This is because, unlike PCR tests, lateral flow tests cannot detect very low levels of coronavirus in a sample. This means the test may not give a positive result if you have only recently been infected; are in the incubation period; or if you have mostly recovered.

Are there different types of COVID-19 diagnostic tests?

There are 2 different types of COVID-19 diagnostic tests -- molecular tests and antigen tests. Molecular tests detect the virus that causes COVID-19, SARS-CoV-2. Antigen tests detect specific proteins made by the virus.

What are the chances of a false positive COVID-19 lateral flow test?

This is because the specificity of LFTs – their ability to accurately diagnose uninfected individuals – is higher, and therefore false positives are highly unlikely. In people who did not have COVID‐19, LFTs correctly ruled in infection in 99.5% of people with COVID-like symptoms, and 98.9% of those without them.