Responding to a Tularemia Bioterrorism Event

Overview

Francisella tularensis, the cause of tularemia, is classified by the U.S. Federal Select Agent Program as a Tier 1 Select Agent. The Tier 1 classification indicates high potential for use in a bioterrorism attack based on a history of prior weaponization, stability in the environment, and an infectious dose as low as 10 organisms. Tularemia also occurs naturally throughout most of the United States, although it is not common.

Factors that suggest possible bioterrorism include:

• An unusual number or type of cases, such as several cases of pneumonic tularemia occurring in the same area or time period
• Tularemia cases in urban areas among people who lack exposure to arthropods or wildlife

If bioterrorism involving F. tularensis is suspected, public health, law enforcement, and CDC would work together with federal, state, and local partners to investigate and coordinate a response. CDC would provide support through the Emergency Operations Center.

Public health response steps

The recommendations below outline steps for public health practitioners to consider if bioterrorism involving F. tularensis is suspected.

Conduct patient interviews

Begin structured interviews with patients as soon as possible after human cases of tularemia have been identified. The immediate goals of the interviews are to:

• Confirm the cause of their illness
• Document onset dates and clinical features
• Identify the possible source(s) of the exposure

Define the scope of the event

Define the population likely exposed based on case interviews and suspected route of exposure. Management options for people who may have been exposed but are not yet ill include fever watch or antimicrobial prophylaxis. The immediate goals of this effort are to:

• Determine the location and number of people who were exposed
• Identify the best way to communicate with people who have been exposed
• Identify sites for possible environmental testing
• Determine if resources from the Strategic National Stockpile (SNS) may be needed

Communication

Accurate and timely communication with key audiences is essential during a tularemia bioterrorism event. CDC and other federal agencies will communicate about national-level efforts and assist state and local officials. State and local public health authorities will lead communication efforts within their jurisdictions about the response efforts that affect the local population.

Preparing to communicate effectively during a tularemia emergency is similar to preparing for any public health emergency. Prior emergency response work will be beneficial in informing communications.

• Ensure staff can confidently answer media and public questions on transmission, prevention, treatment, and prophylaxis. CDC's Crisis & Emergency Risk Communications trainings can help staff prepare.
• Make arrangements to establish a hotline on short notice.
• Identify media outlets to reach the public, including channels suited to people with functional, language, or cognitive needs.
• Confirm state and local rapid communication systems work. Upgrade systems as needed.
• Clearly identify the roles of state and local public relations offices.
• Create sample alerts for multiple formats, including broadcast, print, web, social media.
• Translate messages as needed for the community, and confirm accuracy and cultural appropriateness of the messages.

Resources and tools

• Tularemia Antimicrobial Treatment and Prophylaxis: CDC Recommendations for Naturally Acquired Infections and Bioterrorism Response — United States, 2025 | MMWR
• Managing occupational exposures to Francisella tularensis fact sheet
• The One CDC Data Platform (1CDP) can be used to track exposed people and collect information on the clinical course and outcomes of case-patients.
• The National Syndromic Surveillance Program (NSSP) can help identify patients with specific symptoms consistent with exposure.
• The Laboratory Response Network (LRN) can identify unusual features of clinical or environmental F. tularensis isolates, especially unusual antimicrobial resistance.
• The Health Alert Network (HAN) provides a rapid way to inform healthcare providers about tularemia, the potential for increased cases, how to report those cases to public health, and how to access treatment and prophylaxis if needed.