Those anxiously keeping track of the UK’s Covid-19 epidemic will have noticed something of a turning point in the past few weeks. Whether you call it a second wave or not, countries such as France and Spain are currently experiencing much higher levels of cases than the UK and there are signs that, as in the spring, Britain is lagging only a few weeks behind.
The number of confirmed virus cases declared each day in the UK has reached levels not seen since May, while the oft-quoted R number – a measure of the rate at which the virus is spreading – has risen above one, according to several estimates.
The government’s strategy of imposing local lockdowns seemed like a reasonable way of tackling the virus when it was present in only a handful of communities, but as more of these localised measures come into force and their limited efficacy becomes apparent, more draconian national restrictions could follow.
From the start of June onwards most areas of the UK had fewer than 10 cases of the virus per 100,000 people per week, but by the end of August this had started to drop. Now, less than a third of the country has negligible levels of Covid-19 cases.
At the same time, hospitalisations remain low and deaths below levels usually seen at this time of year. It’s difficult to know how worried we should be.
Here we assess the state of Covid-19 in the UK, and whether we are seeing the beginnings of a resurgence of the virus.
UK confirmed cases hit highest levels since May
The weekly rolling average of confirmed coronavirus in the UK topped 3,000 for three consecutive days last week, according to Public Health England. The last time this threshold was reached was in May – when cases were on their way down.
Tracking confirmed cases has always been a flawed method of measuring virus prevalence because it depends wholly on testing capacity. As capacity is added, more tests are carried out and more cases are likely to be recorded as a consequence.
However, there are signs that the recent rise in cases does indicate a resurgence of the disease. For instance, the percentage of tests returning positive has climbed above 1.5 per cent in recent days – a level not seen since the end of May.
The case-positivity rate tends to increase when cases are more prevalent in a country. To use a fishing analogy: if you are constantly filling your net when you bring it up, you know that there are likely to be far more fish out there that you are missing. But if you cast your wide net and are only getting a couple of fish, you can be confident that you aren’t in fertile waters.
This is confirmed through other estimates of Covid-19 prevalence. The Office for National Statistics carries out a weekly infection survey estimating the prevalence of the virus by combining targeted testing with a questionnaire. In the last two periods for which it has data, it recorded an increase in cases in the community.
This survey only covers the period to 5 September, but an alternative measure – provided by a symptom tracking app – confirms a continuation of the increase. The Covid-19 Symptom Study app, run by Zoe and King’s College London, predicts there are more than 50,000 cases of coronavirus in the UK today compared with around 22,000 a month ago.
It should be noted that this is still lower than the 90,000 cases the app estimated at the same point in June, and well below the two million cases predicted on the eve of the national lockdown in March.
It’s fair to say that cases are increasing at the moment but – even accounting for the current debacle over testing availability – it is likely they aren’t anywhere near levels during the peak of the virus in the spring.
The all-important R number
Case numbers on their own are only so useful in assessing where the UK is currently positioned relative to a second wave. They have to be assessed alongside the rate of increase as represented by the R number. This is the number of people that each infected person infects, on average.
As with case numbers, many different estimates of the R number exist. The Covid Symptom tracking app puts it at 1.2, while a separate study from Imperial College London estimates that it could be as high as 1.7.
The official government estimate is lower but, significantly, it also puts the figure as being probably above one (the range given is 1.0 to 1.2), indicating that the virus is spreading rather than receding.
An R number below one is generally a good sign, whereas an R number above one is only likely a bad sign if the number of cases in the given population is also high.
The researchers behind the Covid-19 Symptom Tracking app think we are in the latter situation. In their latest report, they write: “This uptick in [case] numbers is disturbing and if we don’t get the R value down in the coming weeks, we could be looking at another national lockdown.”
Local lockdowns are spreading (and not working)
One key part of the government’s Covid-19 strategy since lifting the full national lockdown has been to introduce more localised restrictions. The New Statesman has been tracking the likelihood of local lockdowns in our tracker, which is updated daily.
In the past two weeks the number of local authorities across the UK to have local measures imposed on them has increased to 27 as cases have risen. This means that more than 10 per cent of the UK – some 7.3 million people – are now affected.
At the same time that local restrictions are becoming less local, it is also increasingly apparent that they are not restricting the spread of the virus. Just seven local authority areas have had local restrictions removed entirely since stricter local rules were imposed, while Leicester is still in the top 20 areas of the country in terms of case rate, according to our local lockdowns tracker, despite being in lockdown since late June.
It seems that these local lockdowns are ineffective and this strategy may have to be abandoned for tougher national restrictions. The events of the past week have already led to a hardening of the law nationally, with social groups now limited to six people.
Whether you want to use the term “second wave” or not, another national lockdown would be much like a repeat of the events of the spring for the vast majority of the population.
Reasons not to panic – deaths and hospitalisations remain low
While many indicators are starting to show signs of growth again, we are yet to see a noticeable increase in the most important statistic: the number of people dying from the virus.
This could be due to several factors, including the age structure of those now getting the virus. At present, elderly people are not catching the virus to the same extent as they were previously, and instead younger people have been infected as schools and universities reopen. It is also true that some of the most vulnerable people in society may have already died during the first wave.
Acute respiratory outbreaks – including flu as well as Covid-19 – have been falling in care homes and rising in workplaces as the economy has reopened. In the week ending 6 September, there were almost as many outbreaks in workplaces (65) as there were in care homes (69).
It could, however, simply be a matter of time until deaths rise. They tend to lag behind confirmed cases and it generally takes around ten days for symptoms to worsen to the point where hospitalisation is required.
Hospitalisation figures are showing signs of increase, following several weeks of remaining steady despite cases soaring. They stood at 205 on 11 September – up almost 50 per cent from the 137 recorded a week earlier.
However, there are now more effective treatments for Covid-19 available – including the steroid treatment dexamethasone – meaning fewer hospitalised people will die than before.
Deaths as a whole (not just from Covid-19) are now below the five-year average in most settings (hospitals, care homes and other locations) but are still far above average in people’s homes, suggesting that knock-on effects of lockdown are contributing to mortality.
Are other countries a sign of things to come?
Using other European nations as a benchmark for what would happen in the UK proved eerily accurate in the early days of the epidemic, with France, Italy and Spain all a couple of weeks ahead.
France and Spain are, again, ahead of the UK in a resurgence in cases, with Europe being responsible for a significant part of the global increase in coronavirus. Spain has passed 200 new cases per one million people registered every day, breaking its record of around 170 new cases per million at the end of March.
France, Austria and the Czech Republic have also experienced a significant increase in cases over the past weeks. All, however, are yet to see a corresponding rise in deaths. Deaths could, of course, increase in the weeks ahead, but it is entirely possible that the UK could experience a continued increase in confirmed cases while deaths remain low.
Such a trend would pose a political dilemma for the government. It would be harder to justify the economic damage of another lockdown while deaths were not increasing – but doing nothing until there is a large number of deaths could also be seen as a reckless, and fatal, political gamble.
Ultimately, time alone will tell if the increase in cases in the UK marks the second wave of Covid-19. At present, the numbers are markedly different to those in the spring, but this could change quickly.
Watching how the increasing case numbers translate to hospitalisations and deaths in Europe in the weeks ahead will probably be the best indicator of what will happen next in the UK.