COVID-19: This Is Why Europe Is So Concerned About The New Strain B.1.1.7.

For Europe, one year into this pandemic, with a new variant spreading and vaccine delivery delayed, things seem to have just gone from bad to worse.

This article provides an explanation of why the European Union is so afraid of the new strain B.1.1.7, which originated somewhere in Kent, England, and now has become the dominant strain in the United Kingdom.

From the very beginning of the pandemic, I explained in my interviews and columns that epidemiologists are most afraid of unpredictable mutations of the virus during a pandemic. In my very first interview, I emphasized that epidemiologists are even more afraid of mutations that allow the virus to spread more successfully and faster, than those that allow it to lead to the higher death rate in any infected person.

Virus strains that have acquired new mutations, which allow them to spread faster among humans, will have an advantage over previous strains. Through the process of natural selection, they will soon outnumber them. They will begin as very rare strains that develop in only a few individuals, but over time will become dominant at the level of the entire population.

On the other hand, mutations that make the virus more lethal to the host will not have any selective advantage, on the contrary. Such strains will be harder to spread to other people, than those that are less lethal.

However, it should be well understood here that infection-fatality rate (IFR) is a much weaker criterion for a natural selection of new virus strains than the rate of spread (i.e., basic reproduction number/rate, R0).

Therefore, some new mutation in the genome of the virus, which allows it to spread much more successfully from person to person, will lead to a very rapid proliferation of that specific strain. But what about the lethality of such selectively advantageous strain? Most often, it will be a matter of sheer luck or misfortune. The genes responsible for lethality will most often be elsewhere in the viral genome, i.e., they will be different from the genes that are most important for its transmission success (except in cases where both traits are somewhat related and conditioned by the same genes; then, such genes are said to show so-called “pleiotropic effects”).

But if we ignore cases of pleiotropy, the mutation(s) of a gene in the specific RNA molecule of the SARS-CoV-2 virus that allows the virus to spread faster will inevitably also cause the increase in the frequency of all other specific genetic variants on the same RNA molecule. Among them, there would be some other genetic variants, which are responsible for its “lethality” for the host. These are the variants found on exactly the same RNA of the same strain of the virus, i.e., like the mutation responsible for faster spread picked up “hitchhiking” genetic variants across that specific RNA (so-called “hitch-hiking effect”).

Thus, these “hitchhiking” genetic variants that are responsible for “lethality” of the virus may be unchanged from the previous, i.e. original strain of the virus; or they may also contain mutations. These mutations in another part of the viral genome could make the virus more or less dangerous for its host. These genes are most likely to be unaltered. They could also contain a “neutral” mutation, which doesn’t change the effect of the virus on its host’s health. They may also contain such mutations that will make the virus less dangerous for the host’s health than the previous strain was. So, it is quite unlikely that the same viral RNA that already mutated to make the virus more transmissible would also mutate at some other place to also make it more dangerous for human health.

That’s why I wrote in my previous article in the Medium that we would really have a lot of misfortune to find out that these new, mutated strains that spread faster — and thus cause us plenty of new problems — have also mutated to become more deadly for the carrier.

It is now very important to study this graph well. It was developed by Adam Kucharski from the London School of Hygiene and Tropical Medicine. The figure shows the expected number of deaths over 30 days for 3 different strains of SARS-CoV-2 virus. It represents a simplified, but a fairly realistic scenario in which the initial situation is 10,000 infected individuals, IFR is 0.8% and R0 is 1.1 (…I believe that, by now, most readers understand these parameters and realise that they are quite expected).

In such a situation, the gray strain starts with just under 100 deaths per day. Then, the dots in the graph are separated by periods of 6 days and show progression in time. After 30 days, this strain will be causing just over 100 deaths per day. The exact numbers don’t really matter, we’ll see why in the text just below.

Let’s look at the red strain now. It is spreading at the same rate as the original strain of the virus, but it has mutated so that it kills 50% more people, i.e. its IFR is 50% higher. Therefore, this strain kills just over 100 people a day on the first day, and 30 days later he reaches almost 200 deaths a day.

Finally, let’s take a good look at what to expect from the orange strain of the virus under these circumstances, which has the same death rate (IFR) as the original strain, but spreads 50% faster, i.e., its R0 is 50% higher? This strain will infect so many people in 30 days, that close to 1,000 deaths should be expected by the end of the final day. Compared to the original strain, this is about 8 times more deaths over the same period.

Now let’s just add that the variant originated from Kent in England, called B.1.1.7, could be considered a real “COVID 2.0” because it spreads about 50–60% faster than the original strain. That is the reason for the concern of the EU countries and the tendency of most governments to impose very strict closure measures. A few days ago, German Chancellor Angela Merkel mentioned for the first time that, in such new circumstances, Europe should even start thinking about a strategy of trying to eradicate the virus within national borders, because it is simply not possible to contain such strains in the long run.

Even the slightest mistake could lead to a huge increase in the numbers of those infected and dead. This would be a particular tragedy for all affected families, given that the vaccine is already available. Personally, back in March and April, I explained why it would be ideal to try to reduce the number of infected within national borders to a minimum wherever this is feasible. Countries that have resolutely embarked on this strategy to date have suffered the least damage both in health outcomes and economically. That is why Australia, New Zealand, Finland, Norway, Denmark, Iceland, began to adopt this strategy following the examples of Vietnam, Cambodia, South Korea, Singapore, China, Taiwan, and some other Asian countries.

Unfortunately, as if all of this wasn’t bad enough news already, we received another one a couple of days ago. Preliminary results from several research groups in the UK showed that not only B.1.1.7. virus strain spreads 50–60% faster than the original one. A caution was raised that we may have had so much misfortune that this strain is also about 30% more deadly than the original strain. I studied thoroughly the report of a group of UK Government’s experts called the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG). Although their preliminary analysis was based on a sample of only 8% of deaths that they could have taken into account, it is worrying that data from different groups in different places indicated an increased infection-fatality rate. The small size of their samples makes this result truly preliminary, but nevertheless, it should still be closely monitored.

The logical next question is: can the virus mutate even further, and thus avoid the immune response triggered by vaccination? In principle, even that is possible. But we have already had enough misfortune for the start of 2021 that it would be good if we could at least avoid that development.

Still, this pandemic has already become a real nightmare for epidemiologists. Whenever a light seemed to have appeared at the end of the tunnel, we would soon realise that those were the headlights of a new freight train heading towards us and which we needed to avoid, rather than the exit from the tunnel.

It is now a big challenge to decide on anti-epidemic measures during February and March 2021 — especially so for poorer European countries. Slovenia, as well as Bosnia and Herzegovina, are already practically the second and third most severely affected countries in the world by this pandemic when measured by the number of deaths per capita. Similarly, Northern Macedonia and Montenegro are within or very close to, the global top 10 most severely affected. My homeland Croatia, unfortunately, is not far away, either. We have an awkward combination of economic strength and age structure. Our economy is already hit very hard by this crisis, while the share of older, vulnerable and at-risk people in the total population is quite large.

If we leave the current anti-epidemic measures in force, this will be very bad for the economy. If we relax them to any extent, then we could welcome the spring of 2021 as one of the few hardest-hit countries in the world. Sadly, we are not far from that. In addition, if a new strain B.1.1.7. finds its way into Croatia, then even the existing measures could be insufficient.

It is very good that the numbers of those infected and hospitalized in Croatia are currently falling to manageable levels. However, due to everything mentioned in this text, we should be getting ready to face the most difficult period. During the first month of vaccination, we only had enough vaccines to vaccinate up to 2% of the population. Global demand is currently such that further deliveries by the main producers in the western world are delayed. The threshold for collective immunity is 70% for the original strain, but for B.1.1.7. it will be higher due to its more successful spread. Stopping the new strain will likely require more than 80% of people vaccinated, with a vaccine that is 95% effective, to reach collective immunity. At the same time, the vaccine is not licensed for children, and the results of the first research indicate that this new strain is spreading more efficiently among children than the original strain that started from Wuhan.

I wish the news was better, but that’s how things are looking today. What can be done? First, countries could vaccinate those over 70 years of age as soon as possible, so that they at least reduce the number of deaths if a new strain starts B.1.1.7. spreads within their borders. Second, they could improve border controls to delay the entry of a new strain for as long as possible. Third, they could start intensively monitoring the strains of the virus among all those who test positive, because if the strain is B.1.1.7. arrived, it is better to know it than not. Then, everything should be done to get all those infected and their contacts isolated, to buy more time for vaccination. But there seems to be a major problem with a vaccine delivery from U.S. companies that breaches the contracts that were signed. While the United States is now being prioritised for the delivery of the vaccines that are manufactured in that country and the same also applies for China and Russia — for Europe, one year into this pandemic, with a new variant spreading and vaccine delivery delayed, things seem to have just gone from bad to worse.


Declaration: Professor Igor Rudan, FRSE, is the President of the International Society of Global Health; co-Editor-in-Chief of the “Journal of Global Health”; Joint Director of the Centre for Global Health and the WHO Collaborating Centre at the University of Edinburgh, UK.

TWITTER: @ProfIgorRudan

FACEBOOK: Professor Igor Rudan



Image credit: Maria Teneva,; Graph credit: Assoc. Prof. Adam Kucharski, London School of Hygiene and Social Medicine, Twitter post;

Director of the Centre for Global Health and the WHO Collaborating Centre at the University of Edinburgh, UK; Editor-in-Chief, Journal of Global Health