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Text Illness Monitoring (TIM)

Text Illness Monitoring (TIM)
Updated Nov. 5, 2020
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Text Illness Monitoring, or TIM, is a text messaging system that helps public health organizations monitor symptoms of enrolled participants. Public health organizations can use this system at no cost to monitor symptoms consistent with COVID-19.

About TIM            

Text Illness Monitoring (TIM) is a text messaging platform that helps monitor symptoms during an infectious disease outbreak. Public health officials have traditionally done symptom monitoring via telephone calls, which can be a time-consuming process requiring intensive resources. TIM allows for two-way short message service (SMS) text messaging to help public health organizations quickly identify enrolled participants reporting symptoms. TIM can be used to monitor an organization’s workforce or another specified population, such as contacts of an identified case.

TIM is available at no cost and, at this time, is primarily intended for public health organizations at the federal, state, tribal, local, and territorial levels to assist with COVID-19 response activities.

Using TIM for the COVID-19 Response

Since February 2020, multiple federal agencies have used TIM to monitor employees for COVID-19 symptoms. A number of state, tribal, local, and territorial public health authorities are also using TIM to monitor symptoms of enrolled participants in their jurisdictions.

Enrolled participants receive one or more text messages each day asking if they have symptoms consistent with COVID-19. Jurisdictions are immediately alerted when a participant responds YES or when a participant fails to respond to message reminders. A dashboard feature allows jurisdictions to identify and follow up with individuals who are reporting symptoms or those who have been unresponsive.

TIM Features

TIM includes many features to help monitor enrolled participants for symptoms of COVID-19. Organizations using TIM can:

  • Customize the duration of the monitoring period for an individual
  • Collect first and last names of participants within the platform
  • View a dashboard with summary information on the status of participants and symptom reporting
  • Remove/withdraw participants from monitoring
  • Designate when follow-up for YES responses or non-responses are in progress and complete
  • Keep track of who is working on a YES response or non-response
  • Edit text in messages to make them specific for the population being monitored
  • Use a Spanish workflow version
  • Allow participants to self-enroll by texting a keyword to the campaign phone number

Frequently Asked Questions


How do I get access to TIM?

State, tribal, local, and territorial public health authorities may request access to TIM by completing the form at the bottom of this page. The TIM support team will work with the requesting organization to provide access to TIM.

Can local public health jurisdictions use TIM?

Yes, local jurisdictions can use TIM for COVID-19 symptom monitoring.

Who will be able to access the information in TIM?

TIM allows access to information by two tiers. Public health administrators at the state, tribal, or territorial level (tier 1) will have access to all data within their jurisdiction, including local data. Jurisdictions assigned at the local level (tier 2) will only have access to the data for the jurisdiction to which they are assigned.

Dashboard and Notifications

What information is included in the dashboard?

The TIM system includes a dashboard with multiple visualizations, including detailed and summary information on monitored individuals and alerts that require attention (e.g., those who reply YES to a text indicating symptoms or those who have not responded to reminder texts). For alerts, jurisdictions can view the name and mobile phone number associated with the alert and the content of the text message.

How will I know if someone responds that they have symptoms?

TIM creates an alert when an enrolled participant:

  • Responds with a text that they have symptoms
  • Does not respond to the daily message after a reminder
  • Sends a text message to opt out

Administrators may log into TIM to view all alerts for participants. Each organization may also set up one email address to receive alert notifications via email.

Are there any reports available in TIM?

There are several reports and data extracts available in TIM.

  • Campaign Report (PDF document): Graphics on participant status, campaign status, and alerts at the time the report was generated
  • Participant Report (PDF document): History of all the text responses received and alerts over a specified time period for a participant
  • Participant download extract (CSV file): Detailed information on all enrolled participants
  • Responses download extract (CSV file): List of participant responses and time stamps over a specified time period

In addition to the reports and extracts, TIM includes a dashboard with summary information about participants, texting campaigns, and alerts as graphs and tables. The data in these graphs and tables can be exported as a CSV file.

Enrollment and Messaging

What messages will participants receive?

Organizations using TIM can personalize the text message workflow template available in the system based on their needs. Figure 1 below shows a sample of a text message template available in TIM. After the organization adds a participant’s mobile phone number to TIM, the participant will immediately receive a welcome message notifying them of their enrollment. Participants will receive a daily message asking whether they have symptoms consistent with COVID-19 and will be prompted to reply ‘Yes’ or ‘No.’ If a participant does not respond to the daily message, the TIM system will send a reminder. At the end of the monitoring period, participants will receive a final message informing them that they have completed monitoring and will be unenrolled from TIM.

TIM flowchart

Figure 1. TIM text message flow template sample

What information is needed to enroll individuals in TIM for monitoring?

The only information required to enroll a participant in TIM is a mobile phone number. Participants may also optionally enter their name.

Is there flexibility to change the template or the duration of monitoring?

Yes, there is flexibility to edit the text messages in the template. This can include the signs and symptoms listed in the daily question and other messages to meet the needs of the population being monitored. Users can change the monitoring period for the participants in their jurisdiction.


What data are stored in TIM for enrolled participants?

TIM has high privacy standards and includes only minimal personally identifiable information to support monitoring efforts. Data stored in TIM include the mobile phone number, participant’s name (if entered), number of days remaining in the monitoring period, and a history of text message responses (including content, date, and time). Administrators can also enter and edit notes for specific participant alerts.

How is the data in TIM secured?

TIM uses standard Security Development Lifecycle (SDL) principles, embedding security requirements into every phase of development. Standards defined by Amazon Web Services (AWS) are also in place to help protect customer data in accordance with personally identifiable information (PII) and HIPAA guidelines. The upgraded platform is hosted in AWS cloud centers. Connections established between users and the data centers are encrypted, and all public endpoints are secured using industry-standard Transport Layer Security (TLS). TLS effectively establishes a security-enhanced browser-to-server connection using HTTPS to help ensure data confidentiality and integrity between desktops and data centers. Unauthorized traffic is blocked to and within AWS datacenters. The infrastructure is constantly maintained, enhanced, and verified by AWS, and regular penetration testing is employed to continually validate the performance of security controls and processes.

Please complete this form if you represent an organization interested in using TIM for monitoring symptoms consistent with COVID-19.

We will reach out to you by email within 3 business days to discuss how TIM can help address your organization’s needs.