NEWS
18/08/2021 12:50 BST

Covid Test And Trace Has A Flaw. Here's What It Means For You

Even if you recover from Covid, you will continue testing positive for up to 90 days.

Scientists are aware people will continue to test positive for up to 90 days after their initial positive PCR test – even though that could mean they have to go back into self-isolation.

This positive result is likely to show up even though an individual is expected to have natural immunity during this period. Scientists do not think a positive test in this time frame indicates a reinfection.

The official government website states: “If someone has tested positive with a PCR test, they should not be tested using either PCR or rapid lateral flow tests for 90 days, unless they develop new symptoms during this time – in which case they should be retested immediately using PCR.

“This 90-day period is from the initial onset of symptoms or, if asymptomatic when tested, their positive test result.”

President of NYC Health and Hospitals Mitchell H. Katz warned that recovered patients may continue testing positive last November.

He said, “until clinical laboratories have the capability to test for the reproductive capacity of coronavirus” the reading of positive Covid tests among recovered patients “will remain challenging”.

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What if you have to take a PCR test?

Track and Trace recommend individuals who have tested positive not to take a test for 90 days from the day of their result.

However, this is not an option for everyone.

Before travelling from abroad back to England you must have proof of a negative Covid test even if you’re travelling from a country on the green list.

Travellers must take the test three days before “the service on which you will arrive in England departs”, according to the Gov.uk website.

Those who are fully vaccinated and do not need to self-isolate after being in contact with a positive case still need to do a free PCR test, too.

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Doctor in a protective suit taking a throat swab from a patient to test for possible coronavirus infection (a PCR test)

What happens if I do not self-isolate?

If your test comes back positive, Test and Trace will only be able to see that result rather than your Covid history – meaning you will have to self-isolate or you may be fined.

The NHS website states: “You could be fined if you do not self-isolate after getting a positive PCR test result.”

The team will contact you and may pass your details onto the local council if they are concerned you will not isolate.

OK, so what’s the best thing to do?

If you do test positive within 90 days of your self-isolation period – and do not have a high temperature or other Covid symptoms – you can call the Covid helpline, 119 for general advice.

Unfortunately you cannot overrule a positive Covid test and you will still have to self-isolate.

The Covid-pass app should recognise natural immunity

The NHS Covid Pass app, developed by the government for those aged 18 and over, can be used for those with proof of natural immunity as shown by a positive PCR test.

This natural immunity is expected to last 180 days from the date of the positive test and after a self-isolation period.

Use of the NHS Covid Pass is voluntary but can be a substitute in some cases instead of taking another PCR test, when entering some entertainment venues, for example.

Alex Walker via Getty Images
Antigen Lateral Flow Rapid Qualitative Test Kit

Why are lateral flow tests different?

In some cases, you may be able to use a lateral flow test rather than a PCR test.

Lateral flow tests are most effective at detecting the virus in those with high viral loads and are usually used for asymptomatic people.

The kits check if you are infectious with Covid and are conducted by the individual themselves at home – results are available 30 minutes after completing the test.

PCR tests look for the genetic material from the virus and are sent off to the lab before the individual can receive the result.

These are usually used for people with symptoms or who have been near a positive Covid case and can detect Covid very early into the illness.

As noted in the Medical Device Network, PCR tests are so sensitive they can potentially flag up a positive result upon detecting dead, deactivated virus cells in someone who has recovered from Covid.

Hindustan Times via Getty Images
A health worker administers a dose of Covid 19 vaccine to a beneficiary, on August 16, 2021 in Chandigarh, India

Recovered patients must also wait to get their vaccine

It’s important not to get either your first or your second dose of the vaccine when your body is still actively fighting Covid.

The NHS website explains: “It is recommended to delay any dose of Covid vaccine until at least four weeks after the onset of Covid symptoms or a Covid diagnosis.”

Scientists are not entirely sure how the virus impacts the immune system and how it could therefore impact the way you respond to the vaccine.