It is true that the number of daily coronavirus cases have declined over the last two weeks, however, this observation also coincides with a decline in testing per capita in hotspots like Florida, as well as a rise in test positivity rates across 32 states, according to Business Insider.
Knowing this, it seems reasonable to assume the decrease in new cases may be the result of a shortage of testing supplies, as well as the public getting frustrated with having to wait long hours just to get tested and then waiting for days or weeks to get the results.
According to an Associated Press analysis, the number of tests done per day has fallen 3.6 percent over the past two weeks to 750,000, with the count falling in 22 states. This includes places like Alabama, Mississippi, Missouri and Iowa where the percentage of positive tests is high and continuing to climb, an indicator that the virus is still spreading uncontrolled.
Adding to the crisis has been a call for a cheaper, simpler test that would yield results in a matter of minutes and be easy enough for millions of Americans to test themselves. The big problem with this kind of test? It would be less accurate. “There’s a sense of desperation that we need to do something else,” said Dr. Ashish Jha, director of Harvard’s Global Health Institute.
When asked about introducing a cheaper, paper-based test, the government’s “testing czar,” Adm. Brett Giroir, warned that their accuracy could fall as low as 20 to 30 percent. “I don’t think that would do a service to the American public of having something that is wrong seven out of 10 times,” Giroir said last week. “I think that could be catastrophic.”
And most of us are mindful that it is essential that widespread testing is needed, along with contact-tracing, to contain the virus. We are approaching 5 million confirmed coronavirus illnesses in the U.S, and we are now very close to recording 158,000 deaths.So this leaves the question – Why do we have a decline in the number of cases of COVID-19?
“If cases are declining with the number of tests being performed, it is important to look at the percent positivity of tests,” Dr. Amesh Adalja, a senior scholar at the Johns Hopkins University Center for Health Security, told Business Insider. “If that statistic is increasing, that tells you that the outbreak is growing and the number of cases declining is a testing artifact.”
Think about it – a drop in the number of positive tests (or percent positivity) means we have enough tests available to detect the majority of coronavirus cases. However, when the positivity rate goes up, this means our testing capacity has fallen short.
“When you see percent positivity rising, that usually means that not every case is being captured by this system,” Adalja said in June. “All new cases should be something that’s already on the radar of public health officials — and that’s not probably the case where you have percent positivity rising.”
It’s all about the positivity rate
The positivity rate in the U.S. is now at 7.7 percent, down from 8.5 percent two weeks ago. This means it “has dipped only marginally,” Ian Shepherdson, chief economist at Pantheon Macroeconomics, wrote in an analysis published Monday.
Dr. Howard Koh, a professor at the Harvard TH Chan School of Public Health, previously told Business Insider that a positivity rate between 7% and 9% is “very disturbing.”
The World Health Organization (WHO) recommends that countries get their virus positivity rate down to 5.0 percent or even lower for a minimum of 14 days – or lock down to get an outbreak under control.
Currently in the United States, 14 states, including Arizona, Florida, and Texas, have positivity rates above 10 percent. Two states – Alabama and Mississippi — have positivity rates above 20 percent.
President Donald Trump has attributed the US’s extremely high case count to “big testing” efforts. “We have more cases because we have tested far more than any other country,” Trump tweeted on Saturday. He added: “If we tested less, there would be less cases.”
Actually, as of Monday, the US is administering 174 tests for every 100,000 people per day, putting it second in the world behind Hong Kong in testing per capita. In total, the US has administered more than 57 million coronavirus tests.
However, the country’s high percent positivity rate suggests the virus is still spreading rampantly. So do its hospitalization numbers. There are currently over 53,000 people in the hospital with COVID-19.
