OPINION: Let’s be thankful, not sceptical, that a Covid-19 vaccine is here

The news that vaccines against the Covid-19 virus are making progress in testing is a fillip towards the end of a year dominated by the worldwide spread of this very infectious and nasty disease that has claimed the lives of over a million people in ten months. However this news has also been accompanied by scepticism about the vaccine development as the spread of an ‘anti-vaxxer’ attitude continues. Too much negativity and there is a danger that deadly diseases which vaccines have been successful against will start to spread again. It’s easy to take for granted that modern science provides an unprecedentedly positive background to our lives, health science in particular, and that vaccine science is one of the best representations of that keeping a multitude of people alive who once would have died at a young age.

The history of vaccine development is fascinating and there aren’t many better science stories than that of Edward Jenner, the 18th century physician in a Gloucestershire village who discovered the vaccine for smallpox and it has been estimated that as an individual his work has saved more lives than anyone else in history. He had noticed that milk maids working with cows developed an immunity to smallpox after contracting the less virulent cowpox.

He started to treat smallpox patients with doses of cowpox and found that it had positive results. He wrote it up in a paper and in 1798 his innovation was accepted and the practice began to spread.

Jenner’s great insight was that a similar but lesser form of a disease would trigger and build the bodily responses to recognise the actual disease and ward it off at an early stage and provide a level of immunity in the future. This has been the principle on which the science of vaccines has been working ever since. From Jenner the science of immunology grew and it was 100 years later that Louis Pasteur named them vaccines, the Latin word for cow, in tribute to Jenner. From there vaccines have been developed for other mass killers such as tetanus, measles, mumps, chicken pox, polio and influenza which are all at least restricted if not eliminated. The single biggest success story is smallpox which still claimed the lives of 300 million people in the 20th Century but which, due to a mass vaccination programme overseen around the world by the WHO, meant that by 1979 it was announced as no longer existent as a viral infection. There are now 25 diseases recognised by the WHO as preventable by vaccine and routine vaccinations now save millions of lives around the world every year.

I’ve always found the science of vaccines fascinating. It says much about the trade offs and compromises that evolution has left us over millions of years that our immune systems exaggerate what is needed to fight a small dose of a disease. Natural selection has retained exaggerated immune responses in its retention of things that help us survive. (Our irrational phobias are another example of this.) This natural response, the over-reaction of immune systems, has been put to work by vaccines that trigger an exaggerated response that then protects us in the future. It would be 150 years after Jenner when scientists discovered that

it was the generation of ‘antibody’ proteins within white blood cells which manifested as an immune response and moreover these antibodies could be produced with vaccines. Modern vaccines still consist of modified forms or killed micro-organisms taken from the original pathogen. In the case of the recent proposed Covid vaccine – a tiny sample of the RNA of the virus.

Finding the right amount of, and an effective strand of, the lesser disease, is a process of trial and error. Hence, alongside its development has also been a host of scientific demands for extensive testing, as much data as possible and peer reviewed scientific papers. Even when a vaccine comes along the scientific arms race between vaccine development and disease manifestation will continue as with flu, which often mutates, and vaccine developers may have an ongoing battle with coronavirus if it mutates. The extent of the ongoing challenge is shown by the fact that there are diseases for which a vaccine still proves elusive, notably malaria and HIV. There have been controversies about vaccine side effects but these have often been overblown, as with the MMR vaccine, which study after study has shown to be safe.

Like any medicine, some side effects are inevitable but these are vastly outweighed by the lives that have been saved and lived after vaccination.

We are extremely lucky to live in an era, afforded to us by restless and robust scientific research, when the majority of people live to see out a long and full life – much longer on average than our recent ancestors. Vaccines are probably the single greatest cause of this.

Stuart Hobday was the founder of Norwich Science Festival, is a PHD student in philosophy of science at UEA and author of Encounters with Harriet Martineau.