The Healthy Return Approach

• There are two main types of test in use. The first is a reverse-transcription polymerase chain reaction test, or RT-PCR. This is the most common diagnostic test used to identify people currently infected with SARS-CoV-2. It works by detecting viral RNA in a person’s cells – most often collected from their nose.
• The second test being used is called a serological or antibody test. This test looks at a person’s blood to see if they’ve produced antibodies for the coronavirus. If a test finds these antibodies, it means a person was infected and made antibodies in response, which implies some level of immunity to being re-infected.

A PCR test looks for the presence of the RNA of the virus itself. This test involves extracting RNA (ribonucleic acid) from nose or throat swab samples and converting it into DNA. This is then replicated many millions of times in a laboratory so that a significant quantity of DNA can be detected by a PCR machine. Detection indicates that the virus is present in the patient’s system. This means that it will pick up the presence of the actual virus in the nose and throat. It is very accurate and will be able to confirm whether anyone with symptoms is actively infected with the virus. It will also pick up whether the virus in present for people who have been exposed but are not showing any symptoms as yet. This is a more expensive test as it requires more technical expertise. It will also be able to confirm whether someone has the virus in their nose and throat for the 14 days or so before they show any symptoms.

• This is the same test being used by PHE and is 99.9% accurate with the correct sample taking technique. It is the most accurate test available.
• The current evidence shows a mean incubation period before symptoms emerge of 5 days. This test has a sensitivity of under 100 copies of viral RNA and shows 100% homology to the Wuhan strain of the virus. This means that, provided there are more than 100 copies of viral RNA in the sample, the test will successfully detect it.
• Taking a swab from your nose and the back of your throat is a relatively straightforward process but proper care needs to be taken when doing it to ensure the test has the best chance of being accurate.

• Antibodies are part of our immune system. When we get an infection, such as COVID-19, antibodies are produced, which attach to the virus and activate the rest of the immune system to attack and clear the virus.
• IgM is the first to be produced and is a general antibody that can bind to many different types of pathogen. The presence of IgM is an indicator of early infection.
• IgG is a more specialised antibody that specifically binds to the SARS-CoV-2 virus. The presence of IgG is an indicator of later stage infection.
• A suitable antibody test for Covid-19 would reveal the presence (or not) of these two antibodies.

It is widely accepted that the best test for an early infection is combining the antibody test and the PCR swab taken from the patient*.

As reminder, Immunoglobulin M (IgM) is the first antibody the body makes when it fights a new infection. It usually appears seven days post-infection and peaks at 21 days. Immunoglobulin G (IgG) takes approximately 14 days to appear but then remains, providing immunity.

We can see from the graph that there is an initial period lasting several days when you might have the coronavirus, and may have already developed symptoms – this is the blue line – but you would not test positive for the IgM antibody. During this time, a PCR test should detect  the presence of the virus.

Therefore, if the antibody test is being used to diagnose a current infection as well as to detect the presence of antibodies, it must be used with a PCR test.

* https://institute.global/tony-blair/path-mass-testing

• If your IgG test is positive it means you have had Covid-19 exposure sufficiently to make an antibody response to the virus. There is currently no scientific evidence confirming if the presence of antibodies correlates to immunity or how long the antibodies will last for.
• If your IgG test is negative, it means you have not been exposed sufficiently to make an antibody response or there has not been sufficient time for the body to make an antibody response. There is also a possibility that your body made an antibody response which has not been sustained and is therefore not detectable when it was tested for. Some patients with other underlying health conditions specifically related to their immune system may also not be able to mount a detectable or sustainable immune response and therefore may test negative. Please note that some people may not develop IgG antibodies even after proven infection with Covid-19 and will therefore test negative.
• As a responsible CQC registered provider, our medical partner GPDQ abide by CQC guidance on this issue.
• We would like to be clear all testing and the results obtained are for guidance only and one must not assume having antibodies means having immunity nor does it mean that reintegration into society is acceptable without following government safe guidelines on social distancing and acceptable practices around reintegration.

Please see guidance as below:

https://www.cqc.org.uk/guidance-providers/independent-healthcare/regulating-coronavirus-covid-19-antibody-testing

GPDQ is the UK’s leading multichannel employer healthcare service. Commissioned by the NHS in London and Birmingham to provide COVID-19 support for 1 million patients, employers  currently working with GPDQ have seen a 40% reduction in absenteeism for employers. GPDQ are now working in partnership with Healthy Return to provide a gold standard protocol that gives UK employers access to the clinical data needed to return their team to work.