COVID-19: How is this wave different from the first?

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This blogpost looks to examine the differences between the first and this second wave, as cases of COVID-19 are on the rise again. It also looks at the data from the areas that have been under the extended restrictions for the past few weeks to see what impact there has been on the number of positive cases. We also consider what we still don’t know and what might be different now.

Think back a couple of months. We were talking about stages out of lock-down, pathways away from the dramatic and frightening attack from, and consequences of a contagious new pandemic. We were relaxing just a little. We were in the new normal.

Renewed restrictions

The First Minister announced on 7 October that restrictions implemented from 22 September, that households would no longer be able to meet up in each other’s homes across the country, would be extended. The restrictions were already in place in Glasgow and some neighbouring authorities, and these have now been further supplemented as cases and hospitalisations continue to rise. The restrictions further limit how people can meet and gather, particularly in licensed premises across the central belt, affecting around half of Scotland’s population. The ‘rule of six’, and the prohibition of meeting in one another’s houses remain in place nationwide.

New restrictions mainly affect the central belt because this is where cases are rising fastest. The government have published an evidence paper that provides the rationale for the latest restrictions as well as detailed, up to date data.

While we are being reassured that we are not going ‘back to March’, our social lives do seem to be closing in again. Being unable to visit friends and family at home was, for some, possibly the hardest aspect of the lockdown. Now, too there are renewed restrictions on the ways many of us are allowed to socialise and interact.

The First Minister made her decision on 22 September, based on the impact of local lockdowns put in place at different times over recent weeks. We decided to use the data to see and compare what changes had been in various areas in the number of new infections since July. The charts below show positive tests per 100,000 population in various areas, with the dates of local lockdowns marked. We have included Edinburgh where no local lockdown had yet been imposed, though this has now changed, and Edinburgh is included in the new additional restrictions.  Note of course that it is not possible to attribute the any change in infections purely to the date of local lockdown – many factors are at play, such as the start of the new university term, and we cannot know what the data would look like if these actions had not been taken.

A comparison of positive test by 100,00 of the population for selected local authorities.

So what is different?

Are we in the same place as we were in March? A second wave was always predicted and now we know much more. It is hard to resist looking at the spikes on the various graphs at the height of the pandemic and making a direct comparison with the way those spikes appear now. The only one that would tell us that things are as bad would be seeing a comparable rise in daily deaths and admissions to intensive care. These rises are not a foregone conclusion. The government’s evidence paper, published 7 October, says that there are now 262 people in hospital with COVID-19, with the largest numbers in hospitals in NHS Greater Glasgow and Clyde and NHS Lanarkshire, and that:

“Latest figures show there were 25 recently confirmed COVID-19 cases in ICU, so numbers are still very low compared with the first peak in April when there were around 200.”

We see from the government evidence that there has been a 79% rise in admissions in the week to 5 October. The real numbers remain small at present, but the steep rise cannot be ignored.

This difference has been attributed to the age profile of those becoming infected. The chart below shows the age profile of those testing positive, from March to October, and that the age of those testing positive is clearly younger now than during the first wave in March, and potentially harder to contain within these groups.

The age profile of those testing positive is younger in the second wave.

One of the headline factors that is worrying policy makers is the rising ‘R’ rate. Putting the modelling to one side, it is an easy measure to understand in that once it goes over ‘1’, we can all understand that the virus is spreading again. Lockdown brought it down well below 1, but now it is estimated to be between 1.3 and 1.7 in Scotland.  This has risen from between 1.1 and 1.4 in the last two weeks. This is still, at the moment, well below the number estimated for February/March 2020 when it could have been as high as 5.8. Even so, the rise in confirmed cases over the past few weeks has shown that this virus still has the capacity to infect many people.

The following sections highlight a number of factors which are very different now.

Testing

Testing has been an issue across the UK since the beginning of the pandemic. Many more tests are being carried out in the general, symptomatic population, as well as through the contact tracing, test and protect policy, whereas early on, testing was very targeted and narrowly focused.

As the most recent data shows, the number of tests, particularly in regional testing centres, has risen sharply, despite the well-covered recent issues with people being unable to access tests and the problems with the ‘test and trace’ system being overwhelmed and not working properly in England.

The more tests that are carried out, the more positive results will be recorded. So, are we really seeing more cases, or is the rise mainly due to increased testing? Another way of considering the relationship is the positivity rate – the proportion of positive cases against those tested – now at 13%, or the doubling rate of cases, which, across August and September was an average of 9 days (to 30 September), down from 11 days (to 23 September (see page 1 of government evidence paper). However, comparisons with March/April are problematic because testing volumes and strategies, as well as knowledge about presentation of the illness have changed so much.

Testing in April averaged around 1,900 per day, having increased from 1,700 on 1 April to 4,400 on 30 April. Testing in September had increased to around 16,500 a day on average.

Looking at the latest SPICe blog on COVID-19 data in Scotland, we see that at the beginning of April the 7-day average was around 700 people being tested in Scotland (i.e. this is not per week). On 2 September the 7-day average was over 14,000, albeit that numbers tested have dramatically reduced since then to around 5,500.

Testing has significantly increased since April, from on average 1,900 per day to 16,500 per day in September.

We also need to ask how good a gauge a comparison of testing was or is when so many people with and without (two key) symptoms were never tested in the early months.

Following the controversial practice of moving many older people from hospital to care homes which some say contributed to around half of all deaths in Scotland occurring in care homes, testing protocols changed dramatically. Now, no-one can be moved to a care home without testing and 14-days in isolation.

Testing symptomatic people for the presence of the active virus, which is what we are receiving data on, is not really a good epidemiological indicator because we do not know who has had the virus without symptoms or with more unusual symptoms. Anti-body testing of one form or another provides a much clearer picture in the long-term of the status of the virus within the population, and this relies on good surveillance testing by public health authorities. The UK Government have recently invested in one million antibody tests for the purpose. The Scottish Gvernment updated its testing strategy in August, and discusses surveillance testing. The Office for National Statistics (ONS) has been carrying out surveillance testing, extended, since August across the four UK nations. An initial survey was established in May. The ONS COVID-19 Infection Survey looks at the prevalence of symptomatic and asymptomatic COVID-19 infection in the community, how this varies over time and how this varies by population broken down by age, ethnicity and geography. Results are published weekly on the ONS website.

Personal Protective Equipment (PPE)

We have not heard much recently about the availability of PPE for all those who require it. But remember, it was a huge challenge in the early weeks. Problems included:

  • adequate supplies to all front-line NHS and care staff
  • time and training for fitting PPE correctly
  • ensuring that the right people were able to access the right equipment continuously
  • PPE protocols for what was required when.

It appears that these supply issues have been fully resolved along with regularly updated iterations of health protection guidance in Scotland on many issues.

We know much more about how to treat people who are seriously ill with COVID-19

Covid presented a massive clinical and logistical challenge in March that saw an overwhelming response, such as the rapid establishment of ‘Nightingale Hospitals’, albeit that they weren’t in the end really required, because intensive care units were able to cope.  The contract for them has been extended and they have been repurposed and remain available. An article published in May, described the ‘transformative disruption’, which brought in new ways of working and the empowerment of frontline staff that seems to have surprised everyone. This learning remains in place.

Doctors in intensive care units are no longer dealing with many of the unknowns of the disease that they experienced in the early days. While there remains no vaccine and no bespoke treatment for COVID-19, NICE and SIGN have published a range of evidence-based ‘rapid’ guidelines on the diagnosis and treatment of COVID-19. None of this was available in March.

Corticosteroids, dexamethasone and hydrocortisone and Remdesivir, an anti-viral medicine have been found to have a role in treating some of those affected. Clinical trials, by NHS Blood and Transplant services are also underway in the use of antibody-containing convalescent plasma to treat severely ill patients. This means that people entering hospital now, could be offered convalescent plasma as part of the trial.

Risk factors

It was clear from the earliest days that the most vulnerable, and the most likely to die from COVID-19 were elderly. It also became clear that those with underlying conditions, especially cardiovascular conditions, for example, also suffered worse outcomes. Likewise, people from black or other ethnic minorities are more vulnerable.  In addition, those from the twenty percent most deprived areas in Scotland have been found to be more than twice as likely to have died from COVID-19.

With all the caveats around testing processes noted above, it is interesting to note that the biggest rise in positive cases we are seeing is in the 29 – 45 age groups. Worryingly though, in the older age groups cases are rising again. The data that aren’t being published are the positive tests in the 0-15 age group. However, these are available in the government’s evidence document to provide the rationale for the latest restrictions, and cases in the 0 – 29 age group are showing the biggest rise in new cases over the past week (see Table 1 page 3).

Hospital and ICU admissions

This could tell us how badly people are being affected, telling us how many people are not able to manage their symptoms at home. However, how these data are reported has changed in recent weeks making it difficult to make comparisons between then and now.

We are seeing numbers being admitted rise sharply, now that we are beyond the initial lag between infection and the deterioration in symptoms. Given the change of demographics affected, we still don’t know at this stage what proportion of people will need intensive treatment, and how many will manage symptoms at home.

One thing we are aware of now is that even mild symptoms, across many age groups, can lead to ‘long-covid’, a set of chronic symptoms such as fatigue, chest pain, breathing difficulties and pain. It is estimated that around 10% of sufferers will continue to have symptoms beyond three weeks. This has turned into months for some. This means that hospital admission is not necessarily a useful indicator on the impact on the NHS or individuals in the medium to longer term. What it does tell us, is that being younger, and not being hospitalised is not necessarily a reason to feel reassured.

Deaths

Again, it is just too early to draw any conclusions about the effect of either the rising positive cases, or the measures taken, on the death rate from COVID-19. To attempt to calculate case fatality rates or infection fatality rates (IFR) and make any comparisons is fraught with uncertainty – the known unknowns. These might be fewer now, because of increased testing. These rates don’t change, but they do become more accurate over time, as more testing is done and data increases The Scottish Government discuss the calculation of the IFR in their modelling publications.

In the week to 5 October there were 18 deaths where someone died within 28 days of a first positive test. The government evidence paper tells us that there are currently 2.2 deaths per day per million people in Scotland from COVID-19. However, it is still early days in the current phase because the course of someone’s illness might be protracted, and death can occur some weeks after admission.

However, while knowing the proportion of people who might die from an infection can be seen as an indicator of risk, we now know that the risks from infection are not binary – that you either recover completely or die, because a proportion of people infected will go on to endure symptoms longer term.

Wider health impacts

The impact of long-term symptoms on the health and care services, as well as the growing concerns about other, wider impacts of COVID-19 on these services and individuals are yet to fully unfold, but are being tracked by Public Health Scotland using existing datasets tracking unscheduled care. That is, emergency, out of hours and unplanned care rather than planned operations and treatment. We have heard also how there has been a drop in cancer referrals in Scotland. Researchers in Glasgow have produced a paper taking a broad view of health impacts and how they might be mitigated.  In addition, while measuring collective well-being or population-wide psychological stress/distress created by restrictions is not easy, it is clearly an issue that policymakers will return to as the pandemic develops.

What will be difficult to decide is where the tipping point is – or was – between attempting to mitigate the direct harms and spread of COVID-19 and the longer term psychological and chronic health impacts and costs. These are in addition to the wider societal and economic costs.

Anne Jepson, Senior Researcher, Health and Social Care