Covid-19 Tests

Coronaviruses are a large family of viruses which may cause illness in animals or humans.  In humans, several coronaviruses are known to cause respiratory infections ranging from the common cold to more severe diseases. The most recently discovered coronavirus causes coronavirus disease COVID-19.

People can catch COVID-19 from others who have the virus. The disease can spread from person to person through small droplets from the nose or mouth which are spread when a person with COVID-19 coughs or exhales. These droplets land on objects and surfaces around the person. Other people then catch COVID-19 by touching these objects or surfaces, then touching their eyes, nose or mouth. People can also catch COVID-19 if they breathe in droplets from a person with COVID-19 who coughs out or exhales droplets. This is why it is important to stay more than 2 metres (6 feet) away from a person who is sick.

1. A high temperature- this means you feel hot to the touch on your chest or back but you don't need to measure your temperature.
2. A new, continuous cough – this means coughing a lot for more than an hour, or 3 or more coughing episodes in 24 hours (if you usually have a cough, it may be worse than usual).
3. Fatigue
4. Shortness of breath

If you suspect that you have been exposed to the coronavirus due to you having recently travelled to a high-risk country,  you think you may have come into contact with someone who has Covid-19 or you have symptoms then you can do the swab test between 1-5 days post exposure.

However, symptoms may not appear for up to two weeks after you have become infected with the virus. This means that it is possible to spread the virus without having any symptoms.

If you would like to know if you have had Covid-19 already then the blood test may confirm whether or not you have had it.  

A blood sample should be undertaken 14 days or more following exposure or onset of symptoms. You should not test before this as even if you have contracted the virus and showing symptoms as you may not have produced enough antibodies for them to be detected by the test.

However, you can collect your blood sample at any time if you have not experienced any symptoms at all as some people may have had the virus but don't show any symptoms (asymptomatic).

The test involves taking a single combined swab of your mouth and then your nose - as used by the NHS.

It is a PCR test that detects the genetic information of the virus, the RNA. This is only possible if the virus is there and someone is actively infected. By detecting viral RNA, which will be present in the body before antibodies form or symptoms of the disease are present, the tests can tell whether or not someone has the virus very early on.

We provide an instruction leaflet with your test that details how you should take the test.

There are designated priority postboxes that will accept and deliver your Covid 19 test swab sample to The Doctors Lab, TDL, in London. If you click on this link the you will find the nearest postbox to you.

The antibody tests can be posted in any postbox.

Testing for COVID-19 antibodies may tell whether a person has been previously infected with SARS-CoV-2, the virus that leads to Coronovirus Disease (COVID-19).

You will need to produce a small blood sample using a sterile lancet that is enclosed within the test kit. The lancet pricks the side of your middle or ring finger and you massage a small amount of blood into the collection tube. Full instructions are supplied with the kit.

It is the Roche Diagnostics Elecsys Anti-SARS-CoV-2 assay which has been evaluated by Public Health England (PHE) as being suitable for detecting the production of COVID-19 antibodies from capillary blood samples.

Although both the Abbott SARS-CoV-2 IgG and Roche Elecsys Anti-SARS-CoV-2 assays detect IgG antibodies to SARS-CoV-2, the Roche assay is a total antibody assay and will additionally detect IgM antibodies, reporting both IgG and IgM as a total antibody result.

Both the swab tests and the antibody tests are completely legal to sell in the UK and have a special CE mark to prove their validity.

The PCR swab assays used at TDL show a minimum sensitivity of 98% and a specificity of 100%, with no cross-reactivity with other viruses.

The antibody tests have a minimum sensitivity of 97.4% and a specificity of 100%.

The tests are performed by The Doctors Laboratory, who provide quality UK accredited pathology services worldwide. The Doctors Laboratory (TDL) is a medically-led laboratory, established in 1987. It is the largest independent provider of clinical laboratory diagnostic services in the UK.

If you order before 4pm Monday to Friday then you will receive your test kit the next working day by our courier DPD. You will receive an allocated 1 hour delivery slot from DPD on the morning of delivery.

If you order on a Friday before 4pm then you can upgrade to a Saturday delivery for only £2. 

You will normally receive your blood test results within 24-48 hours and the swab test results within 48-72 hours of the lab receiving your test sample.

You can opt for a choice from 3 types of communication.

1) Open email

2) Email notification where you simply receive an email informing you that you have a message from Webmed. Then you log into our website with your email and secure password to receive your test results in your message centre

3) SMS notification where you receive a text informing you that you have a message from Webmed and then you log into your message centre for your results.

If you test positive

1. You must immediately self-isolate for a minimum of ten days to prevent spreading the virus to others. Anyone who has been in contact with you must self-isolate for 14 days.

2. You should then use the online  coronavirus 111 service here https://111.nhs.uk/covid-19/

   or  contact the NHS on 111 who will advise you on the next steps to take.

The immune response to SARS-CoV-2 continues not to be fully understood and the significance of having antibodies against this virus is not known.

Most patients who recover from coronavirus have been found to produce antibodies, but it is not yet known if an individual with a positive result showing presence of IgG levels following being infected with SARS-CoV-2 will be protected, either fully or partially from future infection, or for how long protective immunity may last.

This could mean that an individual who has a confirmed infection by PCR could have a negative antibody result; this could also be true if the blood sample is taken too soon, or too long after infection.

Therefore, you must still follow the social distancing rules to avoid catching it again or spreading the virus to anyone else.

If you haven’t experienced any of the Covid-19 symptoms then you’ve probably not had the virus.

However, if you have had symptoms then it’s possible that you may have had the virus but your immune response was low or your antibody levels may have dropped and are therefore undetectable.

The blood test only looks for the antibodies that are produced after you have been infected. If you have had a sufficient immune response then it will tell you if you've already had it.

You would need to take a PCR swab test to find out if you have a current infection that would make you infectious to other people.

As with all viral PCR assays, patients with very low viral loads are less likely to be detected. 'Not detected' results do not preclude infection with the SARS-CoV-2 virus and should not be the sole basis of a patient treatment/management or public health decision. Where there is a strong clinical suspicion of an early COVID-19 infection repeat sampling should be considered 24-48 hours later.