We write to update you on our COVID-19 testing plans following the latest lockdown announcement. Before going into detail, we must apologise for our publication of a Department for Education template letter, which was sent to parents at the end of last term. The content of the letter was questioned by some parents, and it has subsequently been withdrawn from the DfE website (https://schoolsweek.co.uk/dfe-removes-highly-misleading-covid-testing-guidance/).

Our position as a school is that we will use Lateral Flow Tests as much as we possibly can, in order to help to make the school a safer place. It is important to note that the test is consent driven. We can only administer a test if both a parent/carer and the student (for those aged 16 or under) have given consent. It is therefore very important that when parents/carers fill out the online consent form, that they speak to their child about it. Sixth form students can give consent themselves, but it is still a good idea to for parents/carers to speak with them about the test. We currently have consent from around 63% of the lower school (years 7 to 11) and 72% of the sixth form. We strongly encourage all parents/carers to carefully consider participating in the testing programme if they have not already done so. In this week’s Worcestershire Head Teachers planning meeting, whilst uptake was very variable it was approaching 97% in some schools. The more participants we have, the greater the chances of identifying and isolating asymptomatic positive cases.

Rationale behind national mass testing

We do understand that there have been some doubts expressed in the press about the accuracy of Lateral Flow Tests, which has led some families to have doubts about the value of participating. Before outlining our plans for testing, we will therefore say a little about the background to the LFT programme. The evidence considered by parliament in making a decision to proceed with mass testing, based on the Liverpool pilot with 100,000 people, can be found here: https://post.parliament.uk/mass-testing-for-covid-19-using-lateral-flow-tests/ . As with any pilot programme, the crucial part is in the interpretation of the results. The key extract from this report is:

The table below sets out the scale of false negatives and positives using a test with the sensitivity and specificity of the Innova test* in a testing population similar in scale to the serial mass testing pilot in Liverpool (100,000) using COVID-19 prevalence rates reported for the city when mass testing began on 6 November (300 people per 100,000). Using these figures means that the chance of being infected is 0.3%. This table shows the overall predictive accuracy if 100,000 people are tested with test with 76.8% sensitivity and 99.68 % specificity:

Infected with SARS-CoV-2Not infected with SARS-CoV-2TotalPredictive accuracy of test
Test positive230 (true positive)319 (false positive)549(230/549 x 100) = 42%
Test negative70 (false negative)99,381 (true negative)99,451(99,381/99,451 x 100)

= 99.9%

 

The test is very good at identifying almost all the people who do not have the infection (99.9%) but is less good at identifying the people who do (42%). This is why follow-up PCR tests are important to confirm positive results, but this will not catch the 70 people who test negative even though they are infected.

*we will be using Innova tests

What this means in practice is that if someone has a test and tests negative, we can be 99.9% sure that they are not infectious and so it is safe for them to return to the school population. This means that for every 1,000 tests we carry out, we will miss one infectious person. If we don’t test, we will miss all of them. However, of those who test positive, the PCR test will confirm that only 42% are actually carrying the virus, hence the need for confirmation with a PCR test. The other 58% will have been inconvenienced for a day or two, before returning back into the school population. This seems a fairly small price to pay to have a test which confirms with 99.9% accuracy that a student or staff member is safe to work within the school population without presenting an infection risk to others.

For those of you who might be interested in the science behind the tests, you may find this paper in Nature magazine of interest: https://www.nature.com/articles/s41551-020-00655-z .

Lateral Flow Testing plans at The Bewdley School

Following our advertisement for staff on 22 December, we have conducted online interviews and now have 18 paid staff and 3 volunteers currently undertaking NHS online training for testing centre staff. All 5 senior leaders undertook the training at the end of last week and have been engaged in setting up our testing centre. We have today taken delivery of 4 specialist testing booths where students and staff can take samples in privacy, and have set up our testing centre in the gym. Work is ongoing in the Youth Centre and as soon as all services have been tested and updated as needed, our testing centre will be relocated there.

The experience for our students and staff should be relatively rapid, and whilst the sample collection may be uncomfortable it will be brief. For those undertaking a test, the process will operate as follows:

  1. Registration for the test is with the NHS online test and trace system. You will be given a card with a QR code printed on it, which when scanned will take a smart device to the test and trace registration page. The purpose of this is to give your name and contact details, which the platform will use to send you the result. Identification of the test taken is done with 3 identical barcodes. One will be fixed to your registration card, which you keep. Another will be fixed against your name on the register. The third you will take to the testing bay, to be fixed to the back of the Lateral Flow Device used to test your sample. If you do not have a smart phone, support will be offered to register your test.
  2. Once registered you will be asked to wait in a socially distanced waiting area. You will be expected to wear a face covering at all times. When called you will go to a private testing booth where you will find a chair, written instructions and a mirror. You will pass your spare barcode through the window in the booth to the Processing Operative, who will give you a tissue and a pre-packaged swab. You will first blow your nose, then check in the mirror the location of your tonsils. There will be someone to help you do this of needed. The tissue goes into the bin at your feet, as does the wrapping around the swab.
  3. Testing is self-administered. You will need to open your mouth as wide as you can, as you do at the dentist or doctor’s surgery. You must rub the swab gently against the tonsil on each side of your mouth at least 3 times for each. When putting the swab into and out of your mouth, you must be careful that it doesn’t touch anything other than your tonsils. You then swab your nose by pushing the swab into one nostril only, until you feel a slight resistance (about 2.5cm). The swab is then rotated 5 times slowly and removed.
  4. You then pass the swab through the window into the prepared vial of testing fluid that the processing operative has ready for you. You will be asked to wait in the testing booth until the Processing Operative is sure that they have a sample for testing. You will then be told you can leave and the test is over. You will get your results via the contact details you gave to the test and trace website. If the result is positive, you will be informed by the school as soon as the result is available, and will need to go home and book a PCR test. Results typically take around 30 minutes to process.

It is our hope to introduce regular weekly testing for staff and students who are currently attending school. We then plan to test the whole school population when school returns, and to continue to use testing to help us to keep the school safe.