Physicians who suspect tularemia should promptly collect appropriate specimens (see below) and alert the laboratory to the need for special diagnostic and safety procedures. Rapid diagnostic testing for tularemia is not widely available.
Growth of F. tularensis in culture is the definitive means of confirming the diagnosis of tularemia. Appropriate specimens include swabs or scrapings of skin lesions, lymph node aspirates or biopsies, pharyngeal swabs, sputum specimens, or gastric aspirates, depending on the form of illness. Paradoxically, blood cultures are often negative.
A presumptive diagnosis of tularemia may be made through testing of specimens using direct fluorescent antibody, immunohistochemical staining, or PCR.
The diagnosis of tularemia can also be established serologically by demonstrating a 4-fold change in specific antibody titers between acute and convalescent sera. Convalescent sera are best drawn at least 4 weeks after illness onset; hence this method may be useful for confirming the diagnosis but not for clinical management.
Treatment
Streptomycin is the drug of choice based on experience, efficacy and FDA approval. Gentamicin is considered an acceptable alternative, but some series have reported a lower primary success rate. Treatment with aminoglycosides should be continued for 10 days.
Tetracyclines may be a suitable alternative to aminoglycosides for patients who are less severely ill. Tetracyclines are static agents and should be given for at least 14 days to avoid relapse.
Ciprofloxacin and other fluoroquinolones are not FDA-approved for treatment of tularemia but have shown good efficacy in vitro, in animals, and in humans.
Infection control and environmental decontamination
Isolation is not recommended for tularemia patients, given the lack of person-to-person transmission. In hospitals, standard precautions are recommended.
Laboratory personnel should be alerted when tularemia is suspected. Standard diagnostic procedures with clinical materials can be performed in biosafety level 2 conditions. All work with suspect cultures of F. tularensis should be done in a biological safety cabinet. Manipulation of cultures and other procedures that might produce aerosols or droplets (e.g., grinding, centrifuging, vigorous shaking, animal studies) should be conducted under biosafety level 3 conditions.
Bodies of patients who die of tularemia should be handled using standard precautions. Autopsy procedures likely to produce aerosols or droplets should be avoided.
Clothing or linens contaminated with body fluids of patients with tularemia should be disinfected per standard hospital procedure.
Vaccination
Vaccination for tularemia is not generally available in the United states, nor is it useful in management of ill patients.
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