Francisella tularensis

Francisella tularensis is the contributing organism to the disease Tularemia.  F. tularensis is a gram negative, intracellular, coccobacillus that is highly infectious and may be easily transmitted to humans.

There are two subspecies of F. tularensis, F. tularensis subsp. tularensis and subsp. holarctica, both which cause human disease [1].  There are many means in which F. tularensis is transmitted to humans including working with infected animals, consumption of contaminated food or water, inhalation of contaminated aerosols, or by a tick bite or other such vector [2].  F. tularensis is carried by many mammals and therefore is transmitted by many vectors[3].  A few of these are the ticks Dermacentor reticulatus and Ixodes ricinus and mosquitoes such as Aedes, Anopheles and Culex species [3].  Most cases of Tularemia occur in the south central and west US.Each year in the US approximately 125 cases are reported to the CDC.  There are several types of Tularemia manifestations, the most common are ulceroglandular, glandular, oculoglandular, oropharyngeal, pneumonic, and typhoidal Tularemia[4, 5].  Until now, culture methods for detecting F. tularensis have often been used. The most widely used method of diagnosing infection by F. tularensis is serology.  Serology is successful in detection, but has poor sensitivity and accuracy in early infection.  The use of PCR methods, like those methods used by Spiro Stat technologies, are advantageous because they are rapid, specific and sensitive [5]. The most widely accepted form of treatment for Tularemia is the use of aminoglycosides such as streptomycin and gentamicin [3].  

References:

  1. Jason Farlow, et al.  Francisella tularensis in the United States.  Emerging Infectious Diseases.  CDC Dec. 2005.  11(12): 1835-1841. 
  2. Jeannine M. Petersen, et al.  Francisella tularensis: an arthropod-borne pathogen.  Vet. Res. 40(2): 7. 
  3. Jill Ellis, et al.  Tularemia.  Clin. Microbiol. Rev. Oct. 2002. 15(4): 631-646. 
  4. Tularemia. Division of Vector-Borne Infectious Diseases. CDC Jan. 2008.  http://www.cdc.gov/Tularemia/.
  5. Jeannine M. Petersen and Martin E. Schriefer.  Tularemia: Emergence/Re-Emergence.  Vet. Res. 2005.  36: 455-467.

Additional References:

  1. J. Erin Staples, et al.  Epidemiologic and Molecular Analysis of Human Tularemia, United States, 1964–2004.  Emerging Infectious Diseases.  CDC July 2006.  12(7): 1113-1118. 
  2. Kiersten J. Kugeler, et al.  Real-time PCR for Francisella tularensis Types A and B.  Emerging Infectious Diseases.  CDC Nov. 2006.  12(11): 1799-1801. 
  3. Damiana Chiavolini, et al.  Identification of Immunologic and Pathologic Parameters of Death versus Survival in Respiratory Tularemia.  Infect. Immun. Feb. 2008.  76(2): 486-496.
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Spiro Stat uses modern molecular diagnostic approaches that have been validated under stringent criteria. All laboratory testing is performed in our CAP accredited CLIA laboratory, Southwest Regional PCR.