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From Monday 16 August, people who are double jabbed or aged under 18 will no longer be legally required to self-isolate if they are identified as a close contact of a positive COVID-19 case.
Prof Lawrence Young, Virologist and Professor of Molecular Oncology, Warwick Medical School, University of Warwick, said:
“This change comes at an interesting time when daily case numbers remain high and there is increasing evidence that double vaccinated individuals can still get infected with the delta variant and spread infection to others. It is very likely that this change will fuel increased levels of infection and that this will lead to further hospitalisations and deaths. It will add to the current sense of complacency and the view that we are over the pandemic. The fully vaccinated and under-18s will only be advised to get a PCR test if they are a close contact of a positive case and not expected to isolate while they await the results of the test. They will, however, be advised to wear facemasks and limit contact with others. This is extremely unlikely to happen. It will be interesting to see how many people stick to the isolation rules. While accepting that the disruption caused by the ‘pingdemic’ is not sustainable, it is important to recognise that the virus is still circulating in the population and that the more infectious delta variant has changed the equation.”
Dr Peter English, Retired Consultant in Communicable Disease Control, Former Editor of Vaccines in Practice, Immediate past Chair of the BMA Public Health Medicine Committee, said:
“Firstly, my understanding is that this change in the rules is only supposed to apply to people who are “asymptomatic”. To me, that would mean feeling completely well, without even a runny nose or a mild cough. But I’m not sure this has been emphasised adequately. People who are fully vaccinated and who yet are infected will usually have “attenuated” – milder – symptoms; but they may be just as infectious as people who were not vaccinated. Just less likely to realise they are infectious. We also need to update the symptoms lists – newer variants do not have the same distinctive set of symptoms as the original variants, and more often present in a way very similar to a “common cold” or “flu”.
“We have been living with this pandemic since early 2020, and of course everybody would like to be able to return to normal. People are tired of restrictions; and businesses want to be able to fill their premises with paying customers without irksome restrictions – indeed, without sufficient support from the state, many will go under if they cannot do so.
“We still have very high rates of Covid-19 transmission – 288 cases per 100,000 population are testing positive daily (over 2,000 per week) according to the current “dashboard” data (https://coronavirus.data.gov.uk/details/vaccinations).
“Various experts have previously recommended that we can go back to normal when case numbers have fallen, ideally (as in Germany e.g.1,2) to fewer than 10 cases per 100,000 population per week. We are clearly a long way from that; and the decline in case numbers we saw recently seems to have plateaued – case numbers are no longer falling. And before we know it schools will return, and more socialisation will take place indoors, both of which will further drive transmission.
“There are, broadly, two ways to control a communicable disease. The first is to ensure that people who are likely to be infectious do not spread the disease to others. That’s what self-isolation is about. Arguably, we have done far less well than we should have done at ensuring that potentially infectious people self-isolate. Lockdown is an extreme example, where, because you cannot identify potential cases in a timely way, the only way to reduce transmission is for everybody to self-isolate.
“Policy decisions have undermined our ability to control the pandemic, and are the reason why case numbers in the UK have been so much worse than in many similar countries. For example, recommendations for identified contacts to not self-isolate until and unless you have a positive test result (which comes after you will no longer be very infectious anyway); and failing to adequately support people to self-isolate, so that people, instead of being rewarded for doing their civic duty by self-isolating when symptomatic lose out on income and opportunities.
“The other way to control a communicable disease is to ensure that it cannot spread, because there aren’t enough people it can be spread to, because everybody is immune. “Herd immunity”3. But with the highly infectious variants that have emerged, this may be impossible to achieve, even with high vaccination uptake in the groups most likely to transmit the infection to others4,5.
“In practice both approaches are generally used in tandem, with case rates in the general population being held low through vaccination, but with case-finding and isolation of cases and contacts when there are cases or outbreaks (e.g. of measles).
“The government’s argument now is that vaccination has weakened the link between cases and severe illness causing hospitalisation and death. This is true. People who are fully vaccinated are definitely less likely to get seriously ill or die, even with the delta variant. If your main goal is to reduce the load on the NHS (and on mortuaries), the high level of vaccination in the groups most likely to need care or to die will, indeed do this.
“Vaccination means that people are less likely to be infected; and if they are not infected, they cannot infect others. And they are less likely to be infectious (possibly because the duration of infectiousness is smaller6. (There is some evidence that those who are fully vaccinated and then infected have, initially, the same viral load as people who are not vaccinated and likely therefore the same infectiousness; but they clear the virus more quickly, so they are not infectious for as long, and therefore infect fewer other people.)
“Somebody who is fully vaccinated – and fully asymptomatic – is, indeed, less likely to become infected, and to infect others, if they are in contact with a case. It reduces the risk of transmission.
“But the delta variant is so much more infectious than previous variants that it will be very much harder for people who are not immune to avoid being infected; and, as I mentioned previously, transmission rates are still extremely high.
“Reducing the requirement for contacts to self-isolate if they are fully vaccinated will inevitably increase transmission; the question is, to what extent? And is now the right time?
“Being fully vaccinated does reduce the odds of somebody being infected and transmitting the infection. But I would be much happier if we were to reduce the odds of transmission further, by waiting until we had driven case numbers much lower. The BMA was arguing, over a year ago, that restrictions should be agreed in advance and tiered, according to local case rates – and the government followed our advice (the German government, that is!). If we used this sort of approach to drive case numbers down, hardly anybody would be “pinged” to self-isolate, because case numbers are so low; and we would be able to fully support those who are fully infectious. I fear that the UK government is reducing these requirements before there is sufficient certainty of how effective vaccination will be at reducing transmission, knowing that it vaccination alone is unlikely to be sufficiently effective, and this will extend the duration of the pandemic and cause avoidable death and disease.
“And removing the requirement for contacts to self-isolate if they are under the age of 18 amounts to driving infection in under-18s, so that most are infected and will require some degree of natural immunity. Given that we do not yet fully understand the long-term consequences of Covid-19 infection, this is a huge gamble. Even if only a small proportion of them suffer long-term or permanent damage, ensuring that nearly all young people are infected (as they will be, given our failure to vaccinate them or to invest in mitigation in schools), will inevitably mean large numbers of them who will be impaired for a long time, or for life.
“Personally, however, I am very unconvinced that this policy change is a good idea, certainly now while we have very high case numbers, and if we had low case numbers it would not be necessary anyway.”
Prof Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:
“It is very difficult trying to move away from what are felt to be unnecessary restrictions. What is undoubtedly true is that being more than 21 days after receiving a second dose of a vaccine does not mean you are protected from catching the delta variant of the virus if exposed to it.
“Over the next few weeks more and more people will become aware of those who experience this. In those with two doses (and you might expect to have breakthrough disease immediately after a second dose, before its efficacy has kicked in fully), they may be infected with or without symptoms and they will also have the ability to pass on the infection.
“CDC in the US has said: “Fully vaccinated people with Delta variant breakthrough infections can spread the virus to others. However, vaccinated people appear to be infectious for a shorter period: Previous variants typically produced less virus in the body of infected fully vaccinated people (breakthrough infections) than in unvaccinated people. In contrast, the Delta variant seems to produce the same high amount of virus in both unvaccinated and fully vaccinated people. However, like other variants, the amount of virus produced by Delta breakthrough infections in fully vaccinated people also goes down faster than infections in unvaccinated people. This means fully vaccinated people are likely infectious for less time than unvaccinated people”. [https://www.cdc.gov/coronavirus/2019-ncov/variants/delta-variant.html]
“There are considerable dangers both to individuals and to the community if people think this pandemic is over from 16th August. Perhaps individuals should be prepared to self-isolate but perhaps for fewer days than the current 10 day period, but removing all restrictions may not be a good idea. It is quite likely that at least some of the UK population may realise this and follow sensible measures rather than casting off all restraints.”
Dr Jeremy Rossman, Senior Lecturer in Virology, University of Kent, said:
“The new rules on self isolation for doubly-jabbed COVID contacts are unfortunately inadequate for effectively stopping the transmission of Delta variant. The government says that “the protection from vaccines replaces the need for contact isolation”, this is not completely true. The vaccines are highly effective at reducing COVID infections and virus transmission; however, they are not perfect and breakthrough infections do occur (especially with Delta variant) and fully vaccinated people experiencing a breakthrough infection can still transmit the virus. Thus it is still essential to identify people that are infected and ensure that they isolate to stop virus transmission.
“For COVID contacts, this can be achieved through self-isolation as a precautionary measure or though testing. The current recommendations state that “double-jabbed individuals and under 18s who are identified as close contacts by NHS Test and Trace will be advised to take a PCR test as soon as possible to check if they have the virus”. Testing can indeed identify infections, even with Delta variant, but advised is not the same as required and a single PCR test is insufficient to stop transmission for two reasons. First, the turnaround time for a PCR test can be multiple days, if someone is infected then they risk spreading the virus while they wait for their test results. Instead they should either isolate while waiting on the results or to use a rapid test. Second, a single test is not sufficient to rule out infection following an exposure. Someone may be negative on a test one day (due to being early in the infection process) but then test positive on the next day. Without guidance specifying the need for repeated testing (and when those tests should be taken) there is a real risk of virus transmission from any infected, doubly-jabbed COVID contacts. The government provides guidance for repeated testing for healthcare workers, but this requirement is needed for all identified COVID contacts that are not self isolating.”
Dr Stephen Griffin, Associate Professor in the School of Medicine, University of Leeds, said:
“This policy might be sensible in the scenario where we have achieved high vaccine coverage within the entire UK population, but, critically, in the context of a low level of circulating infection.
“However, we are not in this place, currently, and the Delta variant has changed the terms of the game. Sadly, government policy hasn’t adjusted to adapt to the new pandemic.
“Whilst breakthrough infection remains rare, we are already in a different place with respect to how Delta spreads compared to alpha — strategy should change accordingly.
“Present policy disregards clinically vulnerable people, children, long COVID, and the border policy is a perpetual failure.”
Prof Sheila Bird, Formerly Programme Leader, MRC Biostatistics Unit, University of Cambridge, said:
“Unclear whether evidence-based as I’m not sure that the evidence (which NHS T&T must hold) is in the public domain. Going forward, NHS T&T needs to take a post-marketing-of-policy stance and report publicly on the % of those alerted contact who do/do not seek timely PCR-test and the attributes (e.g. gender, age-group, symptomatic, degree of vaccination {nil, single jab, double-jab & with which vaccine) that inclined them to seek a prompt PCR. For those who are PCR-tested, we need to know % positive and, for POSTIVES, the distribution of ct-values (as proxy for viral load) which is likely to differ by symptom-status and vaccination-status inter alia.”
Dr Jonathan Pugh, from the UK Pandemic Ethics Accelerator, and Senior Research Fellow in Practical Ethics at the University of Oxford, said:
“It is only justifiable to continue restricting people’s liberty in the name of public health if doing so is necessary and proportionate.
“We now have some data to suggest that the vaccines are effective in reducing transmission (https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/fully-vaccinated-people.html). In particular, one study published in late June suggests that household transmission was approximately 40 to 50% lower in households of index patients who had been vaccinated 21 days or more before testing positive, than in households of unvaccinated index patients (https://www.nejm.org/doi/full/10.1056/NEJMc2107717).
“If a vaccinated individual poses a low enough risk of transmission, then it may no longer be necessary to restrict their liberty in order to prevent harm to others. The moral justification of releasing double vaccinated individuals from self-isolation requirements therefore depends on whether vaccination means that the self-isolation of these individuals is no longer necessary to significantly reduce the risk of onward transmission.
“To this point, requiring the self-isolation of all close contacts of people who have tested positive for COVID-19 has been an effective way of reducing transmission. But it is not a very specific strategy; some close contacts of an infected person may not themselves be infected, and they may not pose a threat of transmission to others. The key question here then is, how much does vaccination reduce the likelihood that a given close contact of an infected individual poses a risk of harm to others?”
All our previous output on this subject can be seen at this weblink:
www.sciencemediacentre.org/tag/covid-19
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