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Public health

by Kerryn Pollock

Public health initiatives have been at the forefront of improving health and life expectancy since the 19th century. The focus has shifted from quarantine and sewerage systems to vaccination and screening programmes, but the aim is still to prevent disease before it takes hold.

What is public health?

Public health means health and medical initiatives that focus on:

  • the prevention of disease
  • the promotion of good health
  • populations rather than individuals.

Public health professionals work in health protection and promotion rather than patient care in clinics and hospitals.

The substantial improvements in health since the 19th century have been largely attributed to public health initiatives and disease control rather than medical interventions – prevention has been more effective than cure.

The term ‘public health’ is sometimes used (by lay people) to describe health services that are funded by government through taxation – the public health system

Old and new models

The old or traditional model of public health was primarily concerned with sanitation and hygiene and, later, clean water and air. The new model, which arose in the late 20th century, added consideration of social, cultural and political factors as determinants of health, along with personal behaviour and lifestyle. In New Zealand, ethnicity is added to this list of factors.


The Ministry of Health oversees public health, a role enshrined in the Health Act 1956. This act also sets out local government’s public health powers and responsibilities. Local government’s role in public health was enhanced by the Local Government Act 2002. District health boards are required to promote and improve the health of communities under the Public Health and Disability Act 2000. Other government agencies (for example, those with social welfare, housing and transport responsibilities) also play a role in public health.

Managing public health

Early approaches

In the 19th century public health operated at a local level with a focus on disease control. This was addressed through quarantine measures, sanitary reform and vaccination.

Island isolation

Quarantine – an enforced period of isolation – was the first and earliest line of defence against infectious diseases in the 19th century. All people onboard ships affected by disease were quarantined on islands. This occurred less frequently later in the century as large, spacious steamships replaced sailing ships, and screening before departure improved. However, quarantining did not officially cease until 1943.

The Public Health Act 1872 set up a central board of health for each province and smaller local boards (which were usually the borough and city councils) within the provinces. After the provinces were abolished in 1876, one country-wide board controlled by central government was established, while local boards were retained. Both were poorly funded and were neither very active nor effective.

The Christchurch Drainage Board (1876–85) was one exception. It employed a full-time medical officer and was responsible for significant sanitation improvements, including the first sewerage system in New Zealand (completed in 1882). This led to a reduction in deaths from infectious diseases such as typhoid.


From the 1880s doctors advocated a central department of health, which government was also considering. The (ultimately unrealised) threat of a bubonic plague pandemic reaching New Zealand provided the impetus government needed to establish the Department of Public Health in 1900.

The department (from 1922 called the Department of Health, and from 1992 the Ministry of Health) was responsible for the identification of public health issues and the development of preventative and promotional public health services, which were delivered by regional offices. This remained the case until the late 20th century.


In the 1990s the government concentrated on financial efficiency and health services for individuals. Resources were directed away from public health. An independent Public Health Commission was established in 1993 to conduct research, develop policy and contract out public health programmes, but it was disbanded in 1996.

In the 2000s the government made public health a priority. The Ministry of Health planned and managed public health services – such as immunisation, tobacco control and mental health promotion – on a national level, but they were delivered by the regional district health board public health units or non-governmental organisations. The Public Health Advisory Committee was established in 2001 to provide independent advice to the minister of health.

Particular aspects of public health previously administered by the ministry became overseen by separate government agencies. The New Zealand Food Safety Authority was responsible for food safety and the Department of Labour for occupational health.

Local government

Water, waste and sanitation services remained key local-government public health responsibilities. Other functions that had an impact on public health included the provision of recreational facilities and public transport. The Local Government Act 2002 conferred on local government a new, broader statutory responsibility to ‘promote the social, economic, environmental and cultural well-being of communities’.

Pesky nuisances

The Public Health Act 1956 describes things that are offensive or potentially injurious to public health as ‘nuisances’. There are 17 separate nuisances. They are created, for example, ‘where any animal, or any carcass or part of a carcass, is so kept or allowed to remain as to be offensive or likely to be injurious to health’ or ‘where there exists on any land or premises any condition giving rise or capable of giving rise to the breeding of flies or mosquitoes or suitable for the breeding of other insects, or of mites or ticks, which are capable of causing or transmitting disease’.

Outside government

Plunket (originally the Society for the Promotion of the Health of Women and Children), which from 1907 provided public health services for infants and children under five, was the earliest non-government public health organisation. By the 2000s about 50% of the public health section of the overall health budget went to non-governmental organisations to deliver services to the community.

In the 21st century general practitioners and other health professionals who grouped together as primary health organisations (PHOs) had a mandate to improve and maintain the health of the population through the delivery of national public health services such as immunisation. PHOs also had a limited role in health promotion.

Tertiary-education institutions provided postgraduate training in public health, while university-based research was an essential source of information for the public health sector. The Public Health Association, a voluntary organisation, promoted public health and assisted in policy development.

Environmental health

Sanitation and water

In the 19th century poor public sanitation caused high death and illness rates from infectious diseases such as typhoid. Banning cesspits and installing sewers led to a reduction in these diseases.

Treatment of drinking water followed much later. Most communities drank water piped straight from a river or lake until chlorination was introduced from the 1950s.

Something in the water

Since the Second World War there have been two major disease outbreaks caused by contaminated water. In 1984 around 3,500 people in Queenstown became ill with gastroenteritis after a blocked sewer overflowed into a lake near the public water supply. In 2016 a campylobacter outbreak in Havelock North made over 5,000 people violently ill and was associated with three deaths. The disease was traced to a contaminated pond close to a bore from which drinking water was pumped.

Even in the early 2000s an estimated 500,000 people were drinking water that did not meet (voluntary) standards. New Zealand had higher rates of gastro-intestinal diseases than countries such as Australia, Canada and the UK – this was partially attributed to contaminated drinking water. The Health (Drinking Water) Amendment Act 2007 compelled public water suppliers to ensure water was safe.


The effect of poor and crowded housing on public health was recognised in the 19th century. Courts could declare buildings unfit for living purposes and councils could demolish unsafe or insanitary buildings, but these powers were rarely used – both were unwilling to interfere in the private housing market.

From the beginning of the 20th century flush toilets, sinks, baths, wash tubs and spouting became more common in the bigger towns and cities. Houses were larger and more weather-tight. The development of hydroelectricity meant hot water was instantly available for personal and domestic cleaning. Older houses and rental properties were not always so well-equipped, which contributed to the government decision to build state houses in 1906, and on a much larger scale from the late 1930s.

From 1935 councils had to conduct housing surveys. In Auckland these revealed significant overcrowding, particularly among Māori and Pacific Island families after the Second World War. Overcrowding was linked to high rates of illnesses such as tuberculosis. While overcrowding decreased from the 1960s, it increased in some areas such as South Auckland, and contributed to the epidemic of meningococcal disease in the 1990s and 2000s.

Insulation of new homes was not compulsory until 1977. By the early 2000s about half of all houses had only partial insulation and one-quarter had none. Cold houses affected health – New Zealand had higher winter mortality rates than northern European countries. From 1996 government insulation and heating subsidies were available for lower-income earners. In 2009 subsidies were extended to all pre-2000 houses.

The Building Act 1991 was less prescriptive than earlier building regulations, and allowed the use of untreated framing timber. In some dwellings the cladding was poorly weatherproofed, which caused building materials to deteriorate or rot. High levels of damp and mould in these houses were linked to ill health, particularly respiratory conditions such as asthma. Building regulations were subsequently strengthened and in 2017 the Healthy Homes Guarantee Act set up standards for rental homes that required them to be warm, dry and well-ventilated. From 1 July 2019 landlords signing any new tenancy agreement must have installed underfloor and ceiling insulation or provided a heating source that ensures the home is warm and dry. All rental accommodation has to meet these standards by 1 July 2021. Grants are available from government to assist landlords meet these requirements. 

Clean air

Air pollution, caused by industrial manufacturing and the burning of coal and waste, was a problem in towns and cities by the mid-19th century. It contributed to respiratory illnesses such as bronchitis and asthma.

From the early 20th century town-planning strategies separated industrial and residential areas, but did not reduce and manage pollution. Clean-air zones were first introduced in Christchurch in the 1960s. Government legislation led to maximum allowable pollution levels, increased monitoring and clean-air zones in some urban areas. Lead petrol for vehicles was phased out from the mid-1980s to the 1990s.

Air pollution remained a public health issue in the 21st century. A 2012 report found that air pollution was associated with 1,175 premature deaths, 607 extra hospital admissions for respiratory and heart illnesses, and 1.49 million restricted-activity days.


Smoke-free environments were a new focus from the 1980s. An anti-smoking public health campaign, the ‘Great Smokefree Week’, was held in 1986. Domestic airlines banned smoking in 1987.

Smoking room

Smoking in all indoor workplaces, including bars, and all indoor and outdoor areas at schools and early childhood centres, was banned in 2004. In 2011 prisons became smoke-free. Some councils discouraged smoking in outdoor public areas such as parks and playgrounds – South Taranaki District Council was the first in 2005.

After 1990 some indoor workplaces had special ventilated smoking rooms. These were banned in 2004, apart from in rest homes and care facilities, which were allowed to have smoking rooms for residents. However, employees and visitors could not use the room.

The Smoke-free Environments Act 1990 restricted indoor smoking. Employers had to provide smoke-free and designated smoking areas. Smoking was banned on passenger aircraft and restricted to certain areas on ships and trains, and in passenger lounges and restaurants. Smoking in bars was still permitted.

Healthy bodies


Vaccination to create immunity against infectious diseases has been a key public health initiative since the mid-19th century. Children were the main focus.

Smallpox was the only disease preventable by vaccination before the early 20th century. A vaccine for diphtheria was available from 1922, for tuberculosis from 1949 and 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 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 against smallpox.

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 of 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.

Immunisation schedule

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 would receive 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 was reviewed every two years.


From its inception in 1907 Plunket emphasised infant nutrition. When the School Dental Service was established in 1919, and after 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 providing 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 investigations into 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. In response, the Ministry of Health funded healthy eating and physical-activity programmes.

Hygiene and morality

From the 1920s school children participated in the 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 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. In 1978, 54% of New Zealand communities had fluoridated water; by 2016 it 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 areas without.

Local councils are responsible for decisions about the fluoridation of drinking water. In 2016 the Health (Fluoridation of Drinking Water) Amendment Bill was introduced which inserted the power for district health boards to make decisions and give directions about fluoridation of local government drinking water. In 2018 this Bill was still to come back to Parliament after the Select Committee process. Passage of this Bill would increase the powers of district health boards relative to local councils.

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. After decisions in the High Court and the Court of Appeal, their challenges to fluoridation went to the Supreme Court in 2018 where a majority of judges, sometimes for different reasons, dismissed these claims.

Lifestyle and behaviour

In the early 1970s, as infectious diseases declined, attention turned to lifestyle issues that caused ill health and death.

While the Department of Health issued warnings about smoking and cancer in the 1950s, a focus on polio epidemics meant tobacco control did not start until the 1960s. Cigarette advertisements were banned on television and radio in 1963, and on billboards and cinema screens in 1973.

Though tobacco-control initiatives (such as price increases) were associated with a decline in smoking rates, the long development period of lung cancer meant it was still the leading cause of cancer deaths in the 21st century.

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.

Campaigns against drink-driving started in the 1970s. However, the road toll remained high until the mid-1990s, when it declined rapidly. In the 21st century alcohol (along with speed) remained a major cause of road deaths.

Cancer screening programmes

National cervical screening started in 1990, and breast screening in 1998. Cervical screening occurred in response to the Cartwright Inquiry (1987–88), which investigated the treatment of women with cervical abnormalities at National Women’s Hospital in Auckland. While some have advocated for a free prostate cancer screening programme, screening of men without symptoms is not recommended by the Ministry of Health. A task force set up in 2012 to consider prostate screening concluded that while some men who would benefit from early diagnosis have limited opportunity to access appropriate health services, other men may suffer harms from over-diagnosis and overtreatment.

    • Quoted in Derek A. Dow, Safeguarding the public health: a history of the New Zealand Department of Health. Wellington: Victoria University Press, in association with the Ministry of Health and with the assistance of the Historical Branch, Department of Internal Affairs, 1995, p. 106. Back

Healthy minds

Mental illness is common in New Zealand. The first national survey on mental illness (published in 2006) found that 20% of New Zealanders experienced a mental disorder in a 12-month period, while 47% had at some stage in their life.

Mental health was traditionally separated from public health – and there were separate mental health and public health directorates at the Ministry of Health in the 21st century – but its prevalence in the population, and increasing policy and service emphasis on mental wellness and illness prevention, means it can be seen as a public health issue.

Mental wellness

Until the late 20th century mental health services and practitioners focused on treating mentally ill people. The rise of mental health self-help and advocacy groups from the 1970s contributed to a new focus on creating and preserving good mental health. In the 21st century government and health providers promoted mental wellness in addition to providing services for mentally ill people.

Social connectedness – the relationships people have within their families, workplaces and communities – was recognised as affecting mental health, particularly when connections broke down or were not present. This was regularly measured through surveys by the Ministry of Social Development using six indicators: telephone and internet access at home, contact with family and friends, contact between young people and parents, trust in others, loneliness, and voluntary work. The ministry’s planning and decisions were influence by trends in these indicators.

Income and loneliness

As with most health and well-being indicators, loneliness appears to have a relationship with socio-economic position. The 2008 Quality of Life Survey reported that loneliness rose as personal income dropped: 21% of people who earned $30,000 or less each year said they felt lonely sometimes in the past 12 months, compared with 7% of people earning over $100,000.

Ending discrimination

As a result of a general inquiry into mental health services in 1995–96, a major public health education programme to reduce discrimination against people with experience of mental illness was launched. The Like Minds, Like Mine campaign was prominent on television and radio.


Experience of mental illness is more prevalent and severe among Māori than other ethnic groups. Likely contributing factors include the low socio-economic position of many Māori, and the high proportion of young people in the Māori population. Māori also experience poorer health, more frequent hospitalisation and lower life expectancy than other groups.

Governments and health officials have tried to address this disparity by developing Māori mental health strategies and funding Māori-specific mental health services and providers.

Little was known about the prevalence of mental illness among Pacific Island people until 2006, when the first national survey of mental illness was published. This survey found that Pacific Island people had higher rates of mental illnesses than other ethnic groups apart from Māori. These findings contradicted previous beliefs that Pacific Island people had low levels of mental illness. In response, efforts were made to improve the Pacific mental health workforce and develop culturally specific services.

Suicide prevention

In the early 21st century approximately 500 people died from suicide each year, which was higher than road-accident deaths. This made suicide prevention a major public health concern. Strategic responses to suicide focused on youth (aged 15–24) until the New Zealand Suicide Prevention Strategy was released in 2006. This took an all-ages approach to suicide and recognised that suicide rates were relatively high in other age groups, particularly the mid-20s to mid-30s.

Social and ethnic inequalities


Health inequalities were a major public health concern in the 21st century. Low-income people have had consistently higher death and illness rates than those on higher incomes. They are more likely to engage in behaviours that have a negative impact on health, such as smoking and eating unhealthy food.

The situation is starker when ethnicity is considered. Māori are likely to be ill more frequently and die younger than non-Māori of the same socio-economic status – even those who do the same unhealthy activities. Pacific Island people experience higher death and illness rates than other ethnic groups apart from Māori.


Important studies on social inequalities in health were published from the early 1980s. One of the first investigated male mortality rates by occupational class. Men in higher occupational classes – professions such as medicine and law – had significantly lower death rates than men in lower occupational classes such as cleaning and labouring.

The New Zealand Deprivation Index, which measures deprivation by small areas or neighbourhoods, was developed in the 1990s. Census data was used to create a socio-economic scale from decile 1 (least deprived) to 10 (most deprived). This tool has conclusively shown that health inequalities exist on a continuum – the more deprived communities are, the higher the death and illness rates. This trend is repeated when examined by gender, age and ethnicity.

From 2005 the New Zealand Census Mortality Study linked census and death records. Researchers measured socio-economic position before death – this approach showed that low socio-economic status caused ill health, rather than the other way round.

Government responses

The economic reforms of the 1980s and 1990s were seen by some as increasing social inequalities in health. In the 2000s the government developed specific policies on inequalities in response to this. District health boards (established in 2001) had a statutory obligation to reduce inequalities. The Department of Health published a series of reports on this topic from 2002. Reducing inequalities was at the heart of many public health initiatives.

Concern about inequalities was not confined to the health sector. Because socio-economic position is determined by factors including employment, income and housing, a ‘whole of government’ approach was advocated. This meant that sectors such as social welfare, education and housing, as well as local government, were seen to have a role in reducing health inequalities.

Familiar themes

Statements made by health practitioners in the late 1960s and early 1970s about the health-status disparity between Māori and Pākehā would sound familiar to people living in the 21st century. In 1969 the New Zealand Medical Journal editor described Māori health as ‘our particular problem with underprivilege in the midst of plenty,’ and in 1972 wrote ‘nothing can conceal the unpalatable fact that for the most part the Maori is at much greater disadvantage healthwise than the European.’1

Māori health

The Māori population was devastated by new diseases brought to New Zealand by visitors and settlers, and declined for most of the 19th century. This, combined with significant land loss, set the scene for poor Māori health compared to other ethnicities into the 21st century.

In the 20th century improvements did occur in the wake of rising living standards and public health programmes that addressed particular illnesses such as tuberculosis. However, in the 21st century Māori still had higher death and disease rates than non-Māori.

A series of reports highlighting the disparities between Māori and non-Māori from the late 1950s contributed to the eventual rise of Māori health providers and culturally specific health programmes in the 1980s. The Department of Health started to support traditional Māori healers. By the early 21st century Māori health-provider groups contracted to district health boards, mainly based around tribal areas. It was hoped that treatment by Māori for Māori would reduce ethnic inequalities.

    • Quoted in Derek A. Dow, Safeguarding the public health: a history of the New Zealand Department of Health. Wellington: Victoria University Press in association with the Ministry of Health and with the assistance of the Historical Branch, Department of Internal Affairs, 1995, p. 200. Back

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How to cite this page: Kerryn Pollock, 'Public health', Te Ara - the Encyclopedia of New Zealand, (accessed 27 June 2019)

Story by Kerryn Pollock, published 5 May 2011, reviewed & revised 28 Nov 2018