Basking in the afterglow of the initial COVID vaccine success is now holding us back

Without significant control of transmission, fragile vaccines cannot secure our future

Control, Eliminate, Eradicate are the three pillars of global disease reduction. These three powerful words are written through public health officials like a stick of rock. Under the auspices of public health, they have distinct meanings.

• ‘Control’ is defined as the deliberate action to reduce infection rates and hence the burden of disease.

• ‘Eliminate’ means reducing disease incidence to zero in a particular geographical area, but not necessarily worldwide.

• ‘Eradicate,’ the holy grail of disease management, is defined by WHO as the “permanent reduction to zero of the worldwide incidence of infection caused by a specific agent as a result of deliberate efforts.”

Control, eliminate and eradicate are synonymous with what ‘living with disease’ has always meant. If eradicate is not possible then control and eliminate are applied relentlessly through testing, monitoring, education, pharmaceutical interventions, and a huge range of social and environmental preventive measures. Sanitation, clean water and pasteurization are examples of control and elimination measures that enable many of us to live safely amongst hazardous pathogens we cannot eradicate from our environments.

None of these measures can be implemented effectively without global coordination, global health campaigns, political and economic support, and crucially, the setting of time defined targets. For example, the WHO is aiming to eliminate HIV/AIDS by 2030 - “...we now have the tools and knowledge to end the HIV/AIDS pandemic as a threat to public health — and to do so by 2030.”

With SARS-CoV-2 we have introduced a serious new global health threat to the world, paying little attention to control, eliminate and eradicate, and instead relying solely on vaccines for protection.

Successful vaccines

There is no doubt that the development of successful vaccines in modern medicine has made a significant contribution to keeping these three pillars standing tall and strong, saving countless lives. However, to be considered successful, a vaccine needs to be safe, highly effective, and in possession of the following three attributes:

• complete protection against infection for 90% or more of the population

• long-term protective immunity against infection (ranging from years to life-long)

• protection against severe disease if rare breakthrough infections occur.

A helpful feature when developing a vaccine is that the pathogen is antigenically stable, acquiring mutations very slowly. Boosters are then rarely required, if at all, after completing the initial primary vaccination series.

Successful vaccines include those developed for Smallpox, Hepatitis A, Tetanus and Diptheria, Measles, Mumps, Rubella (MMR) and the Human Papilloma Virus. When it comes to reducing disease burden, successful vaccines can do most of the heavy lifting for control, eliminate and eradicate. Measles was briefly eliminated from the UK in 2016 for example. Smallpox has been completely eradicated worldwide.

Partially effective vaccines

However, not all vaccines are born equal. ‘Partially effective’ or ‘imperfect’ vaccines - do not score so highly on these three attributes. ‘Partially effective’ is usually defined as providing less that 50% protection against infection, and/or protective immunity is relatively short-term. Their fragile nature means that they need to be used with care, and with a clear view of potential long-term consequences. Partially effective vaccines include those previously developed for HIV, malaria and dengue, although encouragingly, and after decades of hard work, there have been some welcome advances in the effectiveness of the malaria and dengue vaccines.

The development of a successful, durable HIV vaccine has proved particularly challenging. Some hope was provided with the RV144 vaccine and more recently the combination vaccine approach, but efficacy and durability for both approaches has now been deemed insufficient and these vaccines are no longer recommended for use in the wider community.

With SARS-CoV-2, the initial results of the vaccine trials gave rise to optimism that we had the makings of a successful vaccine delivered in record time. They were highly successful in that they offered good protection against severe disease, saving many lives, but it quickly became apparent that in terms of durable protection against infection, the vaccines underperformed. The presentation of the vaccines as offering ‘complete protection’ was a fatal sleight of hand that has hamstrung the entire pandemic response ever since. Poor protection against infection was not an unexpected possibility. As early as June 2020, prior to vaccine deployment, Dr Anthony Fauci claimed durability of protection was likely to be an issue:

“When you look at the history of coronaviruses…….., the reports in the literature are that the durability of immunity that’s protective ranges from three to six months to almost always less than a year. That’s not a lot of durability and protection.”

Dr Anthony Fauci

With little attempt to control transmission, these comments prove prescient, and over time, durability of protection has steadily declined. This has allowed rapid viral evolution and more transmissible novel immune-evading variants. The current crop of SARS-CoV-2 vaccines now provide negligible or no protection against infection and only modest protection against severe disease.

This disease continues to inflict social, economic and physiological havoc across the world. Increasing numbers of people are suffering with the devastating impacts of Long Covid, currently estimated to affect at least 65 million people globally. In the words of world-renowned COVID-19 researcher Dr. Zizad Al-Aly,

“The best way to prevent Long COVID is to prevent COVID in the first place. There is no Long Covid without COVID.”

But herein lies the problem.

With the current collective behaviour making it increasingly difficult to avoid infection, and most governments ignoring transmission control measures, the question arises: Could more regular boosters of these partially effective vaccines lead to better control of SARS-CoV2?

The logistics of boosters

Let’s imagine that a well meaning UK government decides to offer three vaccines every year to as many people as possible, in the hope that this will significantly suppress SARS-CoV-2 transmission and push the virus into an evolutionary cul-de-sac. With a total UK population of 67.33 million, a high uptake of 80% of the population would need 54 million people to accept a vaccine every four months. That’s 162 million jabs annually. With ~ 252 working days in a year, this would mean providing 643,000 jabs on each of these days, on a constant, ongoing basis. That’s the equivalent of vaccinating 1% of the population every single working day. Logistically, this would be a colossal challenge.

The UK’s record vaccination rate, set early in the pandemic, was 830,000 jabs in a single day. The daily average was well below this. Achieving this record necessitated 3,000 dedicated vaccination centres, mobilising 750 army personnel and recruiting tens of thousands of volunteers. It was a truly exceptional national effort. It is inconceivable that the perpetual logistical challenge of 643,000 daily jabs could be maintained, in purely practical terms. Even if this were possible, vaccine fatigue would quickly set in, with falling compliance rates quickly disrupting this strategy,

Dr Arijit Chakravarty’s group, whose previous modelling has been eerily accurate in forecasting the ongoing SARS-CoV-2 transmission dynamics, now predict that without serious efforts to quench transmission, even vaccinating the entire population multiple times a year will not be sufficient to prevent the emergence of novel, immune-evading variants. This is deeply concerning. Policy makers in most countries are fixated on controlling the virus through vaccination alone. More disturbingly, some countries have promoted infection as a benefit – an irresponsible, illogical and perverted interpretation of a ‘control’ measure, and an approach completely unprecedented for any other global health threat.

Many public health authorities and policy makers understandably want to focus their vaccination efforts more strongly on high risks groups, but as the proverb goes, ‘you’re only as strong as your weakest link’. High viral transmission in the wider community quickly leads to new immune evading variants, thus eroding the vaccine protection afforded to these vulnerable groups more rapidly. This is the unfortunate scenario we have today.

Protect the vaccine and perceptions of ‘NPIs’

‘Protect the vaccine’ was a concept promoted by Dr Deepti Gurdasani early on in the pandemic..

“Had vaccines been presented as one tool of many, with an additional focus on protecting vaccine efficacy by suppressing transmission to reduce the rate of evolution of variants, we may have done better.”

Dr Deepti Gurdsani

Protecting the vaccine was given little attention by governments, public health authorities or the public. Instead, we proceeded on the basis that we had deployed ‘perfect’ vaccines, a colossal strategic error. Alternatively, perceiving the vaccine as a valuable but fragile tool, in need of additional support, would have – and may yet – help us extract better value from whatever level of population vaccination we can realistically achieve.

A broader ‘vaccine plus’ strategy would include ‘non pharmaceutical interventions’ (NPIs). Unfortunately, this expression is a rather hapless description, as it is defines NPIs negatively – as not being something – thus creating an impression of inferiority.

To aggravate matters further, for many, NPIs have become firmly associated with restrictive social interventions, imposing individual obligations – masking, distancing, staying at home – rather than ‘enabling’ interventions, such as, air filtration, ventilation, far-UV sterilization and real time air sampling biosensors.

To quote Professor Brendan Crab AC, the CEO and director of the Burnet institute

“we need to pay close attention to passive controls, especially strategies to promote clean indoor air, and learn how to better engage at-risk communities, rather than focusing solely on active controls including testing, vaccines and treatments, crucial as they are."

Perhaps there were two principle reasons why, when SARS-CoV-2 engulfed the world, governments, public health officials and policy makers turned to the pharmaceutical industry for a solution. Firstly, the success of numerous existing vaccines gave hope to many. Secondly, the pharmaceutical industry is a well defined industry, with considerable lobbying influence. Trade associations, such as the Association of the British Pharmaceutical Industry and Pharmaceutical Research and Manufacturing of America provide clear lines of communication through industry representatives, thus helping to push the policy agenda.

In contrast, the collective ‘clean air’ design and engineering technologies are a multi-disciplinary, disparate group of professions, associations and institutes, spanning architecture and design, engineering, building trades, ventilation specialisms and more. While they each have their own trade associations, there is no overarching identity or unifying name for this sector to match the eminence of the pharmaceutical industry. Perhaps the ‘Safe Air Sector’ (SAS) could be a contender? [Motto - “Who breathes, wins”?]

Some critics of a ‘safe air’ approach claim that no single technology is 100% effective. While true, let us remember that engineering innovation accelerates at an unrivalled rate. For example, renewable energy technologies represent one of the fastest developing engineering sectors, with efficiency and energy generating capacity dramatically improving over very short time-scales.

This is far from unique in the world of engineering. In May 1961 JFK announced his ambition to put a man on the moon by the end of the decade; the astonishing pace of engineering capability meant that Neil Armstrong fulfilled that ambition just eight years later. That’s how fast technology can move when there is political will.

Safe air technologies will also continue to develop very rapidly. In contrast, vaccine development can be unpredictable, onerous and prolonged, due to the vagaries of pathogens and the complexity and heterogeneity of the human immune system.

This is not to say that an infection blocking, durable SARS-CoV-2 vaccine will not be forthcoming, but just as HIV, malaria and dengue have proved particularly challenging for vaccine developers, a successful and durable SARS-CoV-2 vaccine may also be hard to achieve.

Looking ahead

We currently remain basking in the afterglow of the initial vaccine success, but the sun is setting on the vaccine only strategy. By failing to quench transmission, we are steadily degrading the only tool we are using. Eradication of SARS-CoV-2 may never be possible, but control and elimination are certainly within our capabilities. A paradigm shift is urgently required to place ‘safe air’ technologies alongside pharmaceutical interventions as fundamental control measures. To achieve this, we need to elevate and unite engineered solutions so that they become a clearly identifiable sector to match the eminence and political heft of the pharmaceutical industry. We need to persuade leaders and policy makers that it is in all of our interests to apply such technologies.

Just as the earth’s climate did not pause while humanity dithered over whether global warming was real or not, SARS-CoV-2 will not wait for the WHO, public health officials and governments to vacillate and procrastinate over the current and long-term threat this virus presents. We need to use all the tools in the toolbox and rediscover what control, eliminate, eradicate really mean.