Francisella tularensis: Possible Agent in Bioterrorism

Extract

Francisella tularensis, the causative agent of tularemia, is a highly infectious gram-negative coccobacillus. Due to its high infectivity it is of major concern to public health officials as a possible biological weapon. Although accidental exposure can occur through arthropod bites, handling infected animals, or breathing in aerosols, cases are usually isolated and contained. In the event of an intentional exposure such as in a bioterrorist attack, inhalation of aerosols can result in devastating consequences with much causality. Although a vaccine is available, sufficient quantities may not be readily accessible in an actual attack. Therefore, it is very important for both medical professionals and public health officials to be prepared to contain and control the situation should it actually occur.

There is an increasing threat that chemical and biological weapons will be used on civilian populations in an act of domestic or international terrorism. One of the identified diseases caused by an act of bioterrorism is tularemia, a systemic disease caused by Francisella tularensis. Human infections develop through a variety of mechanisms such as tick bites, direct contact with infected tissues, ingestion of contaminated water, food, or soil, and inhalation of aerosolized organism.^1-3

Francisella tularensis, is a small (0.2 μm in width by 0.2 to 0.7 μm in length), faintly staining, gram-negative pleomorphic coccobacillus. It is aerobic, non-motile, and requires cystine for growth.^4-7 Although it does not produce spores, F. tularensis is a very hardy organism.³ F. tularensis has a thin lipopolysaccharide-containing envelope that helps it survive for weeks at low…

ABBREVIATIONS: BSL = biosafety levels; CDC = Centers for Disease Control and Prevention; FDA = Food and Drug Administration; IM = intramuscular; IV = intravenous; NHI = Neisseria/Haemophilus identification; PCR = polymerase chain reaction.