Can you test negative and still have Covid? What are the chances of a false positive or negative test result

If you have symptoms of Covid, but have tested negative you may be wondering if your results are correct.

But can you have Covid and test negative - and is it possible to get a false positive result?

Here’s what you need to know.

Are Covid tests still free?

Covid tests are no longer free for most people, but some can still get free rapid lateral flow tests from the NHS.

You can get tests if:

• you have a health condition which means you’re eligible for Covid-19 treatments
• you’re going into hospital
• you work in the NHS or in adult social care

If you still want to get tested and you’re not eligible for a free NHS test, you must pay for a Covid test yourself.

You can buy rapid lateral flow tests from some pharmacies and retailers, in person or online.

Can you have Covid and test negative?

The NHS website said: “A negative result means it’s likely you are not infectious.

“But a negative test is not a guarantee you do not have Covid-19 and there’s still a chance you may be infectious. You should follow advice on how to avoid catching and spreading the virus.”

The Health and Safety Executive (HSE) explained said that a negative PCR test result “does not mean that you’ve never had Covid-19”.

It’s possible that you had the virus, but that:

• your immune system cleared it by the time you were tested
• there was no virus present in the sample taken

The Centers for Disease Control and Prevention in the US (CDC) also said that if you have symptoms of Covid-19 you may have received a false negative test result and still might have the virus.

The CDC said you should contact your healthcare provider about your symptoms, especially if they worsen, about follow-up testing, and how long to isolate.

Can you get a false positive test result for Covid?

Research indicates that it’s unlikely that lateral flow tests (LFTs) will give out a false positive.

A Cochrane review from March 2021 assessed over 60 studies, all of which looked at the accuracy of various lateral flow tests, finding that the specificity of the tests was high.

This meant they had a strong ability to accurately diagnose those who were not infected with the virus.

Linda Geddes also wrote in a Gavi, the Vaccine Alliance post: “If you get a positive test result, you can be more confident that you really are infected.

“This is because the specificity of LFTs – their ability to accurately diagnose uninfected individuals – is higher, and therefore false positives are highly unlikely.”