Synonym: Rabbit fever; Deer-fly fever; Francisella
tularensis infection
Category: Zoonoses
Agent Type: Bacteria
Acuity: Acute-Moderate
Latency/Incubation: 1 day to 2 weeks; usually 3-5 days
Initial Symptoms: Lymphadenopathy associated with a
skin ulcer (ulceroglandular type) or ulcers of the mouth/throat,
(oropharyngeal), or the eyes (oculoglandular). [CCDM]
Precautions: Standard; No isolation; Alert lab;
[JAMA]
Comments: Ulceroglandular tularemia usually presents as a painful skin ulcer followed by painful regional lymphadenopathy. (The anthrax ulcer is not painful.) The lymph nodes may suppurate. Lymphatic vessels may become inflamed and nodular. The differential diagnosis for ulceroglandular tularemia includes bubonic plague, chancroid, sporotrichosis, anthrax, and staphylococcal and streptococcal lymphadenitis. The differential diagnosis for glandular tularemia (lymphadenopathy without an ulcer) includes cat-scratch disease, tuberculosis, lymphogranuloma venereum, and bubonic plague. Hepatosplenomegaly may be found in patients with tularemia. A relative bradycardia was detected in 42% of cases in one series. Pneumonia may complicate any type of tularemia. It is common in typhoidal tularemia. Chest x-rays may show infiltrates, hilar lymphadenopathy, and pleural effusions. Mesenteric lymphadenitis and abdominal pain may follow ingestion of undercooked, infected game.
[ID, p. 62, 1446-51] Fever may be recurrent.
Pharyngeal tularemia is another syndrome that may be seen in outbreaks. A
pharyngeal membrane was reported in a few cases. Skin rashes have been
reported in up to 35% of cases and include erythema nodosum, erythema
multiforme, diffuse maculopapular rash, and urticaria. Sometimes found are
leukocytosis, thrombocytopenia, elevated transaminases, myoglobinuria, and
pyuria. Other complications of severe disease are DIC and hepatitis. [PPID,
p. 2927-37] "A nonspecific roseola-like rash may appear at any stage of
the disease." [Merck Manual, p. 1475] The WBC count is usually normal,
and the serum AST (SGOT) liver enzyme is commonly elevated. [Wallach, p.
933] EPIDEMIOLOGY: Reservoirs: ticks, some domestic animals, and wild
animals (rabbits, voles, muskrats, beavers). Other vectors are mosquitoes (Russian Federation
and Sweden) and deer flies. Drinking contaminated water is another source of
infection. [CCDM, p. 573-6] Rabbits, hares, beavers, muskrats, voles, and
sheep are the most common sources of infection in North America. Cats and primates have also transmitted infection. Dogs, horses, and swine
may become infected. Cattle are resistant. [Zoonoses, Vol. 1, p. 275-82]
Outbreaks have been reported after landscaping, mowing, and brush cutting.
Farmers may become ill after handling hay contaminated with excreta of
infected animals. The bacteria have been isolated from many species of
birds. [ID, p. 1448] See "Tularemia, typhoidal and pneumonic."
Diagnostic: Paired sera (4-fold rise) or a single titer
>160; FA test or PCR of exudates or aspirants; Culture is hazardous,
nonproductive, and done only in reference labs; [CCDM; Lexi-ID, p.
142]
Scope: N. America, Europe, former USSR, China, Japan
[CCDM]; About 125 cases/yr reported in USA with most in AR, MO, SD, and OK; [ID, p. 1447]
General Symptoms: fatigue; fever; fever, recurrent;
myalgia; sweating, excessive;
Other Findings: bradycardia; pharyngitis; abdominal
pain; hepatomegaly; liver function test, abnormal; leukocytosis;
lymphadenopathy; splenomegaly; thrombocytopenia; low back pain; delirium;
headache; conjunctivitis, acute; oculoglandular syndrome; cough;
lymphadenitis, acute; lymphangitis; papules or plaques; rash (exanthem);
ulcer of skin; urticaria; pyuria; diffuse infiltrates; hilar
lymphadenopathy; pleural effusions; segmental consolidation;
Complications: acute renal failure; ARDS; arthritis;
bleeding diathesis; endocarditis; erythema nodosum; meningitis;
osteomyelitis; pericarditis; pneumonia; sepsis; weight loss;
Syndromes: Entry Wound with Lymph Nodes; Adenopathy
Plus Fever;
Antimicrobic: Yes
Vaccine: Yes
Entry: Animal bite; Ingest; Inhale; Skin/Eye
Source: Excreta, Soil, Tissue
Vector: Biting Flies, Mosquitoes, Ticks
Reservoir: Birds, Cats, Cattle, Dogs, Horses, Monkeys,
Rabbits, Rodents, Swine, Wildlife
High-Risk Activities: Handle animal carcasses or
placentas; Handle dog or cat (bite or scratch); Handle infected rodents (not
bite); Raise farm dust (Francisella tularensis); Work in a medical or
research lab; Work or play in tick-infested area
