How tap water and fizzy juice can give a false positive Covid test according to NHS doctor

An NHS doctor took to the social media platform TikTok to explain how tap water and other soft drinks are showing up false positives for Covid-19 lateral flow test results.

Conspiracy theorists have used these findings as a justification that the pandemic, which began in the UK in March 2020, is a hoax or that there are less cases than what is being reported.Teesside Live reports that false positive results can be showed if the person carries out an antigen test incorrectly, which NHS medic Dr Karan Rangarajan detailed.

Dr Rangarajan, who is known as Dr Rajan on TikTok, recently took to the site to reveal why this happens after beingc challenged by a follower.In a clip, which has been viewed more than six million times, Dr Rangarajan, who is known for unravelling health myths on TikTok, could be seen splashing tap water on an antigen test before bringing up a positive result."First we need to look inside the lateral flow device," he said, before lifting the front casing off the test. "This grey box and the portion just above it contain antibodies that are sensitive to the Covid-19 virus."If you use things like soda, tap water and fizzy drinks, that's going to provide an altered pH, which will affect the function of the antibodies on the test line."That is why you need to use this buffer solution (consisting of 99.7 percent saline solution) which provides a stable pH that will actually make the test work."His explanation was also backed up by the American Society for Microbiology, back in November, confirming that "a team of Canadian researchers has shown that rapid antigen tests for SARS-CoV-2 work only when manufacturer instructions are followed." Don't miss the latest news from around Scotland and beyond - Sign up to