The history of vaccination

The origins of vaccination

Vaccines have been in use for over 200 years, since the first ever vaccine was developed to protect against smallpox, a disease that killed up to half of all those infected and that took a major toll on human civilisation, in 1796. 

Before the development of the vaccine, people relied on a process called variolation – placing a small amount of viruses (contained in matter from smallpox sores) from recovering smallpox patients under the skin. Variolation was brought to Europe from Asia and Africa, where it had been in use for hundreds of years, but the process risked infecting the person with the disease it was meant to protect from. The development of a vaccine that was safer and more effective meant that people could be protected against smallpox without the threat of developing the disease.

The smallpox vaccine used material from a cowpox sore – a much less dangerous disease related to smallpox – to protect people against the disease without risking them developing smallpox. The smallpox vaccine was a live attenuated vaccine, which used a weaker version of a disease-causing germ/virus to immunise people against it.

It was not until the 20th century that a worldwide vaccination campaign led to the eradication of smallpox in 1980. Widespread vaccination meant that a disease that had killed hundreds of millions of people in the 20th century alone no longer poses a risk to human health and is no longer transmitted anywhere in the world. The last human case was detected in 1978. Smallpox is the first and only human disease to have been eradicated. 

A century of discovery

Following the development of the smallpox vaccine, scientists began to explore the possibility of using vaccination to protect against other diseases. Over the next hundred years, scientists developed methods to prevent rabies disease after contact with rabies using a similar method to that used for the smallpox vaccine. Scientists also successfully identified a strain of bacteria that causes diphtheria – a vital step in developing a vaccine for the disease. 

At the end of the 19th century, scientists discovered that bacteria killed with heat or chemicals in the lab could still make the immune system react. This saw the first inactivated vaccines be developed to protect people from infection with typhoid and cholera bacteria in 1896. 

Vaccination in the modern era

The 1918 Spanish Flu pandemic is thought to have killed up to 50 million people worldwide. During the pandemic, a great deal of research was done on producing a vaccine against influenza. However, due to a lack of understanding of the disease (for a long time it was thought to be caused by bacteria), it would not be until 1945 that a first vaccine against influenza was approved for use.  The vaccine successfully used inactivated influenza viruses that taught the body to fight the virus. While previous inactivated vaccines targeted bacteria, the influenza vaccine was the first inactivated vaccine that protected against a virus. Since then, an updated influenza vaccine has been produced every year to help protect communities from the disease. 

In the 1920s, scientists discovered that adding certain substances to vaccines could strengthen the body’s immune response safely. The discovery of adjuvants was a breakthrough and led to the first vaccine for whooping cough being strengthened with aluminium salts in 1932. Aluminium salts are still used as adjuvants in some modern vaccines.

The advances that led to a successful flu vaccine also led to scientists discovering a vaccine for polio, a disease that is thought to have killed over 2 million people in Europe  and caused life-altering disabilities in millions more before a vaccine led to its elimination in Europe. This inactivated vaccine was first administered in large numbers in 1954 in the United States. Today, the polio vaccine is included in childhood vaccination schedules across Europe, and across the world to ensure all children are protected. Mass vaccination campaigns led the European region to be declared polio-free in 2002. 

In 1963, a vaccine was developed against measles, another major cause of death and lifelong disability in Europe. Since then, as the vaccine was introduced in national vaccination schedules across Europe and throughout the world, the number of measles cases has dropped dramatically and the impact of the disease has been reduced significantly. Outbreaks still occur however, showing the importance of sustaining  vaccination efforts. 

A deepening understanding

As our understanding of our immune systems, diseases and genetics improved in the second half of the 20th century, scientists discovered new ways to help protect us from diseases. In the 1960s, scientists discovered the protein that enables the hepatitis B virus to cause disease. They used this discovery to develop the first protein-based vaccine that protects from a virus in 1981, which uses a small piece of the virus to teach the body how to fight off the disease.
In 1972, viral vector vaccines were successfully demonstrated in a lab for the first time, although it would be almost 50 years until a viral vector vaccine was approved for human use to prevent Ebola.  

In the 1960s, mRNA (messenger ribonucleic acid) was discovered for the first time. mRNA similarly to DNA is part of the coding system used to make proteins. Over the next few decades, scientists explored how mRNA could be used to prevent disease. It was not until decades later that an efficient method to deliver mRNA in the body was discovered. mRNA vaccines against influenza were tested in the 1990s, with potential rabies vaccines being tested in 2013. It was only during the COVID-19 pandemic that extra funding, unprecedented international collaboration, and renewed efforts led to the first mRNA vaccines being released. 

Foundation for the future

Vaccination as we know it today has existed for generations, significantly reducing the toll vaccine preventable diseases take on individuals, families and communities across the globe. We now have vaccines against many infectious diseases and the long history of scientific research and development has meant that lessons learned over more than 200 years continue to inform future development. 

 

1796 - The first ever vaccine

A live attenuated vaccine that uses matter from cowpox sores to protect people against the more dangerous smallpox.

1896 - The first inactivated vaccine

The first inactivated vaccines to protect people from typhoid and cholera are developed. 

1932 - First vaccine with adjuvants 

A vaccine for whooping cough becomes available. Following the discovery of adjuvants in the 1920s, it is the first vaccine to contain aluminium salts to boost the body’s immune response. 

1946 - The first influenza vaccine

The influenza vaccine was the first inactivated vaccine that protected against a virus. Since then, an annual influenza vaccine has been produced each year.

1952 - The first polio vaccine

Scientists discover a vaccine for polio, a disease that is thought to have killed over 2 million people in Europe and caused lifelong disabilities in millions more.

1961 - mRNA discovered

Scientists discover mRNA, opening a path to new kinds of vaccines.

1963 - First measles vaccine

A vaccine against measles, a leading cause of death and disability in Europe is discovered.

1972 - Viral vector vaccine breakthrough

Researchers successfully demonstrate the potential of using a harmless virus to deliver instructions to the body. 

1980 - Smallpox eradicated

A global vaccination drive leads to the eradication of smallpox, the only human disease ever eradicated. 

1981 - First protein-based vaccine

The first vaccine that uses parts of a virus is developed. 

2002 - Europe declared polio free 

Widespread polio vaccination puts an end to a disease that killed millions and left millions more with permanent disability. 

2006 - HPV vaccine 

A first vaccine is developed against HPV - a virus that can cause six types of cancer including cervical cancer and analcancer and is linked to tens of thousands of cancer cases in men and women across Europe each year. 

2019 - The first viral vector vaccine

A first vaccine that uses a harmless virus to deliver instructions to the body is approved to protect against Ebola more than 40 years after the concept was first demonstrated. 

2020 - The first mRNA vaccine

Almost 60 years after the discovery of mRNA and after decades of research, the first mRNA vaccine is made available to counter the COVID-19 pandemic.