Posts Tagged ‘global health’

How many people will die from COVID-19?

Tuesday, April 14th, 2020 | Health & Wellbeing

Huge variations in estimates mean that we are 25% of the way through this to 2% of the way through this. All of this underscores the desperate need to start wide-scale antibody testing so that we can make evidence-based decisions on how we fight coronavirus.

The number of people likely to die depends on two factors: how likely you are to die when you get it (IFR) and how many people you will spread it to (R0). Below, I’ll explain both of these and run the numbers based on current estimates.

How many people you will spread it to

R0 represents how many people an infectious person will give it to. With seasonal flu, this is typically around 1.3. With highly infectious disease, such as measles, this can be as high as 9. Anything below 1 is great because it means the disease will slowly disappear as anything less than 1 means you are not even passing it on to one other person.

The Lancet has given an early estimate that COVID-19 at 2.35. But other studies have suggested it could be as high as 5.7.

The amount of people you infect is also dependent on the percentage of the population that are vulnerable. If half the population is immune because they have already had it or because they have been vaccinated, you can divide R0 by two. The number of people you infect is actually R0 * percentage of the population that is vulnerable (R0S).

R0 is important for two reasons. First, the higher it is, the faster it will spread. We can artificially suppress the number to be lower by using things like social distancing and lockdowns. If we can get it down to 1 we can control the situation. This is easier to do at 2.35 than it is at 5.7. The problem with social distancing is that it only artificially suppresses the outcome. Once you end the social distancing, the number jumps back up and the whole process starts again.

Second, it defines the number of the population that need to be infected or vaccinated before the disease will start to disappear. At 2.35, we need around 60% of the population to be immune before the number drops below 1. At 5.7, that means 80% of the population.

How many people die from it

The second factor is how deadly the disease is. If you haven’t followed the coverage too deeply, you might think the death rate is anywhere up to 3.4%. But this is not the case. What you’re looking at here is the case fatality rate (CFR), which is the percentage of people who test positive and then die.

This is quite high in some countries that are not bothering to test anyone and quite low in countries that are widely testing. But nobody is pretending it is the infection fatality rate (IFR), which tells you of the people who get it (tested or not), how many of them die. This we can only poorly estimate because we haven’t tested enough people.

In the UK, we know we are missing a lot of people because we are only testing those admitted to hospital (plus Prince Charles), and the results from testing in Iceland suggest that 10-50% of people are asymptomatic.

Estimates on the IFR vary. In an article in The Lancet, Imperial put it as high as 0.66%. Oxford University, however, put the figure much lower, estimating it to be somewhere between 0.1% and 0.36%.

Combining the variables

Here is the data modelled at for both an R0 of roughly 2.36 (60% of the population required to develop immunity) and for 5.7 (80% of population).

Country UK Italy Spain France
Population 67,801,000 60,483,000 46,750,000 65,235,000
60% of population 40,680,600 36,289,800 28,050,000 39,141,000
Deaths at 0.1% IFR 40,681 36,290 28,050 39,141
Deaths at 0.36% IFR 146,450 130,643 100,980 140,908
Deaths at 0.66% IFR 268,492 239,513 185,130 258,331
80% of population 54,240,800 48,386,400 37,400,000 52,188,000
Deaths at 0.1% IFR 54,241 48,386 37,400 52,188
Deaths at 0.36% IFR 195,267 174,191 134,640 187,877
Deaths at 0.66% IFR 357,989 319,350 246,840 344,441

A few things should be noted: first, this only calculates the point at which the disease starts to disappear. It won’t disappear overnight. Even if we get R0S down to 0.8, that still means that if 10 people get it, they will infect another 8. It’s on it’s way out but it is still throwing a few punches.

Second, if you want to be an optimist, you could say the IFR could be even lower. In the early days of swine flu, we were talking about high death rates (1-2%) and, in the end, it turned out to be 0.02%. This makes sense from a psychological point-of-view. Much better for a researcher to overestimate and say “sorry, it wasn’t that deadly after all” than to fail to raise the alarm, let everyone die and say “sorry, turned out it was super dangerous and it’s my fault everyone is dead”.

Other exit strategies

There are two other ways this could end. One is that it magically goes away over summer. Trump is still hoping for this option, I think, but even if this did happen, it may well just come back next winter.

The other exit option is a vaccine. Experts have said this is still 18 months away (12 if everything went perfect). But, importantly, this is just to deliver the vaccine. There is a difference between developing the thing and embarking on a nationwide or worldwide immunisation campaign. We have PPE equipment and COVID-19 tests now, for example, but getting them to the people who need them is still a logistical nightmare taking months.

So, we’re probably looking at two years until we’re immunised. For this to save lives, we would have to artificially suppress R0S to less than 1 for that entire time, which means two years of varying degrees of lockdowns and social distancing.

Whether this can work depends on how easy it is to suppress the virus. If South Korea continues to limit their deaths to a handful per day, they could keep the total number down to 2,000. New Zealand seem to be doing even better. How well this will work in the long-term is unclear; China is now battling a second wave of foreign infections, for example, and normal life is far from resumed in any of these countries.

Conclusion

Somewhere between 40,000 and 400,000 people in the UK are likely to die with COVID-19.

At the best-case scenario, we could be in for another three weeks of grim death counts before the virus starts to disappear forever.

In a worst-case scenario, we’re 2% into this, which will either see us go through a full year of this many deaths per day or a two-year-long lockdown while we hideout waiting for a vaccine. Neither of these options is appealing because it involves a lot of death, or in option B, two years of social isolation, mental health problems, suicides, drug and alcohol abuse, lack of a healthcare system, missed cancer screenings, job losses, domestic abuse, children not getting their education and the many other social costs.

All of this underscores the need to start large-scale antibody testing to confirm what the IFR is. Once we know that, we can start making evidence-based decisions about what the plan should be.

What is the law regarding exercise during COVID-19

Saturday, April 4th, 2020 | Sport

I’ve seen a lot of confusion about what we can and cannot do, exercise-wise, during COVID-19. That’s not surprising because what the law says, what the government guidelines say, and what Michael Gove has suggested are all different. In this blog post, I’ll break it down.

You can read Coronavirus Act on Parliament’s website. Which you probably should do, because I have no legal training and am in no way providing any kind of indemnified legal advice.

Can I go outside to exercise?

Yes. In order to leave your home, you need a reasonable excuse. The law (in England) then lists these reasons and includes “to take exercise either alone or with other members of their household”.

Can I go outside to exercise with other people?

Not unless you live with them, as the law says you can only go either alone or with members of your household.

Can I go out more than once per day?

Yes, you can. The law does not prohibit this.

However, where possible, you should avoid this. The government guidelines (which are guidelines, not laws) ask us to keep it to once per day and while it is not illegal to go out more, it makes sense for us to follow the guidelines.

Note that this specifically applies to England: in Wales, you are legally limited to going out once per day for exercise.

Is there a limit as to how far I can go?

No. You can go as far as you want. Neither the law nor the government guidelines, place any restrictions on distance.

That said, it makes sense to stick to your usual routine. If you try a 200-mile ride for the first time and end up exploding and needing someone to come pick you up, that is someone else having to travel.

Do I have to keep it to a maximum of one hour?

No, neither the law nor the government guidelines specify any kind of limit.

I think this may have come from a press briefing where Michael Gove said he expected people would be running for 30 minutes to an hour and encouraged people to stick to their regular routine.

Sticking to your regular routine makes sense, as explained above, so if you don’t usually exercise for more than an hour, I wouldn’t start now. But if you usually do long runs and rides, you are free to continue doing so.

Can I travel somewhere to start my exercise?

Some people have been travelling to national parks to exercise in the middle of nowhere. Can you do this? Probably, but you probably shouldn’t.

The law says you can go out to exercise, and the government guidelines don’t explicitly ban driving to a park either, but the government has said that you should avoid doing this during press briefings.

The concern is that more cars on the road, means more potential collisions, taking up hospital resources. Therefore, unless there is a specific reason you cannot exercise from your home, you should start from your front door.

COVID-19: Running Vallance’s numbers

Friday, April 3rd, 2020 | Health & Wellbeing

Patrick Vallance previous said he thought the UK would need around 60% infection rates in order for a country to develop natural immunity. As discussed in today’s government press briefing, he’s also quoted as saying 1 death represents 1,000 cases, confirmed or not. This is just a rule of thumb as we do not have enough data to know for sure.

Based on those numbers, we would be looking at around 36,000 deaths in Italy, 28,000 in Spain and 41,000 in the UK. It should be noted that, as previously discussed on the blog, we don’t really know what the death rates are, but some people have placed it higher. Anyway, that disclaimer over…

If we assume the midpoint will line up with the peak (and I don’t know if that is the case), there is some good news on the horizon. Based on current death rates, both Italy and Spain would reach their peak in 5 days (which is from yesterday, because it’s yesterday’s WHO data, so 7 April).

The UK is more difficult to predict. Based on the current death rates, we wouldn’t hit the peak for another 40 days. But, that death rate is likely to continue to increase further as it has been doing all week. If it doubled, that would half the time to 20 days (still a pretty grim prospect).

There is a bunch of stuff that could throw this off. Valance’s numbers could be incorrect. The peak may not lead up with the midpoint. And the social distancing may slow down the whole process, or even move us back to a containment phase if things went spectacularly well.

COVID-19: Where are the green shoots?

Tuesday, March 31st, 2020 | Health & Wellbeing

Today’s government spoke of “green shoots” and the idea that things might be getting a little better in the number of infections, which will have a knock-on effect later down the line. Unfortunately, that “down the line” could be a long way away.

This graph includes today’s provisional figures for Italy, Spain, UK, France and the US.

Italy and Spain are still rising, and while deaths per day are not increasing, they’re not decreasing, either. Italy is now three weeks into its lockdown. Most other countries, including France and the UK, seem to be following the same curve. The UK is still ahead of Italy at this point and by an increasingly large margin.

If the US figures are accurate, they have had the worst single day of any country without this entire crisis. But their reporting is a bit patchy, so it’s plausible that some of the deaths from yesterday were only recorded today.

The case for ending the lockdown

Sunday, March 29th, 2020 | Health & Wellbeing, Religion & Politics

The COVID-19 pandemic is one of the major challenges of our time. Many of us would advocate for evidence-based policy: we should let science guide us on the best course of action. Unfortunately, a complete lack of evidence for our current approach means the way forward is unclear.

The evidence for the lockdown

At first glance, it seems self-evident that implementing a lockdown will reduce deaths. If we all stay at home, it will reduce the transmission of the disease. In theory, this should allow us to spread the disease out over a longer period, and thus avoiding the healthcare system becoming overwhelmed.

Unfortunately, the evidence does not support this view. A Cochrane Review from 2011 concluded “there was limited evidence that social distancing was effective, especially if related to the risk of exposure.”

At the moment, we don’t even understand how dangerous COVID-19 is. As Dr John Lee notes in his article in The Specator, the lack of testing means the mortality stats are meaningless. We’re comparing deaths to confirmed cases, but the untested cases are anywhere from three times as many to three hundred times as many if a recent study by Oxford University is to be believed.

This is confounded by COVID-19 being a “notifiable disease”, meaning that a death could be reported as COVID-19 when a patient actually died of something else. This seems highly plausible given the average age of COVID-19 deaths is 79.5.

As Professor John Ioannidis points out, due to the lack of evidence, the policies we implement could hinder rather than help.

School closures, for example, may reduce transmission rates. But they may also backfire if children socialize anyhow, if school closure leads children to spend more time with susceptible elderly family members, if children at home disrupt their parents ability to work, and more. School closures may also diminish the chances of developing herd immunity in an age group that is spared serious disease.

Even if we somehow did concede there was some evidence for social distancing, we do not need to confound this idea with a lockdown. You can implement social distancing: such as getting people to work from home and banning large gatherings, without implementing a lockdown in which nobody is allowed to leave their house.

Further, even if social distancing did turn out to reduce infection rates overall, we need to look specifically at how it affects the elderly and vulnerable. It could be that young healthy professionals can lock themselves away and avoid infection, but those who require carers coming in and out of their home, or those who need regular medical appointments, cannot. Another example of how social distancing can harm, rather than hinder because the natural immunity we would otherwise develop from the age-groups at the least risk is never built up.

Ultimately, then, the evidence for social distancing is not substantiated. It could be that the models from Imperial College London are correct. But they may also be utterly incorrect. And that is serious as I will explain below.

Social costs of a lockdown

A lockdown is a serious thing in itself. It violates both Article 3 and Article 13 of the UN Declaration of Human Rights. If you are a Brexit-voter who supported leave because you were tired of human rights, you might like the sound of that. But most of my friends are fellow lefties who quite like human rights.

You could argue that is worth it temporarily to protect public health. And maybe it is. But we need to take all of the consequences into account.

These vary from the (arguably) mild: people have had their lives put on hold. They are not allowed to do the things they enjoy, like seeing the people we love. And doing the things we love: whether that is music festivals, triathlons, pub quiz nights or basically any hobby that doesn’t involve sitting on your sofa.

And continue up to the very serious:

  • Children are being stripped of their education. It’s impossible to expect parents to homeschool to the standard of professional teachers, and so much of education is the social education of interacting with peers and the school system.
  • Some children only get hot meals in school.
  • University students who are paying £9,000 per year tuition fees are not receiving their education
  • The cost to people’s mental health of being socially isolated and not going outside as much.
  • The resulting increase of suicides.
  • The transfer of healthcare resources from other conditions to COVID-19. Doctors and dentists are no longer offering appointments and operations for non-life-threatening but nevertheless debilitating conditions have been cancelled
  • The tidal wave of anxiety from people wondering whether they have a job tomorrow, or already having lost their job
  • The self-employed who find their income has suddenly disappeared and that they are not eligible for government support (which covers nowhere near 95% of self-employed people as the Chancellor claimed)
  • The already-overstretched police services admitting that they will only be investigating the most serious crimes because they will be too busy enforcing the lockdown
  • The domestic abuse victims who we have locked in a building with their abuser, and given their furloughed abuser nothing better to do than sit around and drink.
  • Drug and alcohol users who are in recovery but now more likely to relapse.

These are really, really bad.

People who have flouted the social distancing rules have rightly been called callous towards more vulnerable members of society. But we need to be careful not to fall into the same trap. To dismiss the social costs because our mental health is not suffering, because we have not lost our job, or because we don’t have children who spend years working exams they are now not allowed to take, nor even say goodbye to their lifelong school friends, is a privilege many other people in society do not enjoy.

As Lee puts it, “the moral debate is not lives vs money. It is lives vs lives. It will take months, perhaps years, if ever, before we can assess the wider implications of what we are doing.”

Weighing up the costs

Some young people have died from COVID-19 and that quite rightly tugs the heartstrings. But emotion is very different from evidence. And the evidence from Oxford University shows that the average age of those dying is 79.5.

Life expectancy in the UK is 81. That’s a loss of a year and a half, which is a serious and significant difference. I would be heartbroken if I lost my grandmother 18 months prematurely.

But we have to weigh that against the real and serious damage we are doing to everyone in society. Imperial’s modelling, which has formed much of the basis of the current strategy, predicts that social distancing and lockdowns will have to continue intermittently but indefinitely while we wait for a vaccine. Said vaccine will take at least 18 months to develop, even if everything goes smoothly, and that is before we even start the even bigger hurdle of global immunisation.

If we truly are looking at a 2+ year timescale, the cure would seem worse than the disease. With the average life expectancy of a COVID-19 victim only being 18 months, the majority are likely to die of natural causes in the meantime, doomed to be cremated at a funeral that nobody is allowed to attend.

Worse still, it may be that, as many commentators have predicted, social distancing and lockdowns are not sustainable for such a long period of time. As a result, the pandemic will continue to flare up and kill just as many people, and all our suffering will have been in vain.

If the pandemic magically goes away in the next 12 weeks, then you can make a solid case for the lockdown. And let’s pray that it will. But if not, and we have to keep the suppression methods in place until the vaccine arrives, or they simply fail, we will have wasted more of everyone’s lives than we saved for the 0.25-1% of people who, already at the end of their life, had it cut slightly shorter.

Ultimately, we do not know what the correct answer is. A lack of testing and a lack of data means the conclusion is unclear. And yet, based on that, we are implementing a policy with dire consequences for education, mental health and quality of life.

Editing notes: reflecting back, I’m not sure 81 is a fair assessment of life expectancy. Although it is the average life expectancy in the UK, once you reach 79.5, you are likely to live longer than 81. How we adjust for this is unclear, though. The ONS suggests that a 79-year-old will live another eight years. But this is for a typical person, and we know that most people survive the virus but that rates of mortality are particularly high for people with underlying health conditions. Therefore, in order to adjust, we would need to know the life expectancy of a 79-year-old with underlying health conditions. Unfortunately, that is data we do not have.

COVID-19: The curve starts here?

Friday, March 27th, 2020 | Health & Wellbeing

At first glance, yesterday’s figures do not look too bad. Both Italy and Spain seemed to have stopped shooting up. But the provisional figures from today (Friday) mean that they are both going to set new heights tomorrow.

It’s a bad day for France and the UK, too, who both had record days.

Here is the other big change: I have also started tracking Netherlands. Why? Because Netherlands are sticking hard to the herd immunity strategy. This was mentioned in the UK and, depending on who you believe, was always a side-effect of the plan, or the plan until Johnson’s critics spooked him into adopting the current approach. Tracking Netherlands may provide some evidence as to how effective the lockdowns are.

Let’s look at total deaths.

The first thing to explain: I have now capped this at 60 days, rather than expanding it as the dataset grows. This makes it easier to see the curves in the early days. It does mean we are now missing the past five days from China. But the line is basically flat (they are still having a handful of deaths per day, though).

Second thing: I have included the UK’s provisional figures from today in the report. That makes the graph look much scarier. We are the blue line. Until this point, we could hold out some hope that our line would follow the green line (China) and not the red line (Italy). But at this point, it looks like we are accelerating on “the European trajectory” as we could call it.

And, to state again, the UK is ahead of almost every other country was on day 15. This includes Italy. Spain is the only exception, who are way ahead of everyone. Ignore the single dot from Netherlands, that is erroneous data. Currently, they are roughly in line with other European countries.

COVID-19: UK by region

Thursday, March 26th, 2020 | Health & Wellbeing

It was a bad day for Spain yesterday who reported more deaths than Italy. Italy, on the other hand, maybe showing signs of levelling off. The UK had a fairly good day, but that may be due to underreporting: the BBC said the timeframes were chopping and changing, which might explain why we had few deaths yesterday but over one hundred today.

Here is the new graph for today. It shows cases across England broken down by NHS region, with the separate nations (Scotland, Wales, Northern Ireland) also getting their own slice of the pie.

A third of the cases are in London. But that is not abnormally high: they have 13% of the population and the most international travellers passing through. Still, might make you think twice before taking the tube. Otherwise, it is fairly well spread out across the country.

COVID-19: Black Tuesday not so black?

Wednesday, March 25th, 2020 | Health & Wellbeing

I mean, we have definitely had better days. Spain, France, the UK and the United States all had their highest ever death count yesterday. And bear in mind that I am only tracking seven countries. But there is a silver lining: although Italy had a bad day, too, it was not as bad as two days ago.

It is still too early to say whether the UK is going to follow Europe or China. But it would seem odd if it did follow China given we have been taking at best similar, and at worse, much more lax measures than the rest of Europe, while China went into lockdown early and did a lot of testing.

The problem is that we are still earlier on in this than everyone else. We’re on day 12. Italy is on day 29, Spain is on day 17 and France is on day 18. At this stage, everyone except Spain was behind us. Early indications from the NHS is that today wasn’t too bad, but it’s only 9pm, so we’ll have to wait and see.

COVID-19: Age group stats

Tuesday, March 24th, 2020 | Health & Wellbeing

I’ve updated the graphs for today. WHO report on what happened yesterday, so when I say today, I mean the data the WHO published today, but it’s actually yesterday’s data. And yesterday wasn’t too bad. Italy continued to decline for the second day in a row. And when I said the borderline for good for the UK was 331 deaths, we came in at 335, so pretty close.

That said, based on today’s media reports, we know that the UK, Italy and Spain are all having a really bad today. So, tomorrow the graphs are likely to look terrible.

Anyway, onto today’s graphs. I took the figures from Imperial College London on the likely mortality rates of COVID-19. These are adjusted based on many cases not being reported, and for a UK/US healthcare system.

I want to preface the following by sating: just because you have a low risk of dying, does not mean you can go around doing whatever you like. You can spread the virus without knowing and you could end up spreading it to someone with underlying health conditions, who are much more likely to die. And that would make you a murderer, morally, although not legally.

Ok, the graphs. First, your risk of dying is low.

Even if you are in the 80+ age category, you only have a 27% chance of needing hospital treatment and a 9% chance of dying. That is much higher than the everyday life of course! This is a serious thing that kills people. A lot of people.

But, for an individual’s risk, you have a 3/4 chance of being able to cope at home, and a 10/11 chance of surviving. Certainly not a Russian roulette game any of us would want to play. But it is good to know that our grandparents having a fighting chance.

Below, is the same graph but zoomed in. The X-axis only runs to 30%. This is not representative of your overall chances but means we can see it better.

In the lower age categories, the outcome looks rosy. If you are in your 30s, for example, you have a 3% chance of requiring hospitalisation and a one in a thousand chance of dying.

I don’t know what percentage of the population have underlying health conditions. But I imagine it increases with age and maybe around 3% for someone in their 30s and may well be 9% for someone in their 80s. If so, that would mean that COVID-19 typically only kills when you have underlying conditions. But I don’t have those figures, I’m speculating. The WHO has stressed that younger people are not invulnerable and they are literally the World Health Organisation, so we should listen to them.

It also seems likely that the stats for underlying health conditions are much higher than those percentages and that most people with underlying conditions are also fine. Or as fine as you can be when you have a nasty flu. As Chris Whitty keeps reminding us, the vast majority of people, even in “at-risk” categories, will get over it.

That’s all for today. See you tomorrow to talk about Black Tuesday :(.

COVID-19: What’s changed today?

Monday, March 23rd, 2020 | Health & Wellbeing

The WHO has now released today’s situation report. Here are some of the headlines:

  • China and South Korea are still seeing deaths, but not many.
  • Italy recorded 649 deaths, compared to 795 yesterday. It has dropped before and then continued to rise, though.
  • The US has reported 201 deaths today, doubling their total. As none were reported yesterday, could just be delayed figures?

Let’s update the graphs.

Deaths per day

Deaths per day graph

Let’s hope today’s result is a sign that Italy is turning the tide and not just an anomaly. On the other hand, let’s hope the US result is an anomaly based on delayed data and goes back to normal tomorrow.

My previous graph showed the incorrect figure for the UK yesterday, which I have now corrected in this graph.

Cumulative deaths

Cumulative deaths since the 10th death graph

Nothing terribly important to report here, I think. Italy and Spain are still on scary trajectories. It’s too early to say what is going on in the UK. We might follow China. But it is important to remember that Italy weas behind China until day 15. We’re only on day 10, so there is plenty of time for it to accelerate on Italy’s path.

Massively simplistic rules of thumb are a bad idea. But let’s make some anyway. It’s unlikely to start magically dropping at this point (see below), so anything below or around 331 cumulative tomorrow would be a good result. Anything significantly above that would be a bad result. And anything around the 381 mark would be a terrible result.

Social distancing has a delayed effect

One final thought: there is probably at least a 14-day delay between implementing social distancing and seeing any benefit. The virus has an incubation period, then five days of fever and coughing, then the respiratory issues kick in.

We implemented our first set of social distancing (telling people to work from home and not gather in groups) on Tuesday 15 March. That’s six days ago.

We implemented our second set, closing schools and telling people “seriously, stay away from each other” on Saturday 21 March. That was two days ago.

That means that we have 8-12 days of nobody was social distancing damage before we even get to the “we told you all to distance, not cough on each other in the royal parks” damage, which may or may not be resolved. What you do today affects what happens in the ICU two weeks from now.