Quick Facts about Plague
- Plague is caused by Yersinia pestis, a gram-negative bacillus
- Plague is a zoonosis that affects primarily rodents
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- Endemic to Arizona, Colorado, New Mexico, and California
- Humans are "accidental hosts"
- Transmission occurs in one of five ways
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- Bites of infected fleas
- Human to human transmission of pneumonic plague by respiratory droplets
- Handling of infected animal carcasses
- Cat bites or scratches
- Deliberate aerosolization of bacteria
- Three plague syndromes are recognized
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- Bubonic
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- The most common naturally occurring form of the disease
- 2 to 8 days following inoculation symptoms include the abrupt onset of fevers chills, headache, and weakness
- Painful proximal lymphadenopathy develops, most commonly in the inguinal, axillary, or cervical areas. Lymph nodes become enlarged, matted, and associated with extensive, overlying edema (buboes)
- Gastrointestinal symptoms such as nausea, vomiting, and abdominal pain may occur
- Bacteremia may follow, resulting in sepsis and death
- Pneumonic
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- The most likely presentation of a bioterrorist attack
- Infection results from deliberate aerosolization of bacteria or contact with respiratory droplets from an infected person
- Symptoms develop 1 to 6 days following exposure
- Rapidly developing bronchopneumonia characterized by fever, cough, dyspnea, and serosanguineous sputum
- The time from respiratory exposure to death ranges from 2 to 6 days
- Suspicion of a deliberate attack should be raised by the rapid progression of a lethal pneumonia in a group of previously healthy people
- Septicemic
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- May arise secondary to bubonic plague or following a fleabite without the development of buboes
- Septicemia is associated with disseminated intravascular coagulation, necrosis of small blood vessels, purpuric skin lesions, and acral gangrene
- Death is the result of shock and multiple organ failure
- Diagnosis
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- Gram stain of the sputum or blood may reveal gram-negative bacilli or coccobacilli
- Under the best of circumstances, cultures of sputum or blood are positive in 24to 48 hours. Depending on method used, results typically may take from 72 hours to 6 days
- Rapid diagnostic tests, such as antigen detection, IgM enzyme immunoassay, immunostaining, and polymerase chain reaction are available only at selected state health departments, the CDC, and the military
- Survival depends upon presumptive treatment prior to microbiological confirmation of the diagnosis
- Treatment (based upon the interim recommendations of the Working Group on Civilian Biodefense, Johns Hopkins University Schools of Medicine)
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- Adults: Preferred choices
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- Streptomycin, 1 g IM BID
- Gentamicin, 5 mg/kg IM or IV once daily or 2 mg/kg loading dose followed by 1.7 mg/kg IM or IV TID
- Adults: Alternative choices
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- Doxycycline, 100 mg IV BID or 200 mg IV once daily
- Ciprofloxacin, 400 mg IV BID
- Chloramphenicol, 25 mg/kg IV QID
- Children: Preferred choices
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- Streptomycin, 15 mg/kg IM BID, maximum dose 2 g
- Gentamicin, 2.5 mg/kg IM or IV TID
- Children: Alternative choices
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- Doxycycline: If > 45 kg, give adult dose. If < 45 kg, give 2.2 mg/kg IV BID (maximum dose 200 mg/day)
- Ciprofloxacin, 15 mg/kg IV BID
- Chloramphenicol, 25 mg/kg IV QID
- Pregnant women: Preferred choice
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- Gentamicin, 5 mg/kg IM or IV once daily or 2 mg/kg loading dose followed by 1.7 mg/kg IM or IV TID
- Pregnant women: Alternative choice
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- Doxycycline, 100 mg IV BID or 200 mg IV once daily
- Ciprofloxacin, 400 mg IV BID
- Therapy should be continued for 10 days. Oral therapy should be substituted when patient's condition improves
- Post-exposure prophylaxis
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- Asymptomatic persons with household, hospital or other close contact (within 2 meters) with persons with untreated pneumonic plague
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- Adults: oral doxycycline, 100 mg BID x 7 days
- Children: if > 45 kg give adult oral doxycycline dosage. If < 45 kg, give oral doxycycline, 2.2 mg/kg BID x 7 days
- Pregnant women: oral doxycycline, 100 mg BID x 7 days
- Persons receiving post-exposure prophylaxis who develop fever or cough
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- Antibiotic treatment as described above for pneumonic plague
- Persons in a community experiencing a pneumonic plague outbreak who develop a fever > 38.5° C, or new cough, or infants with tachypnea
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- Antibiotic treatment as described above for pneumonic plague
- Infection Control
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- Isolate patients for the first 48 hours of antibiotic therapy and until clinical improvement occurs
- Transported patients should wear surgical masks
- Observe standard respiratory droplet precautions including gowns, gloves, and eye protection for close contacts
- Disinfect contaminated clothing and linens according to hospital protocol
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