INDIANAPOLIS — Out of every 10 people who got tested for COVID-19 last month, seven of them had been tested at least once before.
Fewer people were getting tested for COVID-19 for the first time, with an even greater majority of testing shifting to retests in December.
The Indiana State Department of Health tracks both the number of unique individuals who have been tested for COVID-19 to date, 2.61 million as of last week, and the total number of tests administered at 5.59 million.
In those numbers, since the start of the pandemic about 53% of all tests have been retests on someone who has been tested at least once before.
But looking at daily numbers lately, as tracked by KPC Media Group, the retest rate has been accelerating.
In part, that makes sense — with 2.61 million people tested at least once, that means about 39% of all Indiana residents have been tested — since there are fewer people out there who have yet to be tested.
But December’s numbers represented a shift toward even more retesting than in previous months.
In both October and November, approximately 63% of tests were retests on someone who has been tested once before. But in December, that proportion increased to just shy of 70%.
Unlike earlier in the pandemic, Indiana has greatly expanded its testing capability, making it easier then ever for people to get tested, whether at free community sites, health department locations, doctors’ offices and even drive-throughs at local pharmacies.
Indiana saw its average number of tests administered daily climb from about 27,000 per day in October to 45,000 in November. Testing increased only slightly to about 45,700 per day in December, but the state has regularly seen days this month with more than 50,000 or even 60,000 tests processed.
There are several reasons why people may be retested for COVID-19.
A person who tested positive may seek a second test after they’ve recovered in order to be cleared to return to work. School students, teachers or staff may have been exposed multiple times during the fall semester, requiring them to get multiple tests.
Universities have run testing regimens not only for their athletic departments but also for general campus populations in an effort to keep surveillance on the virus’ activity. Nursing homes and health care providers may regularly test their employees to try to ensure they’re not bringing COVID-19 to work.
And, of course, people who may have been tested earlier in the year because they were exposed or sick may be exposed or get sick again later in the year and seek another test.
Despite case numbers shooting way up late in the year, most COVID-19 tests still come back negative.
The average positivity rate in December was about 12%, meaning 88% of people who go in for COVID testing receive a negative result and, therefore, leave the door open for them to get tested again in the future unless they’ve already contracted the virus and are therefore immune.
As Indiana has started vaccinations for COVID-19 this month, inoculating front-line health care workers, it’s possible testing numbers will begin to taper and decrease in 2021 as more and more people gain immunity through vaccination, thus eliminating the need for testing.