There is actually some good news emerging from the tragic gloom of the Covid-19 epidemic. Despite some relaxation of lockdown rules in recent weeks, markers of serious infection – hospital admissions and deaths – continue to fall. There are several reasons for this but undoubtedly a learning process has taken place and we now understand much more about the virus. This has completely changed the dynamic compared to when actions were first taken from late February to March. And yet watching the news now with reports of new case surges and local lockdowns it feels like we are stuck in a time warp.
One of the jokes doing the rounds on social media is a mock-up of the film, Back to the Future with the scientist character, ‘Doc’, imploring the film’s hero, Marty, not to select the year 2020 to travel to. For me, thinking back to the beginning of the year seems like a lifetime ago. Occasional news of a new infection in China was the only hint of what was to come. What was emerging though was very serious and vividly took over our screens when large parts of northern Italy succumbed to the epidemic. Detail was sparse, modelling was based on assumptions at the time and incomplete data from what the Chinese had released to the WHO. Understandably planning and action was based on ‘worst case scenarios’ and a template of lockdown in China was judged by the WHO to be successful.
Assumptions are exactly that. They are based on information available at the time but they should always be challenged and updated over time. Modelling based on early data should be revised as the picture changes.
In March, it seemed we were facing a virus which could affect all age groups. We thought it might kill anywhere between 0.7-3 per cent of those infected and had an R-value of 2 or more, suggesting quick spread and anything up to 80-90 per cent of the population being infected before a natural herd immunity state emerged. This was the picture at the time, garnered in good faith. And this was the origin of the now infamous Imperial College modelling of up to 500,000 deaths in the UK as a ‘reasonable worst-case scenario’. A fairly standard and stereotyped package of measures were prescribed across the world: lockdown, social distancing, hand-washing and subsequently mask wearing. This WHO advice was followed almost without exception around the world.
Move forward now to August and things become rather more complicated. From late March to May, there was a crisis. At its peak in early April almost 20,000 people were admitted to hospital in England in one week with Covid-19. There was no doubting the gravity of the situation. But the peak hit in early to mid-April. Since then, week on week admissions have been falling. Last week the figure was 321, with a current total of 523 people in hospital with coronavirus. To put this in context, in England there are just over 140,000 hospital beds in total. Thankfully deaths per day are in single figures. The numbers are very clear: serious infection from Covid-19 currently appears to be disappearing.
However, there is one number that has increased since May and that is overall PCR testing. In March to May, testing was not available in the community even if you had symptoms. The advice was to isolate, and coronavirus infection was generally assumed after a call to NHS 111 was made where the patient listed symptoms which matched those experienced by Covid patients.
Now testing has been ramped up dramatically. As a consequence, we have an announcement now almost daily on our news broadcasts of positive cases of coronavirus based on a PCR test. This identifies fragments of the virus but its relationship to infectivity is unclear. So we have stories of spikes of surges in positive cases either in the UK or abroad and the imposition of quarantine on returning holiday makers or partial resumption of lockdowns in local areas of high case numbers. Our reaction to a positive test is to isolate and quarantine or lockdown those in the vicinity to presumably prevent the further spread of positive cases. The measures undertaken now are not too dissimilar to those taken in March, albeit to a partially lesser extent with cases treated in this paradigm as a surrogate of serious infection.
Here we come to assumptions again. If one looks for a definition of what a case is, there is no absolute clarity. In fact, it could mean a number of things, ranging anywhere from a serious infection that puts a person in hospital right through to an asymptomatic person with a positive PCR test.
Infectivity to others is assumed, it seems, in all cases. But this is an assumption. We simply do not know how infective a person is when they are asymptomatic and simply show PCR positivity. Initially the WHO reported that transmission in such cases was ‘very rare’. Now that has been revised again. But what is clear is that there is a varying degree of transmission risk and not all cases are the same. Yet apart from hospital statistics of admissions and deaths, and recorded out-of-hospital deaths, we have little more information about what these cases are and the risk of wider and more serious infection. What is reassuring however is that even in areas of local lockdown, such as Leicester, there was no commensurate increase in hospital infection or death to go with the upsurge of positive tests.
To echo the words of the government, we do need to ‘stay alert’ regarding coronavirus. We are still learning. But what we have seen in the last couple of months is different to what has gone on before. Local lockdowns, quarantine and other partial measures have been re-imposed to curb the spread of positive cases but is that truly necessary? We appear to be working from the serious infection template of March where the purpose of the measures was to prevent death not prevent a positive PCR test. This is a new dynamic. When there is a serious risk of harm by not undertaking a preventative measure then there is an overwhelming narrative to do so and accept a degree of harm that may be caused by it, such as a temporary loss of cancer screening or other health measures. Now when the link between a positive Covid-19 case and serious infection is less clear, what is an acceptable level of intervention on a healthy population? And when answering that question, we must factor in that such an intervention can do harm.
I believe these are vital questions that must be asked and fully discussed. Decisions and actions taken in March were based on information and data that is different to now. The strategy should therefore be re-visited. The current issue is in people who are generally younger and without co-morbidity. Some will have symptoms and clear infectivity but others may not and we know that for whatever reason few need to be admitted to hospital. Balance that against the continued partial closure of health services and ongoing mental health effects of the whole crisis and it is clear our current policy is causing harm. I do not know if there has been any new rigorous attempt to try and weigh up the benefits and risks of what we are currently doing.
In the Back to the Future films the characters were able to re-programme their DeLorean to move to another time and therefore escape crisis. We need another approach to move forward. Short of a vaccine, we seemingly have no end game and the reflex action of lockdown is appearing increasingly disproportionate to the danger currently faced. A new conversation is needed.