Guidance for Responding to a Plague Bioterrorism Event

Signs and symptoms of plague depend on how a patient was exposed to Yersinia pestis. Pneumonic plague is the most likely clinical manifestation following an intentional release of Y. pestis as a bioweapon. In addition to the usual systemic plague manifestations of fever, chills, aches, and fatigue, patients with pneumonic plague may experience rapidly advancing shortness of breath, chest pain, and cough, and sometimes will have bloody or frothy sputum. Patients with pneumonic plague pose a risk for person-to-person transmission.

Clinicians should be trained to recognize the signs and symptoms of plague. Ensure staff know your facility's plans for how to respond if plague is suspected; this includes notifying local and state health departments immediately and coordinating laboratory activities through the Laboratory Response Network (LRN).

Confer with state health departments to determine the appropriate specimens for diagnostic testing.

Person-to-person spread of pneumonic plague is via respiratory droplets, not fine aerosols. All confirmed, probable, and suspected pneumonic plague case-patients should be isolated under standard and respiratory droplet precautions during the first 48 hours of antimicrobial therapy and until clinical improvement occurs, or until plague has been ruled out. If large numbers of patients make individual isolation impossible, patients with pneumonic plague may be cohorted while undergoing antimicrobial therapy. After 48 hours of antimicrobial therapy, isolation and droplet precautions can be discontinued, however standard precautions should be continued.

Although isolation of a limited number of confirmed, probable, and suspected pneumonic plague cases may be initially accomplished in a hospital setting, local and state health authorities should be prepared to activate and utilize alternative facilities for larger outbreaks of plague.

Patients being transported, during any point in their course of illness, should wear surgical masks. After transporting a patient with suspected or confirmed plague, disinfect any equipment used (such as gurneys, wheelchairs, etc.) using standard disinfection procedures and handle linens with care.

More information on infection control

• Guidelines for Environmental Infection Control in Health-Care Facilities: Recommendations from CDC and the Healthcare Infection Control Practices Advisory Committee (HICPAC).

Read the full treatment recommendations for plague in MMWR.

Plague is a very serious illness but is treatable with commonly available antimicrobials. Early treatment of plague is essential. To reduce the chance of death, antimicrobials should be given within 24 hours of symptom onset. Recommended duration of treatment is 10 to 14 days. Treatment may extend beyond 14 days if a patient remains febrile or has other concerning symptoms.

In the event of a suspected bioterrorism attack, two different classes of antimicrobials should be administered to ill patients. It is possible that Y. pestis strains used in a bioterrorism attack will be engineered to be resistant to one or more classes of antimicrobials. Consequently, antimicrobial resistance testing should be obtained if an intentional release event is suspected. Note that both antimicrobial classes do not necessarily need to be first-line for treatment of plague, but ideally at least one class should be.

In addition to providing medical care to the patient, consider other ways to support the patient's general well-being. Patients in isolation may suffer from anxiety, depression, or report feeling stigmatized. They may also feel forgotten, as the need for personal protective equipment (PPE) reduces the frequency of interaction with clinical staff. Include in your facility's plans ways to allow for visitors, especially for pediatric patients. All visitors should wear appropriate PPE.

Healthcare and laboratory staff at potentially high risk for exposure during response activities should follow all standard and droplet precautions and use appropriate personal protective equipment (PPE). If appropriate precautions cannot be maintained due to surgical mask shortages, patient overcrowding, poor ventilation in hospital wards, or other crisis situations, certain groups such as emergency workers, healthcare providers, and environmental and public health investigators may consider taking pre-exposure antimicrobial prophylaxis [PDF – 1 page].

For staff who require pre-exposure prophylaxis, it is reasonable to discontinue use 48 hours after the last perceived exposure.

If plague is suspected, laboratory personnel should be notified when clinical specimens are sent so that they can take appropriate biosafety precautions.

Prior to an outbreak, train healthcare facility staff on:

• How to follow standard, contact, and droplet precautions in each staff member's line of work.
• The correct ways to don (put on) and doff (take off) PPE [PDF – 3 pages].

Prior to interacting with a patient with plague, all staff should don the appropriate PPE:

• Caregivers in close (<6 feet) contact with suspected or confirmed pneumonic plague patients are advised to follow droplet precautions in addition to standard precautions until a patient has been receiving antimicrobials for at least 48 hours.
• Consistent with standard precautions, healthcare providers should wear a mask and eye protection or face shield when performing procedures likely to generate sprays or splashes, such as bubo aspiration.
• Personnel participating in aerosol-generating procedures (e.g., intubation) should consider the use of a fit-tested N95 filtering facepiece respirator for additional protection.

Staff should remove all PPE, except for the surgical mask or N95 respirator (if worn), before leaving a patient's room. After removing gloves, the staff member should wash their hands with soap and water or use an alcohol-based hand sanitizer. Maintaining proper hand hygiene will help limit the spread of disease.

Following a bioterrorism attack, healthcare responders who have had close, sustained contact with patients sick with pneumonic plague while not wearing appropriate PPE should receive postexposure prophylaxis. Responders who require postexposure prophylaxis should be given antimicrobials for 7 days.

This two-part video series will help enable front-line healthcare providers to recognize, diagnose, and treat plague. These free online trainings serve as a valuable resource for providers who may encounter naturally occurring plague or plague caused by an intentional release.

Both wild and domestic animals can be infected with Yersinia pestis, either through bites of infected fleas, consumption of infected prey, or following inhalation of infectious droplets.

Pneumonic plague is the most likely clinical manifestation an animal would develop following intentional release of Y. pestis as a bioweapon. In addition to the usual systemic plague manifestations of fever and lethargy, animals with pneumonic plague may experience cough and sometimes bloody or frothy sputum. Characteristic symptoms of bubonic plague in animals include swollen, painful lymph nodes (buboes) in addition to systemic manifestations such as fever and lethargy.

Following an outbreak caused by the intentional release of Y. pestis, fleas may become infected after biting animals sick with plague. Fleas could then potentially transmit Y. pestis to additional animals through bites, resulting in zoonotic spread.

Veterinarians should be trained to recognize the signs and symptoms of plague in animals. Ensure staff know your facility's plans for how to respond if plague is suspected; this includes notifying local and state health departments immediately and coordinating laboratory activities through the Laboratory Response Network (LRN).

Confer with state health departments to determine appropriate specimens for diagnostic testing.

Plague is a serious illness but treatable with commonly available antimicrobials. Early recognition and treatment of plague is essential. To reduce the chance of death, antimicrobials should be given within 24 hours of first symptoms. In general, cats are more likely to develop life-threatening infections than dogs, but fatalities can occur in either group.

Veterinarians and other staff should use appropriate infection control measures and wear personal protective equipment (PPE) when examining animals or handling tissues from animals with suspected plague. Appropriate PPE may include the use of surgical masks, gowns, and gloves. Workers participating in aerosol-generating procedures, such as necropsy on a plague-suspect animal, should also use a fit-tested N95 respirator or the equivalent and protective eye equipment for additional protection. Any material used for examination should be disinfected.

Currently, there are no vaccines available for the prevention of plague in domestic animals.

Antimicrobial postexposure prophylaxis may be considered for veterinary staff accidentally exposed to infectious materials and those who had close (<6 feet) contact with infected animals.