Sunday 21 March 2021

Uncertainty reigns over the effectiveness of Lateral Flow Testing in Schools

Perhaps the only certainty in schools in England since they opened fully to pupils on 8 March is that staff have once again stepped up to meet the latest challenges thrown at them as best as they can.

Otherwise, stress and uncertainty remain - from a lack of information from Exam Boards over this summer’s assessments, to a continued concern about levels of Covid transmission within schools.

Lateral Flow Testing was supposedly meant to help clarify the latter issue – at least in secondary schools. But the reality is that the lack of any genuine prior piloting of these devices in school settings means the school testing programme is being rolled out despite serious uncertainty about its likely effectiveness in identifying positive cases.

Is the ONS modelling wrong – or are LFDs simply failing to detect many positive cases?

A quick comparison of two pieces of official statistical evidence released at the end of last week shows that something doesn’t add up.

On 19 March, the ONS produced the latest weekly results from their ongoing ‘Infection Survey’. Their modelling, based on PCR test sampling that will include both asymptomatic and symptomatic cases, shows a continued welcome decline in the percentage of the UK population testing positive.

In Wales and most English regions the estimated positivity rates are still falling. However, rates may be levelling out in Northern Ireland and northern regions of England. In Scotland, it appears positivity rates are starting to rise again. As Independent SAGE have pointed out, this may well be linked to rising case numbers amongst primary pupils since a phased primary school return began in Scotland on 22 February.

However, the data that I want to concentrate on here is the estimated positivity rate for young people in the secondary school age range. The ONS estimate, for England only, is a positivity rate of 0.3% or 1 in 333 testing positive.


Separately, on 18 March 2021, the Government released data on the results from Lateral Flow Devices (LFDs) in schools, and some other community settings, from 4 to 10 March.

The sharp increase in LFD Testing carried out on secondary school students after 8 March is shown in the following graphs from the LFD report:

Analysis of the data provided shows that “2,762,775 tests on secondary school children were reported to have produced 1,324 positives. This is 0.05% or 1 in 2087 pupils testing positive”.
The ONS estimate suggests 6 in 2000 secondary school students should test positive, but LFDs have found a positivity rate of only about 1 in 2000. 

Even taking into account that some positive cases might be identified symptomatically without a LFD, that's a very significant discrepancy. Is it because the ONS modelling is wrong – or because LFDs are missing the majority of cases? The evidence suggests the latter is far more likely to be the reason for the discrepancy.

The 18 March 2021 Report itself reports that the LFD data “should be treated with caution whilst the understanding of the data and its quality improves”. This is in part owing to the fact that individuals may report more than one test and that some results may not be reported – but there is a more concerning underlying issue and that is the reliability of the LFDs in comparison to PCR testing, particularly in a school setting.

Lateral Flow Devices are not reliable enough to be trusted with school safety

From the very outset last summer, when Ministers came up with their “Operation Moonshot” plan for mass testing, its own advisers in the Scientific Advisory Group for Emergencies (SAGE) warned that “the cheaper, faster tests that will be useful for mass testing are likely to have lower ability to identify true positives (lower sensitivity) and true negatives (lower specificity) than the tests currently used”.

However, a clinical evaluation went ahead that claimed that “Lateral Flow Tests are accurate and sensitive enough to be used in the community, including for asymptomatic people”. However, a closer reading of the University of Oxford evaluation report shows that, while the Innova LFD test had a sensitivity of 79.2% (156/197) for all PCR positive individuals when used by laboratory scientists, this fell to 57.5% (214/372) when carried out by self-trained members of the public. This, of course, is how school staff have now been asked to conduct the testing.


A further two-week pilot of mass testing using the Innova devices was carried out in Liverpool. It only confirmed concerns over the accuracy of the Innova tests. A Liverpool University Report on the Pilot concluded that “the Innova SARS-CoV-2 antigen lateral flow device sensitivity was lower than expected (based on the preceding validation studies) at 40% but identified two thirds of cases with higher viral loads”.

This was confirmed to the Government in a paper presented to the 70th meeting of SAGE on 26 November 2020 that said “emerging evidence from Liverpool is that the lateral flow tests being used are not as sensitive as had been expected from the test validation”.


The data shows that LFDs are likely to miss a majority of positive cases in a school setting

The 40% sensitivity estimate – even lower than the sensitivity rates reported in the initial Oxford University clinical evaluation report - is explained below. Only 28 of the 70 cases detected by a PCR test were detected by the Innova Lateral Flow Test:


This second table shows how the majority of the cases that were not detected were for cases where the “Ct level” was high – or, in other words, where the “viral load” was low.

Table 2: Comparison of LFT site results and PCR results, by Ct levels

But asymptomatic children are more likely to have a lower viral load. Therefore, the sensitivity rates in a school setting may be even lower than the 40% estimate found in the Liverpool pilot.

In short, the initial evaluations of the Innova tests in practice suggest that they will fail to find the majority of cases in our school students and that “false negatives” will be common.

Of course, as staff are already finding, explaining to a student who has been told they are “negative” that this may be a false reassurance - and that they need to maintain social distancing, mask-wearing and all the other necessary mitigations, becomes more difficult.

(The unreliability of the tests also means that there may also be “false positives”, which could lead to children isolating without good reason, as explained in other articles).


So where are the scientific studies into the use of Innova tests in schools?

So, could the discrepancy between the ONS modelling (6 in 2000) and the results so far found in schools with LFDs (1 in 2000) be down to their lack of sensitivity when being used on young people in a school setting (or indeed, a home setting, as will soon be the case) ?

Scandalously, there is no clear data available because the Government failed to carry out any proper pilot into their use in schools. For example, the original Oxford University evaluation listed the settings in which the Innova tests had been trialled and their results compared with those from PCR tests:


But, as the table shows, where school settings were involved, none of the results were checked against PCR tests at all!

The Government claim they then carried out a further “pilot” into the use of Innova tests in schools. Indeed, Schools Week has reported that part of their “flimsy” evidence backing up their use of the Coronavirus Act to prevent Greenwich council closing its schools, was a claim that closing schools would prevent them using “testing programmes” – and that two Greenwich schools were then “involved in a pilot testing programme”.

But, as an article on the DfE blog makes clear, this pilot was about trialling the use of LFDs to “minimise staff and student absence” by offering them the opportunity to “remain in school and be tested daily rather than self-isolate when they were identified as COVID-19 contacts”. Were the DfE happy to allow participants to ignore their legal responsibilities to self-isolate under their own Government’s legislation? It was certainly without the clearance of the MHRA, the Medicines and Healthcare products Regulatory Agency as also revealed by Schools Week and discussed on my blog in a previous article.

Instead of trialling an unsafe procedure which they were then forced to abandon, the Government missed another opportunity to compare the results from LFDs with those from PCRs. Instead, schools are being expected to run a testing system that has had no serious prior evaluation about its appropriateness in such a setting.


Do not draw false reassurance about transmission in schools from LFD results

Sadly, there is a risk that the low number of positive cases detected through LFDs will give a false reassurance about the amount of transmission taking place in schools.

For example, I was disappointed to read the Director of Public Health for Lancashire, where I am a member of the NEU Branch, saying that "thankfully, the positivity rate in our schools remains extremely low. Between Monday, March 8 and Sunday, March 14, 47 tests taken by secondary pupils were reported as positive, from more than 71,000 tests”.

For all the reasons explained above, this is a false conclusion to draw. Actual positivity rates, and transmission risks within schools, may be far greater, particularly in those areas where local infection rates remain of real concern.

The table below, which I have compiled from official Government data, shows that on 13 March, at the end of the first week of full opening of schools, 34 English Lower Tier Local Authorities had infection rates of over 100/100,000 population over 7 days – and in most of these areas, rates were increasing. Looking at the full UK data, then Merthyr Tydfil and Anglesey in Wales, plus several Scottish Local Authorities, also have similarly worrying high infection rates.


And, while Lateral Flow Testing in schools may be missing many positive cases, Government data nevertheless shows that the numbers that are being recorded are also on the rise. This is a further indication that, just as was expected, infection rates in schools are, indeed, starting to climb once again.



Despite all the good work that is being done with vaccination, the risk of a further spike in infections remains. We must continue to fight for the mitigations necessary to reduce transmission risks in schools and their local communities.

Sunday 14 March 2021

Defend the Right to Protest, Oppose Sexual Harassment and Violence

The response to the abduction and murder of Sarah Everard has highlighted the growing determination, particularly amongst young women, to challenge the endemic sexual harassment experienced by 97% of them.

That gender inequality and violence is rooted in our unequal society, a society which trade unionists and educators can help organise to change. But the shocking scenes in Clapham last night haven’t only exposed the growing threat to the right to protest against such injustice and inequality. These events have also exposed the hypocrisy of politicians who either supported - or failed to oppose - the draconian legislation used to declare peaceful vigils as ‘illegal’ and who are preparing to do the same when the Police, Crime, Sentencing and Courts Bill goes to Parliament tomorrow.

Sexism in Schools

A 2017 NEU survey confirmed the sexism and sexual harassment that young women and girls encounter daily in schools. For example, almost a quarter (24%) of female students at mixed-sex schools reported that they had been subjected to unwanted physical touching of a sexual nature while at school. Sexist language and gender stereotyping were also commonplace. Yet only 14% of students who had experienced sexual harassment said they had reported it to a teacher.

The NEU has called for consistent and ongoing action from schools and Government to challenge sexism in schools. The number of young women that took part in the vigils that did take place over the weekend showed that many are ready to take a stand against the gender inequality and sexual harassment they have suffered.

Covid

Women have again been hit hardest by the pandemic. Schools, where women make up most of the workforce, face further cuts and job losses, particularly amongst support staff. Schools have been left to fully open without the mitigations needed to protect safety in cramped classrooms with poor ventilation.

Given the ongoing risk of rising community infections, it has been understandable that some people have questioned whether public protests should take place. But the risks of infection are considerably less in outdoor environments than the indoor ones like schools and workplaces that the Government insists are “safe” to attend. If the Police had liaised with vigil organisers, a safe and socially distanced event could have been held in Clapham.

The Right to Protest

Instead, the Metropolitan Police used the draconian powers handed to them in the Coronavirus Act. Police were filmed manhandling and arresting young women in scenes that showed a complete lack of understanding as to why so many had gathered together.

As Unite the Union have said in response to these events: "Women gathering in memory of a woman whose life was taken were doing so responsibly, in respectful memory. This grief should have been honoured, not violated” “There is also a very concerning move to limit freedom of protest that will be before parliament this week. We urge those alarmed by the scenes this evening to join with us and voices across civil society to speak as one in defence of our rights to peaceful protest, to support democracy and to keep the powers of the police in check."

Trade Unions must use their strength to oppose injustice and inequality

A few months ago, UNITE successfully challenged in the High Court another attempt by the Police to use the Coronavirus Act to prevent legitimate protest, in this case the right to picket outside your workplace during strike action.

Trade unions have always relied on protest to defend our members from inequality and injustice. Unions have also been at the heart of many of the gains won by women against the sexism and oppression inherent in our society.

Trade unions and trade unionists must now come together to support those wishing to protest against sexual harassment and gender violence and to make sure that the right to protest is defended for all.


Monday 8 March 2021

Williamson's longer school opening plans must be firmly opposed

THIS CALLOUS GOVERNMENT has made clear that its “thank you” to essential workers will be a further attack on our pay and conditions. 

European Commission/EACEA/Eurydice, 2018
For NHS staff, their ‘reward’ has been a derisory 1% pay award. For school staff, Education Secretary Gavin Williamson is suggesting schools need to operate with longer days and shorter holidays. 

This proposal is nothing to do with helping children. The Tories’ continued school cuts, alongside their reckless rush to full school opening, show that they regard schools primarily as a childcare service, not an educational one. 

Extending hours will not improve education

Extending hours will not improve education. Children, even more than adults, get tired. Concentration will not be maintained. 

As it is, pupils in England already spend longer in school than the global average. They also get shorter summer holidays too

OECD (2014): How much time do students spend in the classroom?
Compare England with Finland, consistently regarded as one of the highest achieving education systems:

Hours of compulsory general education over 9 years (equivalent to Key Stages 1-3):

Finland: 6327 hours                       

England: 7904 hours

Length of school year:

Finland: 187 days                            

England:  190 days

Length of summer holidays:

Finland: 10-11 weeks                    

England: 6 weeks

Instead of even more time enduring the “exam factory” conditions imposed on our schools by League Tables and Ofsted, school students after the pandemic need a ‘recovery curriculum’ that prioritises their well-being.

For their social development, children need leisure time and parents need time with their children. That means better pay and shorter hours, not the other way around. Youth and play services should be funded to provide additional support - but these have been slashed by Local Authority cuts.

School staff workload is already driving them out

The Government knows that over 20% of new teachers already leave the profession within their first two years of teaching. That rises to 33% within the first five years. If the Government succeed in imposing even greater working hours, staff turnover will increase even further, damaging education.

Government figures also show that teachers are already working over 50 hours a week. Support staff are also pressurised into unpaid overtime too. Instead of conditions being made worse, they need to be improved. That’s why one of the ten key points in my DGS campaign is for a National Contract for all school staff that sets a genuine limit on overall working hours, not just teachers’ ‘directed time’.

Organise national action to defend staff and education

Under current contracts, school employers could not enforce a longer working day or year. Any move by Ministers to try and impose changed contracts must be firmly rejected.

Such an attack could not be fought school-by-school. Unions need to boldly respond with a clear warning that, if the Government tries to enforce worse conditions, we will organise national action to defend staff and education.


I've also turned this post into a short campaign video. Please share with your colleagues via this YouTube link: