DETROIT – The government noted several metrics that should be met for states to reopen during the coronavirus (COVID-19) pandemic. Where does Michigan stand? Should it be reopening soon?
Many states have surged ahead without meeting those measures.
UPDATE -- May 12, 2020: Michigan coronavirus cases up to 48,021; Death toll now at 4,674
The White House and the Centers for Disease Control and Prevention published the guidelines, which included a number of elements. Two critical elements were “a downward trajectory of documented cases within a 14-day period or downward trajectory of positive tests as a percent of total tests within a 14-day period.”
When you look at the graph of daily new cases, there are clearly several peaks and valleys occurring about every seven days since Michigan’s highest number of new cases on April 3.
Those bumps are the result of reduced testing on the weeks and delays in data reporting.
The problem is that the jagged pattern is hard to interpret if you’re trying to look for a consistent downward trend in new cases. That’s why experts look to something called a “seven-day moving average," which charts a point that represents the average number of new cases in the preceding seven days. It smooths out the graph, making trends easier to see.
When you overlay a seven-day moving average on Michigan’s graph of new cases, it’s clear that since around May 3, new cases have generally been on a downward path, and we might be near the 14-day period of decreasing new cases.
How are we doing when it comes to positive tests as a percent of total tests, and why is that important?
The graph is very busy, with red and green bars that represent the number of tests done on a given day and the red area at the bottom showing the number of positive tests.
Importantly, the graph shows that over time, Michigan is consistently doing much more testing. The graph with individual dots shows the percentage of tests that were positive on any given day, and when it goes down consistently, that means even though we are doing more tests every day, we aren’t finding more cases -- which is also a good sign.
Dr. Frank McGeorge said from seeing patients in the emergency room over the past several weeks, at least in Detroit, there has been a very consistent decrease in the number of new diagnoses of COVID-19. His observations match the state’s data.