Tool Of Pandemic Importance

Audrey Fraizer

Audrey Fraizer


For the first two months of the officially recognized COVID-19 pandemic, from March 1st to May 1st, 2020, dispatch agencies sharing data with the International Academies of Emergency Dispatch® (IAED) Data Center used the Emerging Infectious Disease Surveillance (EIDS) Tool on over 100,000 calls. To put this into context, these agencies handled a total of 404,664 calls during this period, which means that the EIDS Tool was used on approximately 1 out of every 4 calls over the first two months of the pandemic.

While the EIDS Tool was widely used during both the H1N1 influenza virus (swine flu) pandemic in 2009 and the West African Ebola virus outbreak in 2014, its largest deployment has been during the current COVID-19 pandemic. As the pandemic surged, so did use of the EIDS Tool.

EIDS Tool use skyrocketed during the pandemic. Dispatch agencies sharing data with the IAED Data Center called the EIDS Tool into play for 735,237 calls. Protocol 26: Sick Person (Specific Diagnosis) was the most often coded Chief Complaint (130,404 or 17.7%), followed by Protocol 6: Breathing Problems (105,003 or 14.3%), and Protocol 10: Chest Pain/Chest Discomfort (Non-Traumatic) (62,834 or 8.5%).1

Then the number of related calls dropped after a winter surge that claimed thousands of lives and overwhelmed intensive care units. While experts aren’t sure what caused the drop, the use of the EIDS Tool supports the dip. Between Feb. 21, 2021, and March 7, 2021, the total number of cases tallied in the Data Center in relation to the EIDS Tool was 33,129. Again, Protocols 26 and 6 were the most often coded Chief Complaints, at 18.72% and 16.96%, respectively.

Editor’s Note: The EIDS Tool is accessible from the Medical Priority Dispatch System (MPDS®), Fire Priority Dispatch System (FPDS®), Police Priority Dispatch System (PPDS®), and Emergency Communication Nurse System (ECNS).

The EIDS Tool

The EIDS Tool has two modes: Surveillance Mode and Trigger Mode. When used in Surveillance Mode, the EIDS Tool enables dispatch agencies to record findings to help monitor the spread of an infectious disease. Once an outbreak or epidemic is confirmed, the EIDS Tool is switched to Trigger Mode, where a positive answer to three or more questions activates a warning to alert the emergency dispatcher that there is a reasonable likelihood of an infectious disease so that responders on scene can be aware and take appropriate precautions.

Questions in the EIDS Tool cover symptoms, travel history, and patient contact history. The tool does not require the emergency dispatcher to ask a specific number or order of questions and leaves space for the medical director's previously approved additional questions and special instructions, according to policy.

Important EIDS Tool factors

  • The EIDS Tool does not provide for reduced responses and alternate dispositions–it is primarily used for surveillance and gathering key information for responders as determined by the system medical director.2
  • The EIDS Tool is not launched automatically off any Chief Complaint Protocols, but COVID-19 cases are most commonly present on Chief Complaint Protocols 6, 10, 13 (Diabetic Problems), and 26. However, the EIDS Tool can be launched manually from any point in the ProQA® call process (the IAED recommends, in general, to launch the EIDS Tool immediately after Final Coding is assigned, or within Protocol 26 to achieve the “C” suffix).3
  • Also, the EIDS Tool may be selected on other Chief Complaints when the caller offers information that would lead the emergency dispatcher to suspect a respiratory-type illness or at the direction of the local medical director.4

The MPDS Version 13.3 release (May 2020) added a function to send specific messages regarding the assessment findings to responders via Urgent CAD Message. Two new questions added to the MPDS, FPDS, PPDS, and ECNS in January 2021 record whether the patient tested positive for COVID-19 in the last 14 days or received a COVID-19 vaccination.

Dispatch screening capability

The EIDS Tool enables EMS authorities to implement an enhanced medical dispatch caller screening protocol for a specific disease outbreak for surveillance purposes only. Providing advance notice of potential widespread community transmission of infectious disease means more time to get out ahead of a potential outbreak, mobilize critical resources, prepare responders before they get on scene, and avoid being taken by surprise.

To examine and evaluate the effectiveness of the EIDS Tool, the IAED Research Team undertook a survey to gather input regarding users’ experiences and level of satisfaction.5 There were 136 unique respondents from both single and multiple-discipline users of the protocols. The researchers conducted both quantitative and qualitative reviews of the survey responses (the latter comprised of a thematic review and coding of free text responses).

Overall, more than 98% of the respondents reported that their agencies were using the EIDS Tool. Approximately 70% of respondents agreed that the EIDS Tool was easy to use, and more than half found that use of the EIDS Tool both enhanced the performance of their agencies (55%) and was helpful to EMS field personnel responding to calls amid the pandemic (52%). What makes these results particularly insightful is that many of the respondents (52%) indicated that their agency was using the EIDS Tool on all Chief Complaint Protocols (the currently advised use of the EIDS Tool is for Protocols 6, 10, 13, and 26).

A majority (61%) of survey respondents indicated that their medical director added agency-specific pre-arrival questions to the EIDS Tool. The three most common questions asked about patient symptoms, whether the patient had contact with an infected person, and whether the patient or relevant persons had been tested for COVID-19. Only a third (34%) of respondents indicated that their medical director added PAIs addressing where to meet responders or having the patient put on personal protective equipment. Most of the respondents perceived the questions regarding contact with an infected person and whether the patient/relevant persons had been tested for COVID-19 as very effective in identifying potential COVID-19 cases.

EIDS and infection detection

In 2003 the IAED created the Severe Respiratory Infection (SRI) Tool in response to the SARS outbreak—multiple cases were reported in Toronto, Ontario, Canada that year. Then in 2009, an electronic version of the tool was developed for ProQA dispatch software and deployed in multiple dispatch agencies during the 2009 H1N1 influenza virus (swine flu) pandemic. This tool was later modified in response to the West African Ebola virus outbreak in 2014 and became what is known today as the EIDS Tool. The diagnostic tool underwent further modifications to apply in the current COVID-19 pandemic.6

As described on the EIDS Tool Additional Information, coronaviruses are a large family of viruses that are known to cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). A novel coronavirus (CoV) is a new strain of coronavirus that has not been previously identified in humans. The 2019 Novel Coronavirus, or 2019-nCoV, is a new respiratory virus first identified in Wuhan, Hubei Province, China.

EIDS and Protocol 36

Protocol 36: Pandemic/Epidemic/Outbreak (Surveillance or Triage) provides for reduced response and alternate dispositions for potentially infected COVID-19 patients when deemed necessary by local authorities. It calls for bypassing several common Chief Complaints to get as many potential COVID-19 patients as possible in one “bucket.” Protocol 36 is used in anticipation of system stress, such as high call load, fewer available EMS resources, and hospital-patient overcapacity (i.e., part of your community’s medical surge plan).

Protocol 36 Key Questions are designed to distinguish probable COVID-19 patients from patients with other established medical conditions such as cardiac-caused chest pain and respiratory distress from other (non-COVID-19) causes. Protocol 36 shunts some cases to Protocol 10: Chest Pain/Chest Discomfort (Non-Traumatic) and Protocol 6: Breathing Problems when the patient condition is likely not due to COVID-19 (e.g., ≥ 35 yrs., chest pain, heart attack history). This ensures only likely COVID-19 patients get a reduced response or alternate disposition.

To take the associated CDE quiz, go to the IAED College at https://www.emergencydispatch.org/what-we-do/continuing-dispatch-education


  1. “Data Center Dashboards.” IAED Data Center.International Academies of Emergency Dispatch. 2020. https://www.emergencydispatch.org/the-science/data-center (accessed March 16, 2021).
  2. Scott G, Hotaling K, Olola C, Stout T. “Emerging Disease Surveillance and Triage using the MPDS ProQA software.” International Academies of Emergency Dispatch. 2020; March 7. https://www.firstwatch.net/wp-content/uploads/2020/03/Emerging-Disease-Surveillance-and-Triage-Using-ProQA-Tools.pdf (accessed March 16, 2021).
  3. See note 2.
  4. See note 2.
  5. AEDR Editorial Team. “EIDS Tool: The Early Surveillance System for Widespread Transmission of Infectious Disease.” International Academies of Emergency Dispatch. 2020; Oct. 17. https://aedrjournal.org/eids-tool-the-early-surveillance-system-for-widespread-transmission-of-infectious-disease/ (accessed March 7, 2021).
  6. See note 5.