Data for the state of Missouri shows that when the tests are finished, the postivity rate drops. When the test drops, the percentage of positive tests increases
ST. LOUIS – The week of August 2, Missouri had 7,194 new cases of COVID-19.
The week of August 9, the state saw 7,945 weekly cases.
While the number of cases increased by less than 800 cases, the state’s positive rate dropped from 12.85% to 9.61
Because, during the week of August 2, 55,995 Missourians were tested. The following week, that number jumped to 82,701.
In fact, the week of August 16, cases dropped to 7,860 but the positivity rate for Missouri jumped to 11.35%.
The week of August 16, the number of Missourians who were tested dropped by nearly 13,000.
The positivity rate is important.
States are using it to determine which travelers should spend two weeks in quarantine upon arrival.
State and local governments use it as a factor in determining where and when to lift or tighten restrictions.
The positivity rate was one of the factors used by St. Louis County Executive Sam Page to restrict youth sports, which has since sparked multiple outrage and protests from players who want to play and their parents.
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But, at this point in the pandemic, how reliable is the positivity rate?
There is a negative relationship between the positivity rate and the test rates.
Data for the state of Missouri shows that when the tests are finished, the postivity rate drops. When the test drops, the percentage of positive tests increases.
Dr. Alex Garza, who leads the St. Louis Metropolitan Pandemic Task Force, said the testing capability in the St. Louis area is doing well. He said local facilities have the equipment and staff to meet testing needs, so the fluctuations in testing are coming from somewhere else.
“What we have seen is less demand for testing,” Garza said. “So, not many people sign up to go and get tested. Really, the best way to get tested is if you can test the entire population, but obviously we can’t do that, so we have to take it with a little bit of salt. “.
Because the postivity rate is highly dependent on people, on most people feeling sick or knowing they’ve been exposed to the test, the task force puts more emphasis on hospitalization data.
“It’s a good indicator of what’s happening in the community,” Garza said. “It doesn’t depend on how many tests are done. It depends on who is most affected.”
Hospitalizations in St. Louis are falling.
However, even when considering the positivity rate, it is important that the rate in St. Louis County is 5.8%, which is less than half the state rate and less than 6.62% of the positivity rate in the state. St Charles County, where high school athletes can play.
Dr Garza said that while data has been a factor in the decisions made, there has also been a lot of discussion about which activities are considered high-risk, including youth sports. While he said his team measures different factors some of which were used to create different rules and regulations, he said decision making during the pandemic was complicated and far from black and white.
“This is brand new,” Garza said. “We are learning. The more we learn, the better we can give advice.”