WASHINGTON — Forget that old excuse of a dog ate my homework, this could be the new way for students to get out of class: Faking a positive COVID-19 test.
Viral videos circulating online claim that putting soda or juice on a testing swab can give kids a false positive.
It should go without saying: Don’t do this.
However, dozens of videos of faked positive results have popped up on TikTok. In each one, the creator gets a COVID-rapid test, dips it in soda, and out comes a fake positive result for the COVID test.
Can you fake a positive result on a COVID test by dipping in soda or juice?
- The COVID-19 test company LabCorp.
- Dr. Mark Lorch, a chemist and testing expert from the University of Hull in England.
Yes, soda or juice can cause a false positive in a rapid test, but not a PCR test.
WHAT WE FOUND:
According to LabCorp, you cannot get a false positive from soda or juice on a PCR test. PCR tests are the swabs that go to a lab and take several hours or days to get a result. Those are the tests that take a couple of days to get a result.
“Dropping soda or juice onto the testing swab for a PCR COVID-19 test will NOT give a false-positive result. COVID-19 PCR tests from LabCorp are extremely sensitive and 100% specific,” LabCorp said in a statement.
However, the COVID-19 rapid test is a different story.
“If you drop some Cola, or orange juice, or other actually any acidic beverages onto the lateral flow tests [rapid test], you get what looks like a positive result,” Dr. Lorch said.
According to Dr. Lorche, it’s not because the beverage has COVID in it. The acid in the liquid basically breaks the test, which makes the result look like a positive result.
“These tests, instead of your normal sample, the soft drinks are very gritty, quite acidic and they have a pH of about three to four,” Dr. Lorch explained. “Normally, these tests are designed to work about pH seven, not pH three.”
“You can spot a fake positive because if you let the device dry out a little bit and then add the buffer solution [it comes with the test] back to it, it washes away the fake positive line,” he said.
Which brings us to: How can parents and teachers prevent this from happening?
“It’s very, very simple,” he laughed “Watch the kids when they're doing it.”
TikTok has been taking down these videos as they appear, but each day new ones continue to pop up.