Vaccination to create immunity against infectious diseases has been a key public health initiative since the mid-19th century. Children have been the main focus.
Smallpox was the only disease preventable by vaccination until the early 20th century. A vaccine for diphtheria was available from 1922, for tuberculosis from 1949 and for poliomyelitis (polio) from 1956. A wider range of vaccines, some combined for different diseases (such as the diphtheria–tetanus–whooping-cough vaccine), were available from the 1960s.
Though child vaccination against smallpox was compulsory between 1863 and 1920 (with a brief period of non-compulsion in 1872) almost all parents ignored this law – in 1916 fewer than 1% of babies were vaccinated.
Spanner in the works
Edgar Wilkins, the first director of school hygiene at the Department of Public Health, was firmly opposed to immunisation. His appointment was an odd choice, given that the School Medical Service was responsible for promoting immunisation. Child immunisation rates increased after Wilkins resigned in 1923. The second minister of public health, George Fowlds, was also a critic of immunisation.
Immunisation rates increased slowly. In the mid-1920s around 15% of schoolchildren were vaccinated. This increased to about 33% in the late 1920s. In the 1950s a target rate of 70% for the diphtheria vaccine proved hard to reach.
Severe polio epidemics in the 1940s and 1950s resulted in high immunisation rates once vaccines were available – 97% of children received the first dose and 93% the second dose of the oral vaccine in 1962. Rates dropped once polio was eliminated from New Zealand.
From the 1970s the decline of infectious disease as a cause of illness and death meant parents were less concerned about immunising children. Full immunisation rates were below 80% in many health districts in the mid-1980s. While this was historically high, it was below the 90% experts said was required for community immunity. In the early 21st century New Zealand’s full immunisation rates were lower than most other developed countries, and below a target rate of 95% of all two-year-old children.
In 2018 the national immunisation schedule covered the following diseases: rotavirus, diphtheria, tetanus, whooping cough, polio, hepatitis B, haemophilus influenza type B, pneumococcal disease, measles, mumps, rubella and human papillomavirus (girls only). Fully immunised boys received a total of 12 vaccinations, and girls 13. Protection against some of the diseases were combined in a single vaccine, which reduced the number of jabs. The schedule is reviewed every two years.
From its inception in 1907 Plunket emphasised infant nutrition. Once the School Dental Service was established in 1919 and the Department of Public Health assumed responsibility for the School Medical Service in 1921, close attention was also paid to child nutrition. From 1937 to 1967 free milk for schoolchildren was the department’s key nutritional initiative.
The appointment of a nutritional officer (Dr Muriel Bell) by the department in 1940 signalled a broader focus on the nutritional health of the whole population. Bell had researched the eating habits of workers and Māori communities for the Medical Research Council in the late 1930s.
Other initiatives included banning the sale of unpasteurised raw milk in 1953 and investigating links between cholesterol and heart disease in the 1950s. Emphasis on increased consumption of fruit and vegetables, and less sugar, fat and meat, was ongoing.
Despite a long history of publicity about good nutrition, unhealthy diets were a major cause of chronic disease in the 21st century. Obesity in children and adults increased from the late 20th century, with Māori and Pacific communities particularly affected.
In response, the Ministry of Health implemented healthy eating and physical-activity programmes such as the 2004 Healthy Eating – Healthy Action. Oranga Kai – Oranga Pumau strategy. This was discontinued by the National government elected in 2008, which also scrapped a mandate to schools about the sale of healthy foods. In 2015 the same government introduced the New Zealand Childhood Obesity Programme, which was criticised by many public health practitioners for focusing on individual behaviours rather than evidence-based population interventions to promote a healthy food environment and support healthy nutritional choices.
Hygiene and morality
From the 1920s schoolchildren participated in a daily ‘toothbrush drill’, which involved brushing, rinsing and spitting in group formation, overseen by a teacher. In 1921 School Medical Officer Dr Elizabeth Gunn inspected Stratford District High School and discovered that many of the boys masturbated on school grounds. She blamed the ‘listless, inattentive, and perverted’1 behaviour of the boys on the school’s failure to maintain the toothbrush drill.
Fluoride is added to some public water supplies to reduce dental decay. The Department of Health first conducted fluoride trials in Hastings in 1953. By 1978, 54% of New Zealand communities had fluoridated water; by 2016, the figure was 58%. Christchurch and New Plymouth were the only major cities without fluoridated water. A 2009 survey found that children living in fluoridated areas had 40% less severe tooth decay than children in unfluoridated areas.
Local councils made decisions about the fluoridation of drinking water until the Health (Fluoridation of Drinking Water) Amendment Act 2021 transferred this responsibility to district health boards.
Fluoridation illustrates how public health measures are often politicised and fiercely contested on ideological and philosophical grounds. Some people have argued that fluoridation of water supplies breaches individual rights and limits choices. In 1980 the Human Rights Commission ruled that it did not contravene human rights. In the 2010s there were further legal challenges to the fluoridation of water supplies. Consumer advocacy group, New Health New Zealand Inc., claimed in 2014 that fluoridation of water breached the right to refuse medical treatment under the Bill of Rights Act. They argued that fluoridation was a form of medical treatment that should not be compulsory. They also challenged the right of the South Taranaki District Council to add fluoride to the water supplies of Patea and Waverley. In 2018 these cases reached the Supreme Court, where a majority of judges, sometimes for different reasons, dismissed them.
Lifestyle and behaviour or commercially-driven epidemics
In the early 1970s, as infectious diseases declined, attention turned to risk factors associated with rapidly increasing mortality rates from chronic diseases and some cancers, including smoking, poor diet and excessive consumption of alcohol. There were vigorous debates about the most effective ways to tackle these epidemics and whose responsibility it was to change personal behaviours – individuals, government, or the industries that produced and marketed unhealthy products.
Tobacco control is often seen as a public health success story, and New Zealand has been one of the global leaders in this field. People have generally accepted the need for government intervention and that the tobacco industry bears some responsibility for the ill-health and deaths caused by smoking. Māori community and public health leaders have ensured robust actions have been implemented.
While the Department of Health issued warnings about smoking and cancer in the 1950s, a focus on polio epidemics meant tobacco policy measures did not properly start until the 1960s. Cigarette advertisements were banned on television and radio in 1963, and on billboards and cinema screens in 1973. Health warnings on cigarette packets were introduced in 1974 and there were significant increases in tobacco taxes during the 1980s. The Smoke-free Environments Act 1990 restricted smoking in workplaces and public places. There have been subsequent tobacco control measures, including further tax increases, smoking bans in bars and restaurants, pictorial warnings on packets, and a ban on the display of cigarettes in shops.
In 2012 a Māori Affairs select committee enquiry into the tobacco industry saw the government adopt the goal of making New Zealand smoke-free by 2025; it was the second country in the world (after Finland) to adopt an 'endgame' goal for smoking.
Despite this activity smoking remains widespread (around 13% of people smoked daily in 2017/18), especially among Māori (32%).
Hard to ignore
From 2008, 30% of the front and 90% of the back of cigarette packets had to be covered by graphic health warnings. The warnings included pictures of rotting body parts and diseased lungs and hearts. Packets also had to include the logo and phone number of Quitline, a service that helped people stop smoking. Research demonstrated that graphic warnings on packets were the most effective way of showing smokers how dangerous their habit was. In 2017 the warnings were made larger and standardised packaging was introduced.
There has been less comprehensive action against other risk factors for chronic disease. Despite requests from public health advocates, very few population-based measures have been implemented to reduce the harm caused by poor diet and excessive alcohol consumption.
Cancer screening programmes
National cervical screening started in 1990, and breast screening in 1998. Cervical screening occurred partly in response to the Cartwright Inquiry (1987–88), which investigated the treatment of women with cervical abnormalities at National Women’s Hospital in Auckland. Breast cancer screening was introduced following robust evidence from randomised controlled trials that a screening programme could reduce deaths among women. Colorectal cancer screening has also been implemented in response to strong evidence that it will be successful and cost-effective.
Other proposed national screening programmes, such as prostate screening, have not been introduced. Public health practitioners have been prominent in discussions about new screening programmes due to their expertise in assessing evidence about their benefits, limitations, and cost-effectiveness.