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Contact Tracing Metrics FAQ's

What are these metrics? How are they defined, measured and collected? How should I understand the metrics?

Case investigation and contact tracing are important strategies used to understand and limit the spread of COVID-19. Along with testing, social distancing, and vaccine (once available), these strategies help to protect the community against COVID-19.

The data on this website provide information about case investigation and contact tracing efforts by local health departments in Illinois and aggregated in total statewide. Here are the six initial metrics we are releasing starting (date TBD). [Insert link to data page].

How often will the data be updated? Is the state planning to release more data around contact tracing?

Metrics will be updated weekly, every Friday. Cumulative data from August 1, 2020 to the Saturday of the last full week will be available on this webpage.  Public data reporting is an evolving process. The IDPH is constantly striving to improve data quality and develop additional contact tracing and case investigation metrics that will help residents understand contact tracing efforts across the state. Information related to the current contact tracing workforce, timeliness of contact tracing efforts, contacts per case, … will be shared in the near future.

How many times does a local health department try to reach a case or a close contact?

Each local health department (LHD) has its own policy for how many attempts they make to reach a case or a close contact. In general, LHDs will try to place four calls to a working number before they determine that they cannot reach the person.  If a person cannot be reached by phone, some LHDs will send a letter by mail to provide individuals with quarantine and isolation guidance.

How do you ensure my data privacy is protected?

If you are diagnosed with COVID-19, a local health department worker may call you to check-in on your health, ask what resources you may need while you are isolating, discuss who you’ve been in contact with, and ask where you spent time while you may have been infectious and able to spread COVID-19 to others. During the contact tracing process, your name will not be revealed to those you may have exposed, even if they ask, unless you explicitly give permission.

Also, contact tracers will never ask about your immigration status, Social Security number or financial information. Any information you provide in contact tracing calls will not affect your health records.

The information we collect helps public health officials understand how the virus is spreading in the community and affecting members of the community. Data are anonymized and analyzed at an aggregate level – no individuals would be traced back with the data shared.

How can I help with the contact tracing efforts in the state / my community?

Answer the call. The team will ask you questions about when symptoms first developed, where and when you were exposed, and who you may have exposed to the virus.

Providing complete and accurate information (including sharing your close contacts) is crucial in helping health officials understand how the virus is spreading in the community. Your collaboration will help us fight this disease together, and stop the spread of COVID-19.

Isolation and quarantine give you time to recover from the disease, and limit further spread in the community. IDPH is working closely to support your social needs (connecting you to medical support and resources) during your period of isolation and quarantine. Lastly, if you’re interested in becoming a contact tracer and to contribute to the critical contact tracing work we’re doing, please fill out this interest form to let us know.

Why are some local health departments doing more contact tracing than others right now?

The first important factor is the volume of cases in each jurisdiction. In some areas, cases are growing faster than the jurisdictions are able to keep up with hiring. As the case numbers increase, it's been extremely difficult for them to keep up. There are some LHDs that had a solid infrastructure at the start of the pandemic and others had to set everything up in the midst of the response. Another major factor would be public participation in contact tracing, by having cases providing a valid phone number, answering the phone, responding truthfully to contact tracers, and sharing their close contacts with their valid phone numbers.