  It is psychrotrophic and grows in the fridge.
• How many deaths and confirmed cases were reported in the 2011 listeria epidemic?

  33 deaths and 147 confirmed cases
• What led to the 2011 listeria outbreak in Colorado?

  • Cantaloupes were washed with potato cleaning devices
  • Failed to use chlorine spray to kill bacteria
• What was the impact of the listeria outbreak on public health?

  • Hospitalization of 147 people across 28 states
  • One woman suffered a miscarriage
• What is the mortality rate of diphtheria even with treatment?

  1. 10%
• What are the symptoms of diphtheria as described by the CDC?

  • Sore throat
  • Low-grade fever
  • Adherent membrane in the throat
• How is diphtheria spread?

  By droplets or contact.
• What are the effects of diphtheria toxin on the body?

  • Destruction of epithelium
  • Local inflammation
  • Systemic effects leading to lesions in kidney, heart, and nervous system
• What is the lethal dose of diphtheria toxin for humans?

  About 0.1 μg/kg
• What is used as a vaccine for diphtheria?

  Inactivated toxoid
• What is the Elek test used for?

  To test for the toxigenicity of diphtheria.
• What are the methods for diagnosing diphtheria?

  • Gram stain or methylene blue for beaded bugs
  • Aerobic growth on most media
  • Elek test for toxigenicity
• What antibiotics are used for treating diphtheria?

  Erythromycin is commonly used.
• What is the role of antitoxin in diphtheria treatment?

  It is used to neutralize the diphtheria toxin.