Francisella tularensis

Where Found

Tularemia ulcer on persons thumb

Naturally occurring tularemia infections have been reported from all states except Hawaii. Ticks that transmit tularemia to humans include the dog tick (Dermacentor variabilis), the wood tick (D. andersoni), and the lone star tick (Amblyomma americanum). Other transmission routes include deer fly bite, inhalation, ingestion, and through skin contact with infected animals.

Incubation Period

3–5 days (range 1–21 days)

Signs and Symptoms

  • Fever, chills
  • Headache
  • Malaise, fatigue
  • Anorexia
  • Myalgia
  • Chest discomfort, cough
  • Sore throat
  • Vomiting, diarrhea
  • Abdominal pain

(Ulcero) Glandular

  • Localized lymphadenopathy
  • Cutaneous ulcer at infection site (not always present)


  • Photophobia
  • Excessive lacrimation
  • Conjunctivitis
  • Preauricular, submandibular and cervical lymphadenopathy


  • Severe throat pain
  • Exudative pharyngitis or tonsillitis
  • Cervical, preparotid, and/or retropharyngeal lymphadenopathy


  • Non-productive cough
  • Substernal tightness
  • Pleuritic chest pain
  • Hilar adenopathy, infiltrate, or pleural effusion may be present on chest X-ray


  • Characterized by any combination of the general symptoms (without localizing symptoms of other syndromes)

NOTE: The clinical presentation of tularemia will depend on a number of factors, including the route of inoculation.

General Laboratory Findings

May be normal or elevated:

  • Leukocyte count and sedimentation rate
  • Thrombocytopenia
  • Hyponatremia
  • Elevated hepatic transaminases
  • Elevated creatine phosphokinase

May be present or not present:

  • Myoglobinuria
  • Sterile pyuria

Laboratory Diagnosis

  • Isolation of F. tularensis from a clinical specimen; or four-fold or greater change in serum antibody titer to F. tularensis antigen between acute and convalescent specimens.
  • Detection of F. tularensis in a clinical specimen by direct immunofluorescence assay (DFA) or polymerase chain reaction (PCR) assay; or single positive antibody titer to F. tularensis antigen.


These regimens may need to be adjusted depending on a person’s age, medical history, underlying health conditions, pregnancy status, or allergies. Consult an infectious disease specialist regarding individual patient treatment decisions.


Tularemia treatment regimen
Age Category Drug Dosage Maximum Duration (Days)
Adults Streptomycin 1 g IM twice daily 2 g per day Minimum 10
Gentamicin* 5 mg/kg IM or IV daily (with desired peak serum levels of at least 5 mcg/mL) Monitor serum drug levels Minimum 10
Ciprofloxacin* 400 mg IV or 500 mg PO twice daily N/A 10–14
Doxycycline 100 mg IV or PO twice daily N/A 14–21
Children Streptomycin 15 mg/kg IM twice daily 2 g per day Minimum 10
Gentamicin* 2.5 mg/kg IM or IV 3 times daily** Monitor serum drug levels and consult a pediatric infectious disease specialist Minimum 10
Ciprofloxacin* 15 mg/kg IV or PO twice daily 800 mg per day 10
* Not a U.S. FDA-approved use, but has been used successfully to treat patients with tularemia.
** Once-daily dosing could be considered in consultation with a pediatric infectious disease specialist and a pharmacist

NOTE: Gentamicin or streptomycin is preferred for treatment of severe tularemia. Doses of both streptomycin and gentamicin should be adjusted for renal insufficiency.
NOTE: Chloramphenicol may be added to streptomycin to treat meningitis.


Centers for Disease Control and Prevention. Tularemia—United States, 2001-2010. MMWR 62(47): 963–966.

Dennis D, Inglesby TV, Henderson DA, et al. Tularemia as a biological weapon: medical and public health management. JAMA 2001. 285(21): 2763–2773.

Feldman KA, Enscore RE, Lathrop SL, et al. An outbreak of primary pneumonic tularemia on Martha’s Vineyard. NEJM 2001; 345: 1601–1606.

Johansson A, Berglund L, Sjöstedt A, et al. Ciprofloxacin for treatment of tularemia. Clin Infect Dis 2001;33:267–8.

Penn RL. Francisella tularensis (Tularemia). In: Mandell GL, Bennett JE, Dolin R, editors. Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, PA:Elsevier/Saunders; 2015. p. 2590–2602.

Tarnvik A. WHO Guidelines on tularaemia pdf icon[PDF – 125 pages]external icon. Vol. WHO/CDS/EPR/2007.7. Geneva: World Health Organization, 2007.