I remember posters urging us to keep it under our hats and telling us that walls had ears; we all knew that there were German spies about, ready to do us down, though I did wonder whether what I knew about the Home Guard could be of use to the enemy. However, I did not remember 'Keep calm and carry on', so I looked it up on Wikipedia and, as most of you will know, I found that it was a poster produced in 1938 but never widely circulated as the bombs started to fall. Nevertheless, to a large extent that was what those unsung heroines of the Second World War, our mothers, did. 'Make do and mend' is what they called it. And it is exactly what most people have been doing throughout this pandemic.
Adaptation and survival
Successful species, plant, animal and microbial survive by adaptation to their environment. Popularisation of scientific discoveries has led us to think of adaptation being a slow evolutionary process based on genetic mutations, but this is only part of the story. We humans have also learnt to adapt socially to our environment and, also, to change our environment to suit ourselves; this is a major reason for the success, the dominance of the human race on the planet. We have herded together, moved into cities, and taken control of plants and other animal species while increasing our numbers and territorial possessions. We fear only one species, ourselves, and (save only for mosquitos) we have become the most dangerous visible organism on Earth. But we have forgotten our biological vulnerability to the invisible.
This pandemic is a terrible and sad reminder of this biological truth. Microbes have always been mankind's greatest competitor, something we share with all other living organisms. We also depend on them for our health and nourishment and, indeed, we all have evolved from them. We need to continue to share the planet with them and for this we must adapt. The path of our environmental adaptation has relied on our resilience and our ingenuity as a species, and this is a large part of the story of medicine.
Our predecessors endured epidemics of plague, Black Death, cholera and typhoid fever. They also spread epidemics of smallpox, syphilis and influenza as their armies fought and colonised the world, generally attributing these diseases to physical contact or mysterious spread through air and water. Bacteria were first seen after the discovery of the microscope in the 17th century, but it was not until the work of Louis Pasteur in France and Robert Koch in Germany from 1860 that their role in spreading disease was recognised. Pasteur also showed that even smaller invisible particles, which he called viruses (the Latin for poisons), could cause diseases of plants and animals, and these were first seen in 1938 by Helmut Ruske, using his brother's new invention, the electron microscope.
As I wrote in an earlier essay (20 January 2021
), the coronavirus was discovered to be a cause of the common cold in David Tyrell's MRC unit in 1965, and it was here that the infectivity of these viruses by diffusion through air was demonstrated. All my advice on prevention in these essays has been based on this original insight. These historic studies of microorganisms have been followed by the extraordinary discoveries from molecular biology and chemistry that led to means of working out the molecular and genetic structure of viruses and of manufacturing vaccines using chemical replicas of their most dangerous antigens (3 February 2021
The four waves of COVID-19
This development of vaccines is a telling example of man's adaptive ingenuity in dealing with biological threats. Such ingenuity is essential to our survival as a species when microorganisms have such a biological advantage over us from their rapid genetic evolution, something that defeated Tyrell's unit in its search for a common cold vaccine and is amply demonstrated by SARS-CoV-2. The original virus arose from transfer from bats through another animal, still not identified, to a human in China, almost certainly from contact related to using it as food though there is a less likely possibility that it was in a laboratory accident. Popularly known as the Chinese virus, international travel relating first to the Chinese New Year and its high infectivity but low lethality, save to the elderly, ensured its rapid spread worldwide, causing the first wave.
Rapid spread, notably before symptoms developed, was an early finding suggestive of transmission as minute nanoparticles. This spread gave the virus its chance to evolve. Poor control in Britain, South Africa and Mexico led to newer and more transmissible variants appearing. Here in the UK, a second wave of the epidemic started when the first lockdown was lifted but public health measures failed. This resurgence allowed the Kent variant (now named alpha) to cause an obvious third wave superimposed on the second. Our third wave then initiated a second wave across Europe and India, where inevitable public health failure allowed a further variant, named delta, to develop. This one is somewhat less susceptible to the antibodies produced by vaccination or initial infection and poor control of our borders allowed it to come back to us to cause the fourth wave we are now experiencing.
Mankind versus virus
We must expect further variants requiring further vaccinations, and many of the measures we are still taking will continue to be necessary; no scientist or politician can reasonably be expected to tell us for how long. The best we can do is try to vaccinate the majority across the world, something that has only been achieved once before, for smallpox. It is a race we are unlikely to win. The pandemic so far has been a battle between the virus and humanity.
In a war, humanity needs both an attack and a defence. Our attack has been remarkable, both with drugs and vaccines, but our defence has been poor, relying on our resilience and our organisation; the latter, public health, has let us down. Ultimately, the race will almost certainly result in a draw as we achieve herd immunity through infection and vaccination but with the need for new vaccines, possibly antivirals, and stronger public health to keep the expected further viral variants at bay.
For the continuing battle, we need to be patient and as far as possible get on with our lives, adapting them to the environment as it changes around us. There will be some who write angry newspaper headlines and shout from the back benches, some who cheerfully have parties and crowd together (I noticed this at the G7 meeting), many who respond with despair to losses of loved ones and livelihoods, but also the majority, the phlegmatics, who will keep calm and carry on, behaving sensibly and helping others. They, perhaps you and I, are the infantry who hope to get back to a world as normal as possible, but a different and chastened world. Remember, the last time we in Europe endured such horrors, they lasted six years.
Anthony Seaton is Emeritus Professor of Environmental and Occupational Medicine at Aberdeen University and Senior Consultant to the Edinburgh Institute of Occupational Medicine. The views expressed are his own