What these numbers can tell us
The MI Symptoms Web Application is a symptom survey to be taken daily by Michigan residents and employees, for early detection of illnesses with COVID-like symptoms. This symptom survey may also help us better understand what influences the spread of the virus. We combine reports of COVID-like symptoms from MI Symptoms across the state into small geographic regions, so that we can see overall changes in an area over time.
We know that diagnostic testing for coronavirus cases will not capture all illnesses, especially since some people will have very mild symptoms and not get tested. In some places it has been estimated that only about 10% of the true number of cases are being captured by diagnostic testing. But people with mild symptoms can still spread the disease to others.
It is important to understand the number of people reporting symptoms consistent with COVID-19 so that we can:
- Have an early warning system for increased COVID-19 activity;
- Recognize trends in mild COVID-19-like illnesses for different regions across the state;
- and Better understand the full extent of community spread of COVID-19.
What these numbers don't tell us
These numbers are not laboratory confirmed cases of COVID-19. Other respiratory viruses can cause symptoms similar to those caused by COVID-19, especially when symptoms are mild.
These numbers also only represent users of MI Symptoms Web App. There are a number of reasons why users of this app may not reflect the overall population in the state of Michigan or in specific regions of the state. For example, some employers are using the MI Symptoms app to track illnesses among their employees, and so users may be more likely to be employed than the general public.
We also combine symptom reports over a 10-20 km area so that individual reports are not able to be identified, particularly in places with small numbers of reports.
For more information about the data collected by the MI Symptoms Web App and how users privacy is protected visit https://misymptomapp.state.mi.us/faq.