The numbers in Michigan were consistently low then suddenly 5,000 new
probable ones were added a few days ago:
Coronavirus in Michigan: State health officials announce 5,000 probable cases of COVID-19
For the first time, the Michigan Department of Health and Human Services is releasing data showing the number of probable COVID-19 cases and deaths. The probable cases total 4,928 while the probable deaths total 240.
Probable cases include individuals who never tested positive for the virus, but who were presumed to be infected due to their symptoms and past exposure. A probable death is defined as those whose death certificate listed COVID-19 as a cause of death or a significant condition contributing to death...
Coronavirus in Michigan: State health officials announce 5,000 probable cases of COVID-19 | News | theoaklandpress.com