Covid-19: Has Italy turned the corner?
April 6th, 2020: four weeks after the start of the country-wide lockdown in Italy, and there are some stats we are all monitoring for a clear sign of the virus slowing down. Everybody is desperate to start discussing the next phase and move on from what is still a pretty dramatic time. There’s been a marked decrease in new confirmed cases and deaths, while Italy has been performing more and more tests every day, finding less and less positives. And more importantly the number of patients in intensive care has for the first time started to decrease, while the number of patients who made a full recovery is steadily increasing. The lockdown is working, but it’s probably much slower than most people were hoping for.
The significance of these days in Italy (and Spain, to be fair) shouldn’t be underestimated: most western countries struggle to take China or South Korea as an example of how the crisis was dealt with. Is it because we don’t have enough information, or enough capabilities, or because society here works in a different way? Or because it’s just too late? With Italy and Spain, the USA, UK, France, Germany, Belgium the Netherlands and several other countries in Europe and America are now well past the point when the virus could be contained, they are all speeding down the same very steep slope, and hopefully have prepared themselves for a long ride.
There are many questions: how long is it going to take to the most draconian control measures to show their effect? Is it going to be a very sharp improvement or a slow and prolonged one? And when can the toughest measures be relaxed? What measures should remain in place and for how long? What precautions will be required to avoid new outbreaks? The questions are concrete: businesses, shops, schools, support for families, freedom of movement, physical and mental health, life and death. Everyone is involved and it very much depends on how this crisis is managed and the time it takes to get to the other side.
Let’s look more in detail at the stats in Italy, and perhaps draw analogies with other countries.
- New confirmed cases and Deaths
New confirmed cases have decreased significantly both in percentage terms and in absolute terms. From over 20% per day of the first 2 weeks of March, (an astonishing exponential growth) to less than 4% average per day, over last week. In absolute terms, from around 6,000 per day in the fourth week of March, to an average of less than 4,500 per day over the last week.
The number of deaths has also decreased in relative and absolute terms, from an average of more than 800 over the last week of March, to less than 700 per day over the first week of April. After they peaked on 27 March to over 900, with a 1-week delay on the peak of new cases, they inverted the trend drastically and showed a continued decrease.
2. Number of tests and new cases
What is even more important, is that the reduced number of daily new cases, has coincided with a significant increase in the number of tests performed, which has been averaging at around 35,000 per day over the last few days. So effectively the rate of discovery of new cases has reduced significantly, from 25–30% of the 3rd week of March, to 12–14% of the last week. In other words, if last month we were discovering 1 new case for every 3 or 4 tests, now we are only discovering 1 in every 7 or 8 tests (for comparison, Germany has been finding 1 positive every 15 tests or so… we are getting there).
This is a sign that the spectrum of people tested has broadened significantly, and includes not only many more “negatives”, but probably also more mild cases of the disease, which should result in a reduced mortality rate over the next few days and weeks. This trend has already been visible over the past 2 weeks, with the mortality rate vs. new confirmed cases of 8–10 days before steadily decreasing.
For comparison, let’s look at the same chart on mortality rate for Germany (using the same scale).
Yes, I know. Germany is testing much more, tracing infected people’s movements and contacts, testing people at risk, and overall finding a large number of positives, but probably mostly mild cases or asymptomatics (people who wouldn’t have requested a test, in the first place). This could be a reason why the mortality rate is very low, under 3% even when compared to the confirmed cases of 8 to 10 days before, and at 1.6% on current confirmed cases. For clarity, mortality rates are also affected by the health system response to serious cases — the availability of intensive care infrastructure and high quality treatment, where certainly Germany excels.
All this doesn’t necessarily mean that the virus crisis will be an easier one for Germany — all this information about positives needs to be used, e.g. control measures can be more selective and effective — but all this can become less important when in any case you implement harsh control measures like a full lockdown.
Curious to see how the UK is doing? Here you go:
The issue with very limited testing capabilities in the UK has been debated for quite some time, and apparently being addressed by the government now. The inevitable consequence is that only people who show serious symptoms and need to be hospitalized (and not even all of them!) are tested. This will then result in a higher mortality rate as only serious cases are found. The mortality rate using the number of confirmed cases from 8 to 10 days before has been hovering around 20 to 30%. This is where the North of Italy was by mid March. In full emergency, overwhelmed and in reactive mode.
3. Number of patients in intensive care
Over the last 3 days Italy have also recorded an even more important signal from the statistics: the number of patients in intensive care at any point in time, after a non-stop and dramatic increase to over 4,000, has started to reduce. These are the patients in critical conditions and with the highest probability to succumb to the virus. This reduction should further anticipate a reduction in expected deaths. A marked reduction in this figure would also mean that hospitals may not have to take tough decisions on which people with severe symptoms can get access to life saving intensive care equipment.
4. Number of fully recovered patients
An additional element can be extracted from the number of people who made a full recovery. As of 6 April, this number is just under 23,000. We can see that this number is matching pretty much the total number of confirmed cases, minus deaths, with an 18–19 day delay. So it seems that on average, for patients who make a full recovery, it takes less than 3 weeks from testing positive to be fully confirmed negative.
Having taken into consideration the expected mortality rate (which seems to materialise with a delay of 8–10 days from new confirmed cases) we can expect the number of full recoveries to increase over the next 2–3 weeks, following the large number of new positive cases recorded in mid to late March, and it could reach a rate of 2,000–3,000 or more per day.
If this is the case, over the course of the next 2–3 weeks, Italy could finally get to a point where the number of confirmed infected/positive people at any point in time, actually decreases (the net number of new cases minus deaths and minus people who make recovery on a given day). This would be a great milestone, and a clear sign that we are on the right path.
Let’s hope so!
