The life-saving innovation of immunisation has faced suspicion and distrust ever since it was first devised, more than 200 years ago.

In 1798, Edward Jenner published his discovery that smallpox in humans can be prevented by exposing their bodies to the similar but less harmful cowpox. Jenner’s 1798 revelation of what is today known as vaccination (from vacca, the Latin word for cow), travelled quickly around the world. In 1800, cowpox vaccine was given in Constantinople. By 1801, more than 100,000 children in the United Kingdom were vaccinated. The following year, vaccinations started in Madras, India. In 1803 vaccines were administered in Puerto Rico; in 1804 in Mexico; and by 1805 children were already being vaccinated in Tasmania.

Governments and medical practitioners quickly understood the importance of Jenner’s discovery. The availability of a safe and easy-to-apply method to prevent smallpox, combined with state expansion both in Europe and across growing imperial domains, encouraged governments and health officials to attempt to actively protect entire populations from a dangerous disease. The early vaccination campaigns of the 19th century ended up being a milestone in the history of governmental involvement in healthcare provision, reshaping the way governments and populations relate to each other.

While scientists and medical practitioners were busy developing ways to store and transport the vaccine, governments and health officials were preoccupied with other challenges. Vaccines protect, first and foremost, the vaccinated individual, but a greater value perhaps lies in the protection they provide to society by reducing exposure and transmission. The success of a vaccination campaign depends on high vaccination rates in society, and achieving high vaccination rates, in turn, depends on understanding people’s motivations to vaccinate themselves or their children. Governments had to speak to these motivations to ensure public cooperation with their grand plans. They had to convince people that the vaccine would be beneficial for them personally and also appeal to their sense of solidarity and social responsibility.

With the first initiatives to vaccinate the population came the first waves of public resistance. Some were suspicious of a practice that was still new. For the most part, however, resistance was motivated by factors not directly related to the vaccines themselves. In the British colonies, where vaccination was incorporated into practices of colonisation and control, some Indigenous populations viewed the procedure – performed directly on the body – with understandable suspicion. The demand to instantly accept European medical practices as superior to local practice alienated many, as did the requirement to provide personal details to the authorities before the vaccine could be administered. In some European countries, vaccination as a practice, and vaccination campaigns as a policy, could be perceived as elitist. Revealing their distrust of state health agents, people alleged that the vaccine was ineffective or that it posed dangers hushed by the higher classes. Some parents protested compulsory vaccination, claiming that it violated their liberties to raise their children as they saw fit. For some people, this was essentially a political matter, not a medical one.

Governments gradually developed new methods for gaining the public’s trust and cooperation to replace mechanisms of enforcement and control. For over two centuries, health departments worldwide used newspapers, mass media, and community leaders to inform the public about the dangers of smallpox and other diseases and the benefits of vaccines. They have made vaccines free of charge and set up ad-hoc immunisation centres which operated in convenient locations and hours of operation. Governments have encouraged religious leaders to urge worshippers to vaccinate their children, and they have appointed special advisory committees, entrusting them with the double task of advising decision makers and reassuring the public about the safety and efficacy of vaccines.

Many common conceptions about healthcare and the state responsibility for its citizens’ welfare were shaped during these great vaccination campaigns. Before the 19th century, a unified public healthcare system, responsible for providing health services to the general population (or regulating the quality of such services), was not the norm. Often the provision of health services was dependent on a mixture of charitable, religious and other voluntary institutions that took care of the health needs of the impoverished. The notion that children are vulnerable members of society, who enjoy certain rights and protections, became more popular in the 18th and 19th centuries. Expectations from the state to provide health services as a way of defending these rights can be traced back to measures such as the Act to Extend the Practice of Vaccination 1840, which made vaccination free of charge for the poor in England and Wales. The Act to Further Extend and make Compulsory the Practice of Vaccination 1853 required that every child be vaccinated within three months of birth, at the expense of the state, by a doctor.

On May 8 1980, the World Health Organisation declared the world free of smallpox. The eradication of smallpox is considered a tremendous international public health achievement, and vaccination is largely accepted as one of the most significant medical innovations in the history of medicine. As we move forward with the largest immunisation campaign in Aotearoa – New Zealand history, we will possibly also be living through the latest shift in our understanding of healthcare provision and individual responsibility for the health of others.

The vaccination campaign directed against the Covid-19 virus underlines the importance of public cooperation in fighting the virus. Due to the appearance of new variants, achieving population immunity is dependent on very high immunisation rates. At the same time, the special characteristics of Covid-19 affect people’s motivations. Unlike smallpox or polio, Covid-19’s primary victims are (currently) not children, and it does not leave painfully visible signs on its survivors. Aotearoa New Zealand’s success in keeping the virus at bay made the threat of the disease seem remote to most New Zealanders. This means that it might not be fear or other self-interested motivation that will drive people to vaccination centres. This campaign is more reliant on social solidarity and a sense of moral responsibility. Its success might depend on increasing our individual sense of responsibility.

From the early days of the Covid-19 pandemic, New Zealand’s policy placed a strong focus on social solidarity. Waiting for the virus to “miraculously go away” or “learning to live with it” were never an option. Instead, the government chose to “go hard and go early” to protect all New Zealanders from the new disease and accompanied this policy with an empathetic language, urging the “team of five million” to unite against Covid-19. The New Zealand public, by and large, responded to this call during lockdowns and changing alert levels. As the immunisation campaign is about to enter its fourth and largest phase of vaccinating the general population, New Zealanders are required to step up once again. As we do, we will also be writing the latest chapter in the ongoing story of humanity’s fight against infectious diseases.