A History of Vaccines – from Cowpox to Covid

Peter McNamara

It’s no secret that vaccinations have revolutionised global health. Arguably the single most life-saving innovation in the history of medicine, vaccines have eradicated smallpox, slashed child mortality rates, and prevented lifelong disabilities. Possibly lesser known, however, are the historic events and pioneers we can today thank for not only saving millions of lives each year, but for laying the foundations of future vaccine development – something that is front-of-mind as the world rushes to make a viable coronavirus vaccine.
Vaccines typically require years of research and testing before reaching the clinic, but in 2020, scientists embarked on a race to produce safe and effective coronavirus vaccines in record time. Historically, vaccines have been researched and developed with limited economic resources: in the last year, every developed country has been throwing everything they can behind the race to beat Covid. Researchers around the world are currently testing 64 vaccines in clinical trials on humans. 20 have reached the final stages, and a handful are fully approved and are already being administered.
While the vaccines should bring the pandemic under control in the long run, they will not arrest the current surge in Ireland. And so for the coming weeks and months, the best tools at our disposal are those – social distancing, good hygiene, and quarantine – that have already proved capable of keeping the disease in check.

Humanity Gets a Shot in the Arm

A vaccine is a biological preparation that provides immunity to a particular infectious disease. Created in a laboratory, this preparation is often made from weakened or killed forms of the disease microbe, its toxins, or one of its surface proteins. When administered, a vaccine stimulates the body’s immune system to recognise this weakened form of the disease as a threat, to destroy it, and with that to further recognise and destroy any of the microorganisms associated with that disease that it may encounter in the future.
It’s like picking a fight with someone with one hand tied behind their back. With a vaccine, our body trains itself to destroy a given disease by fighting that disease when it can’t defend itself.
Like the situation we face with Covid today, vaccinations were born of necessity. Inoculation was first theorised and tested in China as far back as 200BC, in response to the great terror of the day: smallpox. Considering what humanity has had to contend with in the past, we might consider ourselves lucky. Smallpox was a fierce disease, with a death rate of 30%. Further accounts from the 1500s describe smallpox inoculation as practiced then in China and India. That method involved grinding up smallpox scabs and blowing the matter into nostril. With that in mind, an injection might seem the less unpleasant method.
The practice, known as “variolation”, came into fashion in Europe in 1721, with the endorsement of English aristocrat Lady Mary Wortley Montagu. It soon met with public outcry, however, after it transpired 2-3% of people died after inoculation, and further smallpox outbreaks were triggered.
The next iteration of inoculation, which turned out to be much safer than variolation, originated from the observation that dairy farmers did not catch smallpox. The 18th Century English physician, Edward Jenner, hypothesised that prior infection with cowpox – a mild illness spread from cattle – might be responsible for the suspected protection against smallpox. And so he set to work on a series of experiments that are now considered the birth of immunology, vaccine therapy, and preventive health.
The earliest vaccination – the origin of the term coming from the Latin for cow (“vacca”) – was born. Jenner’s vaccination quickly became the major means of preventing smallpox around the world, even becoming mandatory in some countries.
Almost a century later, in 1885, the French biologist, Louis Pasteur, saved a nine-year-old boy’s life after he was bitten by a rabid dog, by injecting him with a weakened form of the rabies virus each day for 13 days. The boy never developed rabies and the treatment was heralded a success. Pasteur coined his therapy a “rabies vaccine”, expanding the meaning of cow-based vaccine beyond its origin.
The global influence of Louis Pasteur led to the expansion of the term vaccine to include a long list of treatments containing live, weakened or killed viruses, typically given in the form of an injection, to produce immunity against an infectious disease.
Scientific advances in the first half of the 20th Century led to an explosion of vaccines that protected against whooping cough (1914), diphtheria (1926), tetanus (1938), influenza (1945) and mumps (1948). Thanks to new manufacturing techniques, vaccine production could be scaled up by the late 1940s, setting global vaccination and disease eradication efforts in motion. Vaccines against polio (1955), measles (1963), rubella (1969) and other viruses were added to the list over the decades that followed, and worldwide vaccination rates shot up dramatically thanks to successful global health campaigns. The world was announced smallpox-free in 1980, the first of many big vaccine success stories, but there was still a long way to go with other infectious diseases.
By the late 1990s, however, the progress of international immunisation programmes was stalling. Nearly 30 million children in developing countries were not fully immunised against deadly diseases, and many others weren’t immunised at all. The problem was that new vaccines were becoming available but developing countries simply could not afford them.
In response, the Bill and Melinda Gates Foundation and partners came together in 2000 to set up the Global Alliance for Vaccines and immunisation, now called Gavi, the Vaccine Alliance. The aim was to encourage manufacturers to lower vaccine prices for the poorest countries in return for long-term, high-volume and predictable demand from those countries. Since its launch, child deaths have halved, and 13 million deaths have been prevented.

Our Latest Creation: The Covid Vaccines

On November 9th, New York-based Pfizer and the German company BioNTech made history by presenting preliminary data indicating that their coronavirus vaccine was over 90% effective. It was the first time anyone had found such conclusive evidence. Following in the footsteps of Jenner and Pasteur, it looked like humanity had once again done away with yet another medical scourge.
BioNTech researchers began designing their vaccine last January when the “novel coronavirus” was first discovered. Through the summer and into the autumn, the world focused more and more of its attention on the Pfizer-BioNTech efforts, until the good news came. This vaccine requires 2 doses taken 3 weeks apart, and depends on freezer storage of –70°C.
In trials, the vaccine showed little difference in its protection of Black, Latino, and white volunteers; likewise, people with conditions such as obesity or diabetes enjoyed the same level of protection. The elderly also showed the same efficacy rate as people under 65. While this preparation caused no serious side effects, it frequently caused short-lived fatigue, fever, and muscle aches. These impressive results led rapidly to authorisations across the world. The European Union has since arranged to purchase 300 million doses. Pfizer and BioNTech expect to manufacture over 1.3 billion doses worldwide by the end of 2021.
Following hot on their heels is the Boston-based company Moderna. The Moderna vaccine is the second one authorised in America, coming a week after the vaccine made by Pfizer and BioNTech. Canada authorised the vaccine on December 23rd. In January, the European Union, Israel and the United Kingdom all granted it emergency authorisation.
Like Pfizer and BioNTech, Moderna began developing a vaccine for the coronavirus last January. Their preparation requires 2 doses, 4 weeks apart, and the vaccine is stored at –20°C. The United States government bankrolled Moderna’s efforts, providing nearly $1 billion in support. On November 25th, the company reached an agreement with the European Commission to supply up to 160 million doses. Moderna has made similar deals with other countries including Canada, Japan, Qatar and South Korea.
Another provider is the German-based, CureVac. In November, they negotiated a deal to provide the European Union with up to 225 million doses of their vaccine. They project manufacturing up to 300 million doses in 2021 and up to 600 million doses the following year. CureVac has collaborated with Elon Musk’s company Tesla on creating mRNA “micro-factories,” which could potentially be deployed around the world to make billions of doses of the vaccine.
Russia has also produced a vaccine, named Sputnik V. In November, Putin’s government began offering Sputnik V within the country in a mass vaccination campaign. But worry that the vaccine was rushed to approval led to widespread hesitancy in the country. Nonetheless, Putin has negotiated a number of deals to supply other countries with the Sputnik V vaccine, including Brazil, India, Mexico, and Venezuela.
In an unprecedented move in the coronavirus vaccine field, the group leading UK research efforts, Oxford-AstraZeneca, announced on December 11th that it would collaborate with the Russian creators of the Sputnik V vaccine, which is also made from adenoviruses, to see if a combination with Sputnik V might increase the efficacy of the Oxford vaccine. The trial is planned to take place in early 2021 in Ukraine. In August, the European Union reached an agreement for AstraZeneca to deliver 400 million doses if the trials yield positive results. The company has said their total annual manufacturing capacity for the vaccine, if approved, stands at two billion doses.
China has also been busy on producing a cure. Chinese company CanSino Biologics developed their vaccine Convidecia in partnership with the Institute of Biology at the country’s Academy of Military Medical Sciences. On Nov. 28, the Chief Executive of CanSino Biologics said in an interview that about 40,000 to 50,000 people had received Convidecia. Starting in August, CanSino began running effectiveness trials in a number of countries, including Pakistan, Russia, Mexico and Chile.

Vaccine Safety and Global Fairness

Vaccines are one of the great triumphs of modern medicine. They have helped add decades to human life expectancy and are one of the best tools for preventing disease and death. They do however require a measure of trust and confidence. Given that inoculation calls for the injection of a complex chemical preparation – which includes a small amount of a dangerous disease – it’s not surprising that many people are wary of vaccines and the effects they can have.
Vaccine scepticism has existed since Edward Jenner administered the first smallpox vaccine, in 1796. Reasons include religious beliefs, past medical exploitation inflicted on minority populations, and the current rampant misinformation on social media. And it has to be said the particularly rapid development and approval of Covid-19 vaccines is food for sceptics while offering a fertile breeding ground for conspiracy theories.
The truth is, vaccines are one of the safest medical interventions we have. Through the centuries they have done wonders for human health. But “safe” is not synonymous with “no side effects”. No medical treatment is completely free of side effects. So to expect the new range of Covid-19 vaccines to be free of them is unreasonable.
The risk of not being vaccinated against Covid-19 is far greater than the risk of side effects from the vaccine itself. Of the tens of thousands of people who have already been vaccinated, some have reported short-term symptoms like fever or aches. These are consistent with the brief side effects seen with all vaccines: local bruising at the injection site, headache, and a feeling of malaise.
Perhaps we should feel lucky we’ll be able to get one at all. Millions of people in poorer nations don’t have the comfort of knowing that huge deals have been struck with pharmaceutical companies on their behalf. That’s where Covax comes in.
Covax is a multilateral initiative aimed at ensuring that all countries have “fair and equitable access” to Covid-19 vaccines. Co-led by Gavi, the Vaccine Alliance (Gavi), the Coalition for Epidemic Preparedness Innovations (CEPI), and the World Health Organization (WHO), Covax is a voluntary arrangement that enables countries to pool their resources and risk by collectively investing in vaccine candidates while developing the political and logistical infrastructure needed for vaccine distribution.
Proportional allocation of vaccines through Covax is fairer and more efficient than an uncoordinated approach in which countries compete in the market to secure as much vaccine as possible for their own citizens.
The commitment to international cooperation embodied in Covax is critical to preventing a future dominated by “vaccine nationalism,” in which rich countries bid against each other to secure bilateral contracts with vaccine manufacturers and stockpile vaccine doses for their own citizens. Such vaccine hoarding by high income countries would be unfair because it would profoundly disadvantage people living in low income countries that lack the resources to procure vaccines for their citizens. And the irony is, it would also be ineffective, because it would fail to allocate vaccines to countries with the greatest need and greatest potential for harm reduction.
The fact is, no one on earth is safe from Covid until everyone is. We really are all in this together.