Learning About Contact Tracing

What is contact tracing?

Contact tracing is a process that public health departments use to fight the spread of infectious diseases. These include COVID-19 (coronavirus), measles, and others.

A health department worker reaches out to a person who has tested positive for the disease. Then the worker calls other people who may have been exposed. Depending on the disease, the contact may have happened through close contact, by eating at the same place, or through sex. The contacts are told that they have been exposed. The worker can then guide the contacts on what to do next. This may include seeing a doctor, getting tested, or staying quarantined at home for a while.

Information about the person and their contacts is kept private. It's used only to help stop the spread of the disease. If you have any concerns about privacy, talk to the health department worker.

Why is it done?

Contact tracing helps reduce the risk of spreading disease among your friends, family, and community.

A person who tests positive for a disease can expose other people to it. Each of these people in turn can expose more people in an ever-widening circle. This raises the risk of more people getting sick. But a call from the health department can help both the person and their contacts take action so they don't spread the disease to others. Then the risk of illness and death in the community goes down.

How is it done?

Contact tracing usually starts with a phone call. A health department worker calls you to say that you've tested positive for a disease or that you've been in close contact with someone who has.

If you test positive for a disease

The caller will ask what symptoms, if any, you have. You may be asked about any health conditions that may put you at higher risk for serious illness. You'll be urged to follow local health department safety instructions. You may be asked to isolate.

The caller will ask where you've been recently. They'll ask for the names and phone numbers of anyone you've had close contact with. These people will also be contacted. Depending on how the disease spreads, the caller may contact any businesses or event venues you visited. Your name will not be given out unless you say it's okay.

If your contacts get early warning that they may have the disease, they can follow the safety instructions sooner. They may be less likely to pass the disease to other people.

If you are a close contact

If you were in close contact with someone who has the disease, the caller will urge you to follow local health department instructions. You may be asked to quarantine. Ask your doctor when it's safe to end your quarantine.

The caller will give you information about the disease and urge you to watch for any symptoms. You may be advised to get treatment. Follow the caller's instructions. You may be asked about other people you've come in contact with.