Scientific evidence demonstrates that COVID-19 and the virus that causes it exist and are different from the flu

“We found no COVID-19 in any of the 1,500 [COVID-19-positive] samples” but influenza A and B; “what we're dealing with is just another flu strain like every year. COVID 19 does not exist and is fictitious”
Inadequate support: There is no publication or any other evidence that a laboratory analyzed 1,500 COVID-19-positive samples and found only flu viruses. Social media posts attributed this analysis to different researchers, many of them fictitious.
Inaccurate: Contrary to the posts’ claims, the virus that causes COVID-19 exists, is not a flu virus, and has been isolated multiple times. PCR tests for COVID-19 specifically detect the SARS-CoV-2 virus, and don’t give a positive result with flu or any other viruses.
Scientific evidence demonstrates that COVID-19 and the virus that causes it are real. Multiple independent laboratories isolated the virus and sequenced its whole genome, confirming that SARS-CoV-2 and not any other virus is what causes COVID-19.

FULL CLAIM: “We found no COVID-19 in any of the 1,500 [COVID-19-positive] samples” but influenza A and B; “what we're dealing with is just another flu strain like every year. COVID 19 does not exist and is fictitious”; “they've never really found the virus, all they've ever found was small pieces of RNA which were never identified as the virus anyway”


In little more than a year, the COVID-19 pandemic has caused 3,2 million deaths worldwide, 577,000 of them in the U.S. Still, false claims that the virus doesn’t exist and that the pandemic is a hoax continue circulating on social media. One example is this video posted on Instagram on 2 May 2021, which received more than 170,000 views and 8,200 interactions in two days.

The video featured an unidentified man who introduced himself as a clinical lab scientist with a PhD in virology and immunology. He claimed that several U.S. laboratories, including his own, analyzed 1,500 COVID-19-positive samples and couldn’t find the virus that causes COVID-19 in any of them but only flu viruses. The man presented this claim as proof that “COVID-19 does not exist and is fictitious”.

The man in the video is not a virologist; the claim was attributed before to different characters, most of them fictitious

Some social media users who shared the video identified the speaker as the virologist Derek Knauss. However, the man who appeared in the video is not Derek Knauss, nor a medical doctor or a scientist, but the influencer Patrick Gunnels. In fact, the name Derek Knauss is likely fictitious as there is no academic profile or scientific publication from a researcher with that name. Derek Knauss might also be an alias because the name figured as the author of several blog posts in a website labeled as a conspiracy-pseudoscience source by Media Bias/Fact Check.

Verbatim iterations of this claim from late 2020 and early 2021 attributed it to other apparently non-existent individuals, like Joe Rizzoli or Andrew Wye. In February 2021, Snopes traced the claim back to an anonymous post from 6 December 2020, stating, “it was a simple copy and paste. I am not a professional – merely a hillbilly”.

Other Facebook posts like this one falsely attributed the claim to Robert Oswald, a professor of Molecular Medicine at Cornell University in New York. Oswald, who has a doctorate in biochemistry, not in virology, issued a statement in his faculty profile page debunking this information:

“COVID-19 is real. Any Facebook post that suggests otherwise is a hoax and is not true. Wear a mask, practice social distancing, and get the vaccine when it becomes available.”

No evidence indicates that this analysis of 1,500 COVID-19-positive samples exists

The Instagram video claimed that seven U.S. laboratories examined 1,500 COVID-19 positive samples without finding any trace of the virus that causes COVID-19 but flu viruses instead. According to the video, they did this by “observation under a scanning electron microscope”. While electron microscopy is a suitable method for diagnosing viral infections[1], none of the posts provided any microscopy image or other data that supports this claim.

Earlier posts, like this Tweet from February 2021, attributed the analysis of the 1,500 samples to Dolores Cahill, a member of the group World Doctors Alliance, which repeatedly spread misinformation about the COVID-19 pandemic. In turn, Cahill claimed in a January 2021 video that someone else analyzed the 1,500 samples in October 2020 using genetic sequencing.

Public health authorities, including the WHO and the European Centre for Disease Prevention and Control, all told Reuters that they were unaware of such analysis. They also explained that finding influenza viruses in 1,500 samples in October 2020 would be an “extremely unlikely” event because of the low flu activity at that time due to COVID-19 restrictions. Furthermore, no scientific publication or other evidence indicates that any laboratory ever conducted these experiments. The multiple versions about when, where, and how the analysis was done raise further concerns about the veracity of this claim, making it unsupported, at best.

PCR tests for COVID-19 are specific and don’t detect flu viruses; the virus that causes COVID-19 exists and was isolated and sequenced multiple times

COVID-19 diagnosis depends on detecting the genetic material from the virus on the patient’s fluids by polymerase chain reaction (PCR) tests. As Health Feedback explained in previous reviews (here, here, and here), these tests specifically detect the virus that causes COVID-19 and don’t give positive results for other viruses.

Multiple laboratories across the world independently isolated and sequenced the virus that causes COVID-19, demonstrating that the virus does indeed exist and is not being confused with other viruses, like flu viruses[2-5].

Several studies also showed that the virus fulfils Koch’s postulates, as we explained in this previous review. These are a set of main criteria to establish whether a microorganism, such as viruses, bacteria, or fungi, is causing a particular disease. Contrary to what the video suggests, Koch’s postulates demonstrate that SARS-CoV-2 is indeed the cause of COVID-19[6-8].

Finally, the video claims that researchers only found “small bits of RNA which were only 37 to 40 base pairs long”. This claim is false and results from a complete misunderstanding of scientific methods. Different research teams sequenced the whole genome of the virus that causes COVID-19, consisting of almost 30,000 base pairs. Because this size is too big to sequence at once, the researchers independently amplify small overlapping fragments covering the whole viral genome. These fragments are later assembled, like a puzzle, based on their overlapping ends. The result is an accurate reconstruction of the entire genome of the virus.


It is false that the virus that causes COVID-19 is simply “another flu strain”. PCR tests specifically detect the virus that causes COVID-19, differentiating it from other viruses. There is no single evidence supporting the claim that COVID-19 patients are actually flu cases, as social media posts claimed. In contrast, multiple scientific studies isolated and sequenced the virus that causes COVID-19, demonstrating that the virus exists, is different from flu viruses, and is the cause of the disease.



Published on: 06 May 2021 | Editor:

Health Feedback is a non-partisan, non-profit organization dedicated to science education. Our reviews are crowdsourced directly from a community of scientists with relevant expertise. We strive to explain whether and why information is or is not consistent with the science and to help readers know which news to trust.
Please get in touch if you have any comment or think there is an important claim or article that would need to be reviewed.