Implementing Communication Plans

Key points

  • During a Legionnaires’ disease outbreak public health officials may need to quickly communicate through multiple channels to different stakeholders.
  • Below are communication resources to help during a Legionnaires’ disease outbreak.

Communication toolkit

Protocols and guidance for communicating Legionnaires’ disease risks and mitigation information can vary across and within jurisdictions.

Legionnaires' disease risk communication toolkit‎

The Council for State and Territorial Epidemiologists (CSTE) offers a toolkit with comprehensive communications guidance for health departments, including setting- and scenario-specific modules.


Consider terminology. While people may perceive the terms "cluster" and "outbreak" differently, they have the same definition for Legionella. Health departments can use either term but should use the terms consistently.

Both terms describe two or more people with Legionnaires' disease exposed to Legionella

  • At the same place
  • At about the same time

The timeframe for defining an outbreak may vary depending circumstances. It's ultimately at the discretion of the public health jurisdiction performing the investigation.


Be prepared. Consider establishing a communications plan for outbreaks. It should include a strategy for when and how to provide updates to the general public and media.

Gauge level of public concern. Large numbers of cases often result in extensive media attention.

Make connections. Identify communications points of contact at the lead public health agency and facility, if applicable.

Coordinate early and often. Include key stakeholders at all levels (facility, local, state, and federal) to ensure clear and consistent messaging.

Getting the message out

Get engaged. Consider participating in community events, like town halls, to communicate information about the outbreak to the public and answer their questions.

Be consistent. Develop key messages. Suggested messages could include:

  • Estimate case counts rather than give an exact number
  • Explain the usual low attack rate for Legionnaires' disease outbreaks
  • Characterize transmission
  • Describe Legionnaires' disease symptoms
  • Give a call to action on when to see a healthcare provider

Stick to the facts. Provide information only and don't speculate. Explain what you know and don't know. Don't jump to conclusions regarding the outbreak source.

Strategies for special settings

Healthcare settings

Discuss with the facility staff how to notify employees, visitors, and patients in a proactive manner.

Travel accommodation settings

Discuss with building owners/managers how to notify guests and staff in a proactive manner.

Consider whether past guests should be notified about possible exposures that may've already occurred. They may have unrecognized or incubating infections.

Consider whether future guests should be notified of the potential for exposure prior to or upon arrival. This can give them an opportunity to find another accommodation if they're at increased risk.

Tips for writing notification letters

Convey what's known about the situation, who's at risk, and what's being done to protect against further illness. Consider addressing the following elements when drafting notification letters:


Who's the intended audience?

Exposure and case information

What's known about the case exposures? Does the available epidemiologic information point to a given setting or device as the source of exposure?

  • How many cases have common exposures?
  • What type of exposures are potentially implicated?
  • How tightly clustered in time were the cases?

What's known about the environment (i.e., the level of certainty that the implicated setting was the source)?

  • Has environmental sampling taken place?
  • If so, were any samples positive for Legionella?
  • Are there any clinical isolates?
  • Have the clinical and environmental isolates been characterized?
  • Does isolate comparison confirm the source?

Control measures

What measures have been taken so far or will be taken to prevent further cases?

How can those at risk protect themselves?

  • Who's at increased risk?
  • How do Legionella spread?
  • How's Legionnaires' disease treated?
  • What symptoms should people monitor for? How long?
  • Where can people find more information?

Be sure to include contact information for the appropriate public health jurisdiction.

The CSTE toolkit offers examples of notification letters.