We Examined the U.K.'s Flight Data to Predict Where The Mutant COVID Strain Likely Went
Public Health and Pandemics

We Examined the U.K.'s Flight Data to Predict Where The Mutant COVID Strain Likely Went

Andrew Eaddy
Clay Graubard
Andrew Eaddy, Clay Graubard
World Tracker: Where have the Mutated COVID Variants spread?
We are tracking which countries have detected the mutated coronavirus variants from the UK, South Africa, and Nigeria. View and download our data and see how accurate our prediction was.
Update

On Saturday, December 19, British Prime Minister Boris Johnson announced that a new strain of the coronavirus emerged in the country in late September, either on September 20th or 21st. According to early data presented by the New and Emerging Respiratory Virus Advisory Group (NERVTAG), a government committee of experts, the new mutant strain is anywhere from 39% to 93% more transmissible, with the average growth rate based on genomic data being 71% and the 95% confidence interval being 67% - 75%.

The new strain identified in the U.K. is similar to one identified in South Africa (they have have the same mutation at N501Y). However, the South African mutation has emerged independently from the British one according to Dr. Emma Hodcroft, co-developer of NextStrain.

Chart depicting the spread of SARS-CoV-2 S.N501 mutations (COVID-20)
Visualizing the new British (green) and South African (yellow) COVID strain growth (Source: NextStrain)

There is still a lot we do not know about the mutant British strain (the same is true with the South African too). We do not know if the new virus is deadlier or has a shorter incubation period, nor has the 71% increased transmissibility rate (the R0 of the virus) been confirmed.

However, there is a lot we do know. We know that the new mutant strain grew exponentially during the lockdown this fall, we know that vaccines are likely to work, we know that the new strain made up over 60% of new cases in London over the past week (which are up 40% week-over-week), and we know it accounted for “20% of viruses sequenced in Norfolk, 10% in Essex, and 3% in Suffolk.” (For context, the South African strain has accounted for 90% of the second wave cases.)

We also know that the mutated coronavirus from the U.K. spread to the Netherlands at least since early December. The strain has also been detected in Australia, Denmark, and now Italy (Rome, specifically).

  • Context: COVID first emerged in Wuhan, China around December 1, 2019. By January 24, 2020, the virus had spread to at least Thailand, Japan, South Korea, United States, Taiwan, Hong Kong, France, Vietnam, and Nepal.

In this article, Global Guessing will examine U.K. flight data from London Heathrow to predict where the new coronavirus strain might turn up. Based on our predictions, it is likely the new mutated strain is already in Europe, North America, Asia, and the Middle East. Note: We are only examining the spread of the British strain, not the South Africa one.

But beforehand, it is important to contextualize the significance of this new COVID strain, because there is a chance that we are about to face a COVID-20 threat greater than COVID-19's.

Contextualizing a +70% R0

As Clay wrote on Medium earlier this weekend, "if this new mutation of COVID-19 is 70% more transmissible—then the pandemic’s home-stretch will be a lot worse."

An R0 increase of 70% would make the coronavirus pandemic much worse for two reasons:

  1. An increase in the total number of cases
  2. An increased likelihood of hospital collapse

The first is fairly straightforward: Based on simple models developed early in the pandemic, a 70% increase in the R0 of the coronavirus (the number of people a single person, on average, will infect) would lead to a 70% increase in the total number of COVID-cases. Although we do not know if the lethality of the new strain is any different, if the case-fatality ratio (CFR) of the new virus were similar to the current strains the number of deaths would also increase by 70%.

  • Context: Had this new strain been the original, the U.S. would've crossed 550,000 deaths yesterday instead of 324,000.

However, the second point is the more worrying. Although developments in therapeutics and better care techniques have decreased the CFR of SARS-CoV-2, the disease caused by COVID-19, we know that as hospital capacity increases so too does the CFR. The increase in lethality is most drastic when the hospital system collapses.

We saw this early in the pandemic, when countries such as Italy, Sweden, Spain, and Iran saw their death-rates soar as their hospital systems collapsed.

Graph showing the CFR of multiple countries over time, including Italy, Sweden, Spain, and Iran. Data from OurWorldInData
Source: Our World In Data

Given that hospital systems both in the United States and across Europe are already strained, 70% more cases would likely tip hospital systems past collapse. Should this happen, per Clay's article on Medium, countries could witness over 8 times the number of deaths until they reach herd immunization from vaccination.  This is exactly the fear of an Italian health minister: "The mutation is probably already present in big cities, we risk the collapse of the healthcare system."

London Heathrow Flight Data

So where is this new COVID-20 strain heading?

Map showcasing which countries received the most flights originating from London Heathrow Airport 12/19-12/20
Destination of Flights from London Heathrow (Data Source: FlightRadar24)

Examining all out-bound flight data from London Heathrow Airport over the past 2 days–Saturday 12/19 and Sunday 12/20–we can get a sense of where the virus might have spread (data available for download at the end of article).

Over the past two days, there have been 463 flights out of Heathrow. The most common destinations (not including within the U.K.) were:

Destination Number of Flights
United States 56
Spain 25
Germany 24
U.A.E. 20
France 18
  • Context: Over the past two days, there were 17 flights to Italy (where the new strain has been detected).

There were also more than 10 flights (greater than the 9 to the Netherlands, where the new strain also is) to: Switzerland, Portugal, and Ireland.

Moreover, there are 16 more countries that had more 5 or more flights arrive from London Heathrow in the past 2 days (Denmark, which has the strain, received 5 flights in the past 2 days).

  • Note: We are only examining flight data from the largest international airport in London and only examining data from two days. Australia, which imported the new strain, only received one flight from Heathrow since Saturday. As such, this list is not exhaustive but illustrative. Moreover, we have also increased the time horizon and width of our confidence interval to account for these facts.

Predicting Where COVID-20 Goes

There is a 82.5% chance that at least 4 of following 5 countries identify the new COVID mutation from the U.K. within their borders in the next two weeks:

United States; Spain; Germany; United Arab Emirates; and France.

This prediction has an 89% confidence interval of [75%, 90%]. The key factors behind the probability were: The number of flights inbound from London Heathrow in comparison to Italy and each country's current COVID case count.

There is a 85% chance that at least 3 of the following 4 countries identify the new strain in the next two weeks:

India; Switzerland; Portugal; and Ireland.

This prediction has an 89% confidence interval of [75%, 90%]. The key factors behind the probability were: The number of flights inbound from London Heathrow in comparison to the Netherlands and each country's current COVID case count.

There is a 75% chance that at least 4 of the following 6 countries identify the new strain in the next three weeks:

Austria; Qatar; Sweden; Greece; Japan; and South Africa.

This prediction has an 89% confidence interval of [70%, 85%]. The key factors behind the probability were: The number of flights inbound from London Heathrow in comparison to Denmark, each country's current COVID case count, and the possibility of virus sequencing taking longer in the destination countries.

And there is a 73.5% chance that at least 4 of the following 10 countries identify the new strain within their borders in the next four weeks:

Canada; Egypt; Russia; Turkey; Hong Kong; Maldives; Nigeria; Poland; Romania; and Singapore.

This prediction has an 89% confidence interval of [60%, 80%]. The key factors behind the probability were: The number of flights inbound from London Heathrow in comparison to Denmark, each country's current COVID case count, and the possibility of virus sequencing taking longer or being delayed in the destination countries.

Detection of the virus critically depends on the amount of genomic sequencing done by each country on virus cases and is why we structured our time horizons the way we did:

Most Likely Entry Points

Map showcasing the cities where flights from London Heathrow Airport arrived. Indicating possible places where COVID-20 may be.
Destination of London Heathrow Flights, 12/19-12/20, 78% of data depicted.

Based on our flight data, here are the cities where the COVID-20 virus is most likely to be found:

Destination Number of Flights
Dubai 15
New York 13
Dublin 11
Madrid 10
Geneva 10
Paris 9
Amsterdam 9
Lisbon 9
Chicago 9
Doha 8
Athens 7
Stockholm 7

What's Next

The information that comes out in the next two weeks will be critical as there are still many unanswered questions regarding this new virus strain such as:

  • How much more transmissible is the new virus in actuality?
  • Is the new virus more deadly than the current strain? Is it less so?
  • Is the incubation period, asymptomatic rate, or hospitalization rate different?
  • Where has the new virus been detected?
  • In countries where it has been detected, what percentage of cases does it now make up? (Does it follow the pattern of the U.K. and South Africa where it quickly become dominant?)
  • What happens to the South African strain?

We'll be following the development of these new COVID strains, what might become the COVID-20 crisis, and the potential implications of this new strain on Brexit and the Global Economy in the coming weeks.

  1. Brexit: The emergence of a new virus strain comes at an unfortunate time for the United Kingdom as the deadline for a "hard-Brexit" is fast-approaching. The effect that this viral emergence will have on the negotiations and on the perceptions of the U.K. will be interesting, and is something we at Global Guessing will be keeping a close eye on.
  2. Economy: Although the news of vaccines and other major news have dominated the airwaves, should this new strain fall within the confines of the early analysis it will receive major attention because the implications this strain will have on public health. If the early analysis is right and the mutated COVID-20 spread exponentially during lockdowns, harsher measures will have to be taken and we would expect, at minimum, much greater volatility in markets. In the past, greater market volatility has lead to an increase in investments in safe haven assets such as gold and Bitcoin, given their functions as stores of value. We will be observing the movement of those assets closely, should this virus prove to be as problematic as early signs are indicating.

Our Data

Flights UK.xlsx - Google Drive
Flight Data from London Heathrow Airport, 12/19-12/20

Read Clay's Medium Post

Everyone Needs to Pay Attention to the British COVID Mutation.
Yesterday, U.K. Prime Minister Boris Johnson announced that a new strain of COVID-19 had emerged in the country late September which “might be as much as 70% more transmissible.” Today, the U.K…
Clay's post on Medium about COVID-20