Headline: Covid-19: What's at stake for the unvaccinated?

Hopes were high last Christmas that the pandemic would subside once a vaccine became available. Twelve months later, it’s obvious that this hope was premature. Roughly 20 percent of the German population have declined to be vaccinated. As the pandemic continues to take its toll, Germany is mired in a bitter debate about vaccines, vaccine mandates, and other containment measures.

Exactly why a not inconsiderable minority believes that vaccines pose a greater risk than the disease itself, and therefore refuse to be vaccinated, is puzzling to my colleagues in the field of risk governance and many others besides.

To illustrate the benefits of vaccines, let us consider the following thought experiment. Imagine that you were invited to play a game of Russian roulette with slightly modified rules. The Master of Ceremonies asks you to choose one of two variants:

• In the first, Variant A, the revolver is loaded with a single round, while the other five chambers remain empty.
• In the case of Variant B, the revolver is loaded with three rounds, while the other three chambers remain empty.

The MC also offers you this important piece of information: Namely, that they have randomly added a quantity of blanks or low impact rounds to the box of cartridges from which the revolver will be loaded. They explain that the box of rounds for a game of Variant A contains at least 30 times as many blanks and low-impact rounds as the box used to play a game of Variant B. In other words, if you choose to play Variant A, then you are three times less likely to be shot – whether lethally or with a blank round – than would occur if you opted to play Variant B. Likewise, choosing Variant A means that you are 30 times less likely to incur a severe injury or be killed.

All things considered, Variant A is clearly the safer option. Of course, in games of chance there are always outliers and the possibility of incurring a fatal injury can never be entirely excluded. Conversely, it is also possible that someone who chooses to play Variant B will beat the odds and survive – not everyone who chooses the second option will be fatally shot. But one thing is clear: anyone in their right mind who cares about their life would choose Variant A over Variant B – even though the risk of death remains.

What I have described in this thought experiment is playing out in the real world as the Covid-19 pandemic continues. The role of the MC is played by the SARS-CoV-2 virus, which sets in motion the two threat scenarios. Revolver A threatens those who are fully vaccinated; Revolver B threatens the unvaccinated. The only difference between Russian roulette and “virus roulette” is that you cannot escape the virus unless you are somehow able to completely isolate yourself for the foreseeable future – unfortunately, you can’t just opt out of a pandemic. Moreover, the odds of being infected by the virus are greater than the 1:6 chance of shooting yourself with a revolver. Around 6.42 million people have contracted the virus in Germany since March 2020. In other words, there was a 1:13 chance of contracting the virus during the pandemic in Germany to date. However, the longer the virus rages, the more people will be infected. This, in turn, worsens the ratio of infected to non-infected persons. But the odds are the same as they were in the thought experiment: Vaccinated people are roughly three times less likely than unvaccinated people to test positive for the coronavirus. In addition, vaccinated individuals are 30 times more likely to experience an asymptomatic or harmless infection.

In Germany, according to the Robert Koch Institute, 80.1 percent of people over the age of 18 years are fully vaccinated. In light of these sobering statistics, why have around 20 percent of the target population decided to remain unvaccinated? Considering the prospects for surviving this very real game of viral roulette, the reason cannot be that vaccines offer too little or no protection. Getting vaccinated also helps to keep other citizens safe: If you are better protected (and, as we saw, vaccination can shift the odds significantly in your favour), you are also less likely to pass on the revolver – i.e., vaccinated people are less likely to infect others than unvaccinated people (daily testing can further reduce the risk of infection for both groups). A study by the National Institute for Public Health and the Environment in the Netherlands concludes that fully immunized people who test positive for Sars-CoV-2 are 63 percent less likely to transmit the virus to members of their household than unvaccinated people who test positive for the virus.

Sceptics frequently point out that vaccines can have harmful side effects. Let’s consider this in the context of our experiment: Imagine, in the case of Variant A, that you had to climb a flight of stairs to pick up the revolver. It is quite possible that you could trip and break your leg in the process. There is even an exceedingly slim chance that you could have a very unfortunate fall and break your neck. Does this example downplay the risk of side effects? Not at all! The side effects of the approved vaccines are well known by now. As of 12 December 2021, some 3.3 billion people worldwide are fully vaccinated. Given the vast scale of this vaccination effort, it is almost impossible that an unusual or rare side effect has gone undetected.

National registers of adverse drug reactions are maintained worldwide and are particularly comprehensive in the Netherlands and the UK. The data from these registers reveal that about two serious reactions occur per 10,000 vaccinations. According to the Paul Ehrlich Institute, roughly 1,800 people in Germany have lost their lives due to side effects in the context of a campaign totalling 107 million vaccinations (first, second and third vaccinations). This corresponds to a rate of about 3 deaths per 100,000 vaccinated persons (57.8 million people in Germany are fully vaccinated). In comparison, Covid-related deaths in Germany (so far) total around 130 per 100,000 of population. To put it plainly: the probability of dying of Covid-19 is 40 times higher! Of course, the odds will vary depending on an individual’s age and medical history. But even in healthy young people, the likelihood of contracting Covid-19 and suffering serious consequences is much higher than the probability of experiencing a correspondingly serious side effect from a vaccine.

The objection that there are potentially unknown side effects that will only become apparent much later is also unfounded. On the one hand, the first signs of such side effects would already be apparent after one and a half years; on the other hand, long-term vaccine side effects that could remain unrecognized are extremely rare and are even less likely to occur with the new mRNA vaccine platforms than with conventional vaccines. The vaccine ingredients break down and are completely flushed out of the body within a matter of days or weeks. Returning to our flight of stairs and revolver: fatal falls account for around 10,000 deaths annually in Germany. It is not known how many of these deaths are due to falls occurring on stairs, but the figure undoubtedly exceeds the 1,800 deaths due to vaccine side effects.

No matter how you slice it, the statistics are unequivocal: Getting vaccinated will help to protect you and those around you – and if you choose to get vaccinated, you are highly unlikely to experience serious side effects. In short, there is no rational reason not to get vaccinated.