Ross Clark

So is this the big turning point? Markets certainly seem to think so. No sooner had news broken that the vaccine being developed by Pfizer and German firm BioNTech is 90 per cent effective, the FTSE surged by 5 per cent. Given that the US Food and Drug Administration (FDA) has suggested that any vaccine that proves to be more than 50 per cent effective could be licensed, this suggests the vaccine will go on to be approved around the world. Any vaccine that proves partly effective will be welcomed with open arms by a world which largely remains in lockdown or semi-lockdown. But does the reality live up the surge of relief which has gone around the world this morning?

The weekly ONS infection survey suggests that the rise in prevalence of Covid-19 in England has levelled off. Not only that, it suggests that the rate of new infections has actually fallen. In the week to 31 October, the ONS estimates that 618,700 people had Covid-19 — about 1 in 90 of the population. That was up from 568,100 the week before — a 9 per cent increase. However, it amounts to a stark slowdown on previous weeks. At that rate, it would take eight weeks for the number of people with Covid-19 to double — a long way from the doubling rate of eight to ten days which was observed in September.

If it wasn’t miserable enough being told that I have to spend the next month at home, now I have ‘Pete’ from Octopus Energy emailing me and asking if I would mind terribly turning off a few appliances between 4.30pm and 6.30pm. If fact, he says, if I can halve my energy usage during those hours he’ll give me a half price deal on the rest.  Apparently it’s because the National Grid has issued an ‘electricity margin notice’ for those hours – basically a plea for Britain’s remaining coal and gas power stations to turn up the power and squeeze a little more energy out of their plants.

The government’s £12 billion test and trace system has been described by its scientific advisory committee Sage as making a ‘marginal’ difference to the transmission of Covid-19. This is not least because test results are taking a long time to arrive — of tests conducted at testing centres in the week to 21 October, only 47 per cent of results were returned the next day. For home test kits, just 32 per cent of results came back within 48 hours. In the same week, test and trace only managed to make contact with 60 per cent of contacts reported to it.  But there is another factor that is central to understanding test and trace's effectiveness which remains obscure: just how likely are we to catch Covid-19 from a close contact anyway?

The graph presented by chief scientific officer Sir Patrick Vallance during Saturday’s press briefing suggested that, in the absence of a new lockdown, deaths from Covid-19 could reach 4,000 a day by Christmas. To put this scenario in context, deaths in the first wave back in April peaked at just over 1,000 a day. Back in spring, a pre-publication copy of Neil Ferguson’s paper — the Imperial College modelling of Covid-19 deaths which sent Britain into the first lockdown — was released, so we could all see the assumptions and reasoning behind it. Saturday’s graph did not even reveal the source of the 4,000 deaths a day claim — although it has subsequently been revealed to be a Cambridge/Public Health England (PHE) estimate.

In Britain this week we have had scientists at Imperial College warning that levels of antibodies in the population are dropping away fast, with only 4.4 per cent of the population showing them in September – far short of the 60 to 70 per cent government scientists believe is required for the epidemic to die away thanks to herd immunity. But it is a different story in South Africa, where two of the country’s leading virologists believe that parts of the country have achieved herd immunity. Speaking to Sky news, Marvin Hsiao of the University of Cape Town, said he couldn’t explain why infections in South Africa – which was one of the worst-affected countries in the world in the middle of the year – suddenly plummeted at the end of July.

Imperial College’s latest React study — an attempt to measure the spread of Covid by testing the general population — suggesting that the number of people in Britain carrying antibodies for the SARS-CoV-2 virus has dropped sharply over the past three months. This led a few headline-writers to run somewhat ahead of the facts. 'Covid immunity only lasts a few months,' claimed one. The reality is a lot more complex — indeed, one of the possible interpretations of the Imperial study is that more people have some level of immunity than has previously been believed. The React study tested 365,000 adults between late June and September, using a self-administered finger prick test to detect for the presence of antibodies.

Worse tales have emerged during the pandemic than that of the ‘Florence Three’ – Rhys James, Quinn Paczesny and Will Castle, who have all now returned home to Britain after 61 days incarcerated in a hotel in the Italian city. Some might say a couple of months stuck in Florence could have been a blessing – and so it might have been, had they not each been stuck in solitary confinement and fed microwaved mush, with no more chance to go out to a trattoria than to visit the Uffizi. But what stands out about the story of the Florence Three is not so much their plight, but what it tells us about Covid-19 tests. The three men, who are aged between 20 and 23, met in Northern Italy while teaching English over the summer.

That the lockdown had a terrible impact on the nation’s health — in ways other than just Covid-19 — is becoming clearer by the day. But just how bad was it? According to a study by the London School of Hygiene and Tropical Medicine, delayed and cancelled breast cancer treatments will cause between 281 and 344 additional deaths. For colorectal cancer, there were an extra 1,445 to 1,563 deaths, lung cancer an additional 1,235 to 1372 deaths and 330 to 342 more oesophagal cancer deaths. A University of Leeds study estimated that there have already been an extra 2,085 deaths from heart disease and stroke as a result of people not accessing timely medical help.

What percentage of people who are infected with Covid-19 will go on to die of the disease? The dramatic response to the pandemic on the part of almost all governments around the world has been based on the idea that Covid-19 is a far more lethal disease than seasonal flu, which is often quoted as having an infection fatality rate (IFR) of 0.1 per cent. The World Health Organisation (WHO) is often quoted as claiming that Covid-19 has an IFR of 3.2 per cent — a claim that goes back to a press conference in early March when it, in fact, said that the case fatality rate (CFR) at that stage was 3.2 per cent.  The CFR is the division of known deaths by known cases — the denominator omitting the many cases that have not been confirmed by diagnosis.