Might vaccine dissenters be on to something?

Whoosh. That was the sound of Pandora’s box opening at the mention of this most polarising of topics. On the one (far) side are those that see all vaccinations as inherently evil.  On the other (far) side are some fairly mainstream personalities that liken vaccine refusal to drink driving.  

We all know the story: successful trials with wonderful results, developed at warp speed (US), restoration of a bit of national pride (UK); Covid essentially eliminated for the season. They demonstrably work – post vaccination, the levels of relevant antibodies created in vaccinated individuals boosts the humoral immune system to such an extent that Chris Whitty’s “wall of vaccinated people” should help prevent any future epidemic. 

Open and shut case? If you like simple answers it is probably best to stop reading here. The answer – as so often in life – is that a simple binary answer doesn’t adequately reflect the nuanced complexities. 

Let us take a very quick diversion into the maths. As per the British Medical Journal, the clinical trials were set up to succeed, and were “not designed to detect a reduction in any serious outcome such as hospitalisations, intensive care use, or deaths”. The various efficacies (relative risk reduction, or RRR) quoted for the various vaccines (all > 50 per cent and some in the 90s) are, as the name implies, relative values, which neglect to take into account the absolute risk reduction (ARR) across the whole population. 

Writing in the Lancet, Olliaro et al from the Centre for Tropical Medicine and Global Health at the University of Oxford make this point succinctly: “ARRs tend to be ignored because they give a much less impressive effect size than RRRs: 1.3% for the AstraZeneca-Oxford, 1.2% for the Moderna-NIH, 1.2% for the J&J, 0.93% for the Gamaleya, and 0.84% for the Pfizer-BioNTech vaccines”. In summary: relative efficacy (as reported in the popular press) is not the same as overall effectiveness.  

And herein lies the crux of the issue – the “risk of Covid” to an individual is hugely skewed by other factors, in particular by age, but also of course whether or not one has already had the disease (or indeed been exposed previously to it). What is good for the goose might not be so good for the gander.  Medical ethics – guided by the “first do no harm” principle – considers that the risk of any intervention (e.g. a Covid-19 vaccine) needs to be comprehensively lower than any risk of inaction, i.e. not being vaccinated. 

Consider three different subsets of possible vaccine candidates:

1.       An 80-year-old grandparent who does not think they have previously had Covid-19 decides to get vaccinated.  This is a rational course of action.

2.       My daughter – a child under 10 with no underlying health issues – is currently at essentially zero risk from Covid-19. It would take a lot to persuade me to allow her to be vaccinated with any of the above vaccines due to the precautionary principle: given zero risk of inaction, any risk of intervention is unacceptable. This is a rational approach, and is endorsed by the BMJ (Covid vaccines are “hard to justify right now for most children in most countries”) and by many medics, including this group of 40 UK doctors, citing short and long-term safety concerns, as well as a lack of demonstrable benefit to the overall community.

3.       I am 43; I have most certainly been exposed to the SARS-CoV-2 virus, and have previously exhibited all the symptoms of Covid-19. Given what we now know about natural immunity, the risk to me from further exposure to the virus (and any variants) is low. 

It is easy to imagine the decision-making process for potential vaccinees in categories (1) and (2) being relatively straightforward. But what about me? I would be delighted to take one for the team if it could be unequivocally shown that I was less likely to be a future burden on the NHS or a transmitter of the disease. But it seems perverse to take up a vaccination slot ahead of others (anywhere in the world) whose need is greater and who might wish to have one.

Where the benefits to the individual and the herd are not clear cut, the case in favour of the jab is weaker. The long-term effects are not – cannot – be known, and there are plenty of reports of adverse effects, which of course do burden both the NHS and the taxpayer (the vaccine manufacturers having been indemnified). There is also the potential of negative impacts on the herd: antibody-dependent enhancement (ADE) is a process whereby the presence of specific antibodies can be beneficial to a virus.  The trial data is silent on the matter of biodistribution, a greater understanding of which could help shed light on some of the possible adverse effects being noted. The much-vaunted “vaccine effect” in early 2021 celebrated by the UK media is not as unambiguous as it should be. One would expect the divergence of cases/admissions/deaths for vaccinated age groups to be in that order, but instead was the other way round: consistent with what one might have seen in a naturally ending epidemic. Then there is the unexplained phenomenon of increases in Covid-19 cases post-vaccination. Are we missing something?

But… “vaccines work”. Well yes, they do – but the question is at what cost, both to the individual, and the herd. We don’t know all the answers. The humoral immune system is not the only game in town, and the arguments against childhood vaccination do not instantaneously go away on an adult’s 18th birthday – life’s complexities invariably manifest themselves on a sliding scale. There is no point invoking the precautionary principle to encourage across-the-board vaccination now if there is even a sliver of doubt about the possibility of an “own goal” ADE-enhanced epidemic next winter. 

In the post-epidemic – virus-endemic – scenario we find ourselves in, “circulation of SARS-CoV-2 may in fact be desirable, as it is likely to lead to primary infection early in life when disease is mild, followed by booster re-exposures throughout adulthood as transmission blocking immunity wanes but disease blocking immunity remains high”, as per Lavine et al in the BMJ, who go on to state that “the marginal benefits should therefore be considered in the context of local healthcare resources, equitable distribution of vaccines globally, and a more nuanced understanding of the differences between vaccine and infection induced immunity”.

The science is nuanced. We should note that a group of doctors – including those who have actively promoted the safety of the Covid vaccines – not anti-vaxx cranks – have suggested that vaccination should be limited to those over 65 years of age plus any additional “at risk” categories.

In conclusion, and based on observed data to date, the argument in favour of universal vaccination – using the current crop of vaccines – is not unequivocal. 

The principle of informed consent exists for a reason, as it protects both the integrity of medicine and public confidence in it. Woe betides us if these go by the wayside.

Dr Alex Starling is an advisor to and non-executive director of various early-stage technology companiesFollow him on Twitter: @alexstarling77