Doctor explains how fizzy drinks and tap water could give false positive lateral flow results

An NHS doctor has revealed how tap water and fizzy drinks could lead to false positive lateral flow test results.  

Dr. Karan Raj, who is known for dispelling various health myths on TikTok, shared a video in response to a conspiracy theory that claimed pouring a fizzy drink on the Covid test – which resulted in a positive result – was evidence of the pandemic not being real.

In his video, Dr. Raj began by taking apart a lateral flow test kit to explain how exactly the kits work as well as the importance of the fluid that comes with the kit.

He explained: “This grey box and the portion just above it contains antibodies that are sensitive to the Covid-19 virus.

“If you use anything like soda, tap water and fizzy drinks then 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% saline solution – which provides a stable pH that will actually make the test work.”

So all you need to do is use the test as instructed and not pour any form of liquid or drink onto it… Who’d have thought it?

And if you’re still not convinced by Dr. Raj’s explanation, it was backed up by the American Society for Microbiology back in November, who confirmed that ‘a team of Canadian researchers has shown that rapid antigen tests for SARS-CoV-2 work only when manufacturer instructions are followed.’

This comes after school children across the UK were caught faking positive Covid tests by using fizzy drinks and orange juice to get time off school.

Back when the Covid isolation period was ten days long, crafty kids would apply various liquids to lateral flow tests to fake a ‘positive’ result to show to their parents and teachers.

However, they were rumbled after posting videos of their actions on TikTok, with Professor Andrea Sella of University College London saying it was not at all surprising.

She said: “If someone deliberately mucks up the protocol then of course you’ll get a duff result. But I would add that it’s not a ‘false positive’ in the true sense. Because false positives are ones that take place in spite of adherence to the protocol.”