Tag Archives: Francisella tularensis

CDC – Francisella tularensis

Tularemia is a disease of animals and humans caused by the bacterium . Rabbits, hares, and rodents are especially susceptible and often die in large numbers during outbreaks. Humans can become infected through several routes, including:

  • Tick and deer fly bites
  • Skin contact with infected animals
  • Ingestion of contaminated water
  • Laboratory exposure
  • Inhalation of contaminated dusts or aerosols
  • In addition, humans could be exposed as a result of bioterrorism.
  • Symptoms vary depending upon the route of infection. Although tularemia can be life-threatening, most infections can be treated successfully with antibiotics.

    Steps to prevent tularemia include:
    Use of insect repellent
    Wearing gloves when handling sick or dead animals
    Avoiding mowing over dead animals
    In the United States, naturally occurring infections have been reported from all states except Hawaii.


    Francisella tularensis bioweapon in waiting


    Francisella tularensis is a pathogenic species of Gram-negative bacteria and the causative agent of tularemia, the pneumonic form of which is often lethal without treatment. It is a fastidious, facultative intracellular bacterium which requires cysteine for growth. Due to its low infectious dose, ease of spread by aerosol, and high virulence, F. tularensis is classified as a Tier 1 Select Agent by the U.S. government, along with other potential agents of bioterrorism such as Yersinia pestis, Bacillus anthracis and Ebola virus

    Use as a biological weapon
    When the U.S. biological warfare program ended in 1969, F. tularensis was one of seven standardized biological weapons it had developed


    The F. tularensis is a highly contagious bacteria that can be spread from animals to humans, through vectors such as mosquitos and fleas, or from being breathed in from the air. The bacteria infects humans through skin, mucous membranes, lungs, and the gastrointestinal tract. It primarily infects macrophages of the host organism after it is ingested by phagocytosis. F. tularensis multiply inside the macrophage and later break out the macrophage and invades other cells. The major target organs are lymph nodes, lungs, liver, and kidneys. People infected with tularemia through inhalation also develop hemorrhagic inflammation of the airways early in the disease, and it might develop into bronchopneumonia. No proven vaccine has been created for tularemia, and the general treatment for the disease is antibiotics