How We Stop Contagious Illnesses from Spreading



ill person holding a thermometer in bed with a tissue

There are dozens of illnesses that, if you get them, you might end up on the phone with us! We help people access treatment and stop the spread of their illness (for illnesses that impact public health). Last week, we released the Communicable Illnesses Dashboard—an interactive report about these illnesses in Dane County and how common they are. 

Check Out the New Dashboard

What is a “reportable” illness? 

Reportable diseases are simply illnesses of public interest based on contagiousness, severity, or frequency. National guidance and state laws determine which diseases are considered reportable. Our new dashboard contains reportable illnesses only because those are the illnesses on which we receive data. There are many other illnesses out there aside from the ones we track—we just don’t have the numbers on them!

How do we respond to reportable illnesses? 

Laboratories and health care systems send us secure data, letting us know that someone has a reportable illness. We then work with the affected person to help prevent the spread of that disease by:

Investigating how they might have gotten sick

Giving advice for preventing future illness and stopping the spread to others

Offering connections to community resources

Contacting other people who might have been exposed so they can get tested or take preventative steps to stay healthy

What does our work look like?

The example below is not based on a real person. It is a general example of work we do.

A person began not feeling well with symptoms of stomach cramps, vomiting, and diarrhea. They went to the clinic and were diagnosed with Salmonella. Salmonella is a bacterial infection that often comes from eating raw or undercooked meat or eggs, or by drinking unpasteurized milk. People with Salmonella infection can then pass it to others via the fecal-oral route.

We contacted this person so we could check in on them and share additional informationWe also reviewed their symptoms, asked questions to help narrow down possible causes, and shared tips on how to prevent others from becoming ill.

Since Salmonella takes up to 7 days to show any signs of illness, we looked back at the full 7 days before their illness began. We learned that they may have gotten sick from an undercooked hamburger eaten at a backyard BBQ 3 days ago. Fortunately, the person reported that no one else from the BBQ or the person’s home had said they were ill. No Salmonella lab reports were received from this same exposure period to indicate that there may have been an outbreak from this BBQ.

To help prevent the spread, the person had stayed home from work at a daycare center. At home, they were washing their hands often and using a separate bathroom in their home. We advised the person and their employer that the safest time to return to work would be when they were symptom-free for 24 hours, and we sent them fact sheets to reference later. Thankfully, no one else got sick from this person's Salmonella infection.

Where can I learn more? 

Check out our new Communicable Illnesses Dashboard and our Disease Reporting webpage for more information!

This content is free for use with credit to Public Health Madison & Dane County .

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