Virginia Department of Health
Plague: Guidance for Health Care Providers
Key Medical and Public Health Interventions After Identification of a Suspected Case
1. Clinical Manifestations
Plague is caused by the bacteria Yersinia pestis and has three forms: bubonic, pneumonic, and
septicemic. Pneumonic plague is communicable from person-to-person by respiratory droplets.
In rare circumstances, contact with exudates from buboes has been a source of plague
transmission. A small number of patients with bubonic or septicemic plague may develop
secondary pneumonic plague, which can then be spread by respiratory droplet.
A.
Bubonic Plague
Incubation Period – 2-8 days
Symptoms and signs – Patients develop sudden onset of fever, headache, weakness,
chills and swollen, extremely painful lymph nodes (buboes). Buboes generally develop
in the nodes that drain the site of the initial infection (typically in the groin, axilla or
cervical region). Nausea, vomiting, and diarrhea are common. Patients may develop
secondary septicemic plague or secondary pneumonic plague.
B.
Pneumonic Plague
Incubation period – typically 2-4 days (range 1 to 6 days)
Symptoms and signs – patients exhibit acute and often fulminant onset of high fever,
malaise, headache, myalgias, and cough with production of sputum that is initially
watery, before becoming bloody. Pneumonia rapidly progresses to dyspnea, stridor,
and cyanosis. Patients develop respiratory failure, shock, and ecchymosis. Nausea,
vomiting, diarrhea, and abdominal pain may be present.
C.
Septicemic Plague
Incubation Period – 1-7 days
Symptoms and signs – clinically resembles septicemia caused by other Gram-negative
bacteria. Patients are febrile and often have chills, headache, malaise, and gastrointestinal disturbances. May progress rapidly to septic shock, meningitis, and coma.
Patients may develop secondary pneumonic plague.
2. Identification and Isolation of Cases
Plague does not occur naturally in Virginia, but it does occur rarely in the western United States
and in other parts of the world. If any cases of plague were to be reported in Virginia, it would
be very important to determine recent travel history to high-risk areas (New Mexico, Arizona,
Nevada, Oregon, Colorado and California, and areas of Africa, Asia and South America).
If travel history does not implicate a possible source of exposure, bioterrorism may be suspected.
Early indications that plague may have been used as a biological weapon include: occurrence of
cases in locations not known to have enzootic infection; occurrence of cases in persons without
known risk factors; absence of prior rodent deaths; and sudden outbreak of illness in patients
presenting with severe pneumonia and sepsis.
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Use standard precautions for all types of plague. Additionally, for pneumonic plague, follow
droplet precautions until the patient has had 48 hours of appropriate antibiotics and shown
clinical improvement:
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Patients should be placed in a private room and persons entering the room should wear a
surgical mask, especially important when within six feet of the patient (N-95 mask not
required, but is also protective). Gloves, gown, and eye protection should also be used;
Patients should remain isolated during the first 48 hours. When private rooms are not
available, cohort symptomatic patients with similar symptoms and the same presumptive
diagnosis;
Limit movement and transport of patients and place a surgical mask on the patient when
transport is necessary; and
Practice concurrent disinfection of sputum and purulent discharges (also for bubonic plague).
If applicable, use an insecticide to rid patients and their clothing of fleas.
3. Handling Laboratory Specimens
Routine laboratory tests other than culture may be performed at Biosafety Level 2, but any
procedure that may generate an aerosol should be performed within a biosafety cabinet. Cultures
or manipulations of cultured material should be performed at Biosafety Level 3.
The Division of Consolidated Laboratory Services (DCLS) should be consulted about specimen
collection and processing. The DCLS Emergency Services Officer can be reached 24 hours a
day/7 days a week at 804-418-9923. Sample collection instructions are shown below.
Table 1. Sample Collection for Suspected Plague
Samples
Amount
Type of Plague
Instructions
Bronchial/tracheal
wash or induced
sputum
Lymph node aspirate
(bubo)
5-10 cc
Pneumonic
1-2 cc
Bubonic
Blood
10 cc
Septicemic
Cerebrospinal Fluid
5-10 cc
Serum
Acute and
convalescent 14
days apart
1 gram
Any type if
meningeal
symptoms
Septicemic or
Bubonic
Specimen of choice for pneumonic
plague. Place in sterile container. Store
and ship refrigerated.
Specimen of choice for bubonic plague.
Place in sterile container. Ship to lab
ASAP; if more than 2 hours, refrigerate.
Blood isolator tube or aerobic culture
bottle. Ship at room temperature.
Transport to lab within 16 hours.
Ship to lab ASAP; if more than 2 hours,
refrigerate.
Tissue: liver, spleen,
lung or bone marrow
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Any fatal case
Collect in red top or tiger top tube.
Remove serum and place in sterile tube,
then store frozen.
Place in sterile container; moisten with
sterile broth or saline. Ship to lab ASAP
at room temperature. If more than 2
hours, freeze and ship on dry ice.
Updated 07/27/2003
Isolates from the respiratory tract, blood or lymph node containing the major characteristics
below should be suspected as Y. pestis:
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Bipolar staining rod (Wright-Giemsa or Wayson) on direct smear
Pinpoint colony at 24 hours on sheep blood agar
Non-lactose fermenter, may not be visible on MacConkey agar or eosin
methylene blue at 24 hours
Oxidase and urease negative
Catalase positive
Growth often better at 28C
Additional laboratory guidance is available in the CDC publication Level A Laboratory
Procedures for Identification of Yersinia pestis, available at:
http://www.bt.cdc.gov/agent/plague/index.asp
4. Diagnostic Procedures
Table 2 lists the epidemiology, clinical signs, and laboratory studies for a diagnosis of
pneumonic plague infection.
Table 2. Diagnosis of Pneumonic Plague Infection*
Category
Indications of a
possible bioterrorism
event
Clinical
Manifestations
Laboratory Studies
Findings
Sudden appearance of several persons with fever, cough, shortness of breath,
hemoptysis and chest pain. Any case of pneumonic plague in the United States should
raise concern.
Gastrointestinal symptoms (e.g., nausea, vomiting, abdominal pain and diarrhea)
Patients have fulminant course and high mortality
Tachypnea, dyspnea, and cyanosis
Pneumonic consolidation on chest examination
Sepsis, shock and organ failure
Infrequent presence of cervical bubo
Purpuric skin lesions and necrotic digits only in advanced disease
Sputum, bronchial/tracheal wash or blood
Gram-negative bacilli with bipolar appearance (like a safety pin) on Wright, Giemsa,
or Wayson stain
Pulmonary infiltrates on chest radiograph
Additional tests are available at DCLS and CDC
*Excerpted from: Inglesby TV et al. Plague as a Biological Weapon: Medical and Public Health Management. JAMA.
2000;283(17):2281-2290.
5. Treatment and Prophylaxis
Supportive care combined with the rapid administration of parenteral antibiotics is the key to
successful management of plague. Pneumonic and septicemic plague are almost always fatal if
antibiotics are not started within 24 hours of onset of symptoms. Standard treatment should
continue for 10 days. Treatment regimens are shown in Table 3.
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Close contacts of pneumonic plague patients are individuals with contact at less than 6 feet when
the case is symptomatic and has not yet received 48 hours of antibiotic therapy. Close contacts
(including household and healthcare workers) should receive prophylaxis for seven days and
should be placed under medical surveillance for seven days. Contacts who develop a fever or
cough should seek prompt medical treatment, notifying the healthcare facility before arrival so
that proper infection control precautions can be implemented. Contacts who refuse prophylaxis
should be quarantined for 7 days after exposure. Prophylaxis regimens are shown in Table 3.
Table 3. Working Group Recommendations for Treatment and
Prophylaxis of Patients with Plague
Standard treatment should continue for 10 days and prophylaxis should continue for 7 days. Oral therapy should be
substituted when clinically appropriate.
Standard Treatment
Prophylaxis
Regimens in this column may also be used for treatment in
severe circumstances when standard IM or IV treatment is
impractical or unavailable.
Adults
Preferred Choices:
Preferred Choices:
Streptomycin, 1 g IM twice daily,* or
Doxycycline, 100 mg orally twice daily, or
Gentamicin, 5 mg/kg IM or IV once daily or 2 mg/kg
Ciprofloxacin, 500 mg orally twice daily
loading dose followed by 1.7 mg/kg IM or IV 3 times
daily
Alternative Choice:
Chloramphenicol, 25 mg/kg orally 4 times daily‡
Alternative Choices:
Doxycycline, 100 mg IV twice daily or 200 mg IV once
daily, or
Ciprofloxacin, 400 mg IV twice daily, or
Chloramphenicol, 25 mg/kg IV 4 times daily*‡
Children
Preferred Choices:
Preferred Choice:
Streptomycin, 15 mg/kg IM twice daily (maximum
Doxycycline, adult dosage if > 45 kg, if < 45 kg, then
daily dose 2 g), or
give 2.2 mg/kg orally twice daily, or
Gentamicin, 2.5 mg/kg IM or IV 3 times daily
Ciprofloxacin, 20 mg/kg orally twice daily, not to
exceed 1 g/day
Alternative Choices:
Doxycycline, adult dosage if > 45 kg, if <45kg give 2.2 Alternative Choice:
mg/kg IV twice daily (maximum 200 mg/d), or
Chloramphenicol, 25 mg/kg orally 4 times daily (not if
Ciprofloxacin, 15 mg/kg IV twice daily, not to exceed
child < 2yrs) ‡
1 g/day, or
Chloramphenicol, 25 mg/kg IV 4 times daily (not if
child < 2yrs) ‡
Treatment regimens shown are not necessarily approved by the FDA.
*Not recommended for pregnant women.

Other flouroquinolones can be substituted at doses appropriate for age.
‡
Higher concentrations (e.g., >25 ug/ml) are associated with increased risk of reversible bone marrow suppression. In addition, chloramphenicol can rarely
cause irreversible bone marrow suppression. Children younger than 2 years of age should not receive chloramphenicol.
6. Vaccine
U.S. licensed vaccine for plague was discontinued in 1999 and is no longer available.
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7. Decontamination
If a release of plague used as a biological weapon is suspected, instruct potentially exposed
individuals to: remove contaminated clothing and store in labeled, plastic bags; handle clothing
minimally to avoid agitation; and shower thoroughly with soap and water. Initiate post-exposure
prophylaxis when appropriate.
Hospital rooms of patients with plague should receive terminal cleaning consistent with standard
precautions, and clothing or linens contaminated with body fluids should be disinfected
according to hospital protocol.
Potentially contaminated material should be cleaned with a solution of 1 part household bleach to
9 parts water (0.5% sodium hypochlorite solution).
8. Postmortem Practices
If plague is suspected as a cause of death, the regional office of the state medical examiner
should be immediately notified. Consultation should occur regarding: whether an autopsy
should be conducted, parties responsible for conducting the autopsy, and proper personal
protective procedures to follow. Contact with and transport of body should be limited to trained
personnel.
9. Public Health Measures
A. Suspected cases of plague should be reported immediately to hospital
epidemiology/infection control, who in turn should notify laboratory personnel, other
medical care providers and public health.
B. Arrange for laboratory testing by consulting with DCLS at 804-418-9923 (24 hour/7
day).
C. Designated public health authority should begin an epidemiologic investigation
immediately.
a. Identify and treat close contacts of pneumonic plague patients with appropriate
antibiotic.
b. Put all contacts of cases of pneumonic plague under surveillance for illness for
seven days. Individuals who develop a fever or cough should seek prompt
medical treatment. Contacts who refuse prophylaxis should be placed under
quarantine for seven days.
c. If appropriate, flea and rodent control should be a part of the investigation and
follow-up.
Information excerpted from Inglesby TV; Dennis DT; Henderson DA, et al. Plague as a Biological Weapon:
Medical and Public Health Management. JAMA. 2000;283(17):2281-2290 and Chin, J. Control of
Communicable Diseases Manual, 17th edition; 2000; Plague; 381-387.
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