CLAIM: A photo showing a COVID-19 test kit that includes swabs labeled “positive” and “negative” proves tests are manipulated to give a predetermined result.

AP’S ASSESSMENT: False. The photo does not prove the tests are being manipulated. The swabs labeled “positive control” and “negative control” are included in test kits for quality control purposes to make sure the tests work properly. Experts and test manufacturers say the use of such controls are standard for most rapid diagnostic tests.

THE FACTS: As the COVID-19 variant omicron generates a renewed wave of infections around the world, social media users are recirculating a photo from several months ago to falsely claim that COVID-19 test results are being planned in advance and that tests are unreliable.

One recent Instagram post showed a photo of a COVID-19 test kit manufactured by ACON Laboratories, which included test swab packages labeled “positive control swab,” and “negative control swab.” The post added the caption “Picture taken secretly by a nurse on shift. Name not mentioned for obvious reasons.”

The same photo has been circulating online since at least spring 2021, when users shared it with the sarcastic caption: “There’s no conspiracy involved at all! They aren’t trying to manipulate and control the test results in any way!”

However, the image is being misrepresented. The positive and negative control swabs are not used on patients, they are used to make sure the test kits work properly.

The swabs in the photo were part of an antigen rapid test first distributed in December 2020 by ACON Laboratories that was marketed for professional use, not as an at-home rapid test.

In this version of the test, a section of the instruction manual labeled “quality control” stated: “These control swabs should be used to ensure that the test cassette and that the test procedure is performed correctly.”

William Anderson, a t echnical support specialist with ACON Laboratories, confirmed this was the purpose of the swabs, and said it is “common practice” to include such control samples. He said the posts are misleading.

″Control samples are not intended to manipulate patient tests,” Anderson wrote in an email to The Associated Press.

ACON’s positive control swab is precoated with a SARS-CoV-2 recombinant antigen, according to the test kit instructions. Recombinant antigens are manufactured artificially in a lab. When the positive control swab is used on the kit, it is supposed to produce a positive result to demonstrate that the test is functioning correctly. Similarly, the negative swab should show a negative result.

The manual explained that the swabs could be used to test the product when a “new lot of tests are used and/or when a new operator performs the test” and at periodic intervals “as dictated by local requirements, and/or by the user’s Quality Control procedures.”

​​The controls are standard for COVID-19 diagnostic tests performed by laboratories because the sites typically perform a high volume of tests. Negative and positive controls are not usually included in home-use rapid antigen tests, according to a spokesperson for the U.S. Food and Drug Administration.

Loren Williams, a professor of chemistry and biochemistry at Georgia Tech, said the falsely captioned photos were “misrepresenting normal features” of these diagnostic tests.

He helped launch the university’s COVID-19 Test Kit Support Group in 2020. The group develops, produces and distributes some types of COVID-19 tests.

“For any good assay you need both positive and negative controls. And it is not just for the rapid tests, it is for any test,” Williams wrote in an email to the AP.

He added: “You cannot believe a negative result if your positive control is not positive. And a negative control ensures that your reagents are not contaminated. If you get a positive result in your negative control, then you generally have a contamination problem.”

A similar claim was made on Twitter about positive and negative swabs found in tests by Abbott Laboratories.

The company responded in a statement clarifying that: “We have a positive and negative control swab in each test kit to ensure the test is working properly. This is standard for most rapid diagnostic tests throughout the world.”

This story has been updated to include a response from ACON Laboratories.

This is part of AP’s effort to address widely shared misinformation, including work with outside companies and organizations to add factual context to misleading content that is circulating online. Learn more about fact-checking at AP.