Look for syndromes in absence of cultures

Identifying the usual bioterror suspects

Health care facilities may be the initial sites of recognition and response to bioterrorism events, the Centers for Disease Control and Prevention warns. In a preparedness document written jointly with the Association for Professionals in Infection Control and Epidemiology, the CDC emphasizes that if a bioterrorism event is suspected, local emergency response systems should be activated.1 Notification should immediately include local infection control personnel and the health care facility administration. There also should be prompt communication with the local and state health departments, FBI field office, local police, CDC, and medical emergency services.

Act rapidly to prevent dissemination

Rapid response to a bioterrorism-related outbreak requires prompt identification of its onset. Because of the rapid progression to illness and potential for dissemination of some of the agents, it may not be practical to await diagnostic laboratory confirmation, the CDC warns. Instead, it will be necessary to initiate a response based on the recognition of high-risk syndromes. In addition to smallpox (see smallpox fact sheet, p. 33), typical combinations of clinical features of illness at presentation for other pathogens are summarized as follows:

Anthrax (Bacillus anthracis): Pulmonary variety would include nonspecific prodrome of flu-like symptoms following inhalation of infectious spores. Two to four days after initial symptoms, abrupt onset of respiratory failure, hemodynamic collapse, possibly accompanied by thoracic edema and a widened mediastinum on chest radiograph.

Botulism (Clostridium botulinum): Food borne variety will likely be accompanied by gastrointestinal symptoms. Inhalation and foodborne will likely share symptoms of: responsive patient with absence of fever; drooping eyelids; difficulty swallowing or speaking; blurred vision; descending paralysis of arms, respiratory muscles, legs; respiratory dysfunction.

Plague (Yersinia pestis): Clinical features of pneumonic variety include fever, cough, chest pain, hemoptysis, purulent or watery sputum with gram-negative rods on gram stain, radiographic evidence of bronchopneumonia.

General epidemiological suspicions: Features that should alert health care providers to the possibility of a bioterrorism-related outbreak include:

• a rapidly increasing disease incidence (e.g., within hours or days) in a normally healthy population;

• an epidemic curve that rises and falls during a short period of time;

• an unusual increase in the number of people seeking care, especially with fever, respiratory, or gastrointestinal complaints;

• an endemic disease rapidly emerging at an uncharacteristic time or in an unusual pattern;

• lower attack rates among people who had been indoors, especially in areas with filtered air or closed ventilation systems;

• clusters of patients arriving from a single locale;

• large numbers of rapidly fatal cases;

• any patient presenting with a disease that is relatively uncommon and has bioterrorism potential.

[Editor’s note: In addition to contacting local authorities for a suspected bioterrorist event, ICPs can call the 24-hour CDC Emergency Response Office at (770) 488-7100 or the CDC Hospital Infections Program at (404) 639-6413.]

Reference

1. Association for Professionals in Infection Control and Epidemiology Bioterrorism Task Force and Centers for Disease Control and Prevention Hospital Infections Program Bioterrorism Working Group. Bioterrorism Readiness Plan: A Template for Healthcare Facilities. 1999. http://www.cdc.gov/ncidod/hip/Bio/bio.htm.