Public health

Public health is the science of keeping people healthy and stopping sickness. It helps groups of people stay well, from small neighborhoods to the whole world during a pandemic. Public health looks at what keeps people healthy and what might make them sick, thinking about many parts of life like feelings and friends.

This field mixes many areas of work. It studies how diseases spread, looks at numbers about health, and learns how society affects health. It also keeps the environment clean, helps communities stay healthy, encourages good choices, and makes sure everyone can get medical care when needed.

Public health has always been important. As cities grew, leaders made ways to keep people safe from diseases and bad conditions. For example, in Great Britain in the 1800s, new sewer systems were built to keep water clean and stop infections. These efforts help protect people and make life better for everyone.

Definition

Public health helps stop sickness, lets people live longer, and makes life better. It is done by working together and making smart choices. People, groups, towns, and cities all help.

The word public can mean just a few people or a whole city. Health means feeling good in your body, mind, and with others.

Public health is connected to global health. Global health looks at health for everyone around the world. Public health is different from public healthcare, which is health care paid for by the government.

Purpose

The goal of public health is to stop diseases, injuries, and health problems before they happen. We want to help people and groups stay healthy and live longer. Public health makes life better and safer for everyone.

Components

Public health is a big topic with many different areas and practices. It brings together experts like disease researchers, data analysts, and health services management specialists.

Today, public health work needs teams of different professionals. These teams can include disease experts, data experts, health workers, nurses, doctors, and many others.

Public health work has changed over time and keeps changing. Some common activities in public health include teaching people to wash their hands, helping mothers breastfeed, giving vaccines, helping people quit smoking, teaching about healthy weights, and making sure healthcare is available to everyone.

Methods

Public health helps people stay healthy by watching for health problems and encouraging good habits, like eating right and staying active. It looks at what can make a group of people healthy or sick, and what dangers they might face.

Many sicknesses can be stopped with simple steps that don’t need medicine. For example, washing your hands with soap can stop many diseases from spreading. Treating a sickness or stopping a germ from spreading can also be important, especially during outbreaks or when food or water might be unsafe.

Public health works with different parts of the health care system, like doctors’ offices and hospitals. It also includes things like checking food safety and helping prevent diseases in other ways, even when people aren’t in a hospital or clinic.

Public health uses maps and location data to understand where health risks are greatest.

Ethics

Public health ethics is about balancing people’s personal rights with their right to be healthy. This can be difficult because different ideas about what is right can lead to different ideas about what public health should do.

Sometimes, public health efforts might focus too much on personal choices and not enough on helping everyone stay healthy. In the past, some health campaigns were seen as pushing certain behaviors too much, which made some people unhappy.

Priority areas

Original focal areas

When public health began in England in the 18th century, it focused on three main areas: clean water and proper waste removal, controlling sicknesses that spread easily, and using science to study health. Great Britain was an early leader in public health because more people were moving to cities, which created new health challenges.

Changing focal areas and expanding scope

As time went on, public health started to focus more on long-term health problems like cancer and heart disease. In many countries, efforts to reduce early deaths in babies have been very successful. In developing countries, helping mothers and children stay healthy is very important, especially when food is scarce and money is tight.

Public health also watches for diseases like HIV/AIDS, diabetes, and infections that spread through water or animals. Public health programs are working to help people eat better and move more to stay healthy. There is also a growing focus on making sure everyone has a fair chance to be healthy.

Organizations

The World Health Organization (WHO) is a group that helps countries work together to keep people healthy. It has helped get rid of some diseases and works on many health issues today.

Most countries have their own health departments to take care of health problems within their borders. In the United States, for example, there are health departments in every state and city, and there are also groups like the Centers for Disease Control and Prevention that help with health issues both in the country and around the world.

Public health programs

Governments know that public health programs are important for keeping people healthy. These programs help prevent diseases and make life better for everyone. Vaccines have helped stop many serious diseases.

The WHO says public health programs should lead, work with others, create good rules, and watch over health to make sure things are getting better.

Behavior change

Many health problems happen because of things people do. Learning about why people make certain choices can help change bad habits. For example, showing how smoking hurts others has helped reduce smoking in public places.

Applications in health care

Public health helps doctors understand what communities need. It looks at current health services, asks what people need, finds the best ways to help, and supports decisions about health care.

Conflicting aims

Some health programs can be hard to agree on. For example, some people think rules about smoking or programs to prevent certain diseases take away personal choice, while others believe these rules save lives by protecting both individuals and the community. This shows the balance between keeping people healthy and letting people make their own choices.

Global perspectives

There are big differences in health care and public health services between richer and poorer countries. In many poorer countries, they don’t have enough trained health workers, money, or knowledge to give even basic medical care or prevent diseases. This often leads to many illnesses and deaths, especially because of extreme poverty. For example, some African countries spend less than $100 USD per person each year on health care, while the United States spends much more.

Many parts of the world still struggle with diseases that could be prevented or treated. As people live longer, poorer areas are also facing more long-term health problems along with infectious diseases. Good health for mothers and children is a big concern, made worse by not having enough to eat and living in poverty. The World Health Organization says that not feeding babies only breast milk for the first six months leads to many preventable child deaths each year. Giving medicine to prevent and treat malaria in pregnant women and young children is one way to improve public health in areas where malaria is common.

Since the 1980s, people have started looking at health from a bigger picture — not just what individuals do, but how things like money, education, and where people live affect health for whole groups. Health is influenced by many factors, including where people live, their income, education, and social connections. These are called social determinants of health. Poorer communities often have worse health, and even middle-class people may not be as healthy as those with more money. Public health today tries to create policies that help improve health for everyone fairly.

Health aid from wealthier countries is very important for many developing nations. After World War II, concerns about diseases spreading and events like the HIV/AIDS epidemic led to more health aid. From 1990 to 2010, health aid grew a lot. This aid comes from many places, such as private groups, foundations, and international organizations. Despite these debates, studies show that health aid can save lives, especially for young children.

The United Nations created the Sustainable Development Goals for 2030 to tackle health and other issues worldwide. These goals aim to reduce differences in health between countries, improve living conditions, and promote better health for everyone. Public health workers can use these goals to plan projects that help communities stay healthier.

History

Further information: History of water supply and sanitation

Until the 18th century

Since the start of human civilization, people have tried to stay healthy and avoid sickness. Different places had their own ideas about health based on what they believed and what they had around them. Even early societies cared about health, which is different from what some people thought before.

Public health didn’t start in Europe or because of the Industrial Revolution. Many ancient communities had ways to stay healthy. For example, in Southeast Asia, old medical practices and Buddhism taught ways to keep the body and mind balanced. In the Americas, people like the Mayans and Aztecs had markets with helpful plants. Aboriginal Australians used smart ways to keep water and food clean and safe.

Western Europe, Byzantine, and Islamicate societies also cared about staying healthy. They looked at things like weather, water, and food to keep people well. Leaders, soldiers, and religious groups made choices to protect their health, picking good places to live and changing habits when they moved.

In cities, leaders made rules to help everyone stay healthy. They kept roads and markets clean and made rules to reduce dirt and bad smells. Groups worked together to keep neighborhoods safe and healthy, and charities built places like wells and schools.

People also found ways to stay safe during hard times like wars, famine, floods, and big sicknesses. After the Black Death, some places started new rules like quarantine to keep others safe.

After the 18th century

When the Industrial Revolution began, cities grew fast and became crowded and dirty. This made sickness spread more easily. Places like London, Leeds, and Manchester grew very quickly, with poor living conditions.

The 1800s brought important changes. Edward Jenner started vaccination to fight smallpox. Doctors learned that giving sailors fruit helped prevent scurvy. Books and talks helped teach people about staying healthy.

In the 1840s, leaders in England started making rules to improve health in cities. The Public Health Act of 1848 helped make sure towns had clean water and good sewer systems. Later laws added rules about cleaning streets, giving out clean water, and keeping standing water away to stop mosquitoes.

In the United States, the first health department started in New York City in 1866.

The study of how diseases spread started with John Snow in 1854. He found that a dirty water well caused cholera in London by talking to people who got sick.

Scientists like Louis Pasteur and Robert Koch helped us understand and fight diseases. They found ways to stop germs and created vaccines. Others discovered how animals like mosquitoes spread sicknesses like malaria and yellow fever.

Society and culture

Education and training

People who want to work in public health can study at many places around the world, such as schools of public health, medical schools, or nursing schools. They learn important topics like how to count and study health problems, how health services work, and how to help people stay healthy. This learning usually needs a university degree.

All over the world, learning about public health has grown a lot in recent years. Groups like the World Health Organization and the World Bank help support this. They create plans to teach people the skills they need, making sure these plans fit what each country needs. Using technology can also help share health information with everyone, especially those who find it hard to understand health topics. It is very important for countries to know what skills they need and to build their own teams, instead of relying on help from other countries.

Schools of public health: a US perspective

In the United States, a report from 1915 helped start special schools for public health. These schools focus more on research than on everyday health work. Before this, public health learning was usually part of medical schools. The first school for public health opened at Tulane University in 1912, and more schools opened at places like Yale and Johns Hopkins in the following years. By 1999, there were 29 schools of public health in the US with thousands of students.

Over time, the kinds of students and what they learn have changed. At first, most students already had medical degrees. But by 1978, most students only had a bachelor's degree.

Degrees in public health

Main article: Professional degrees of public health

Schools of public health offer different kinds of degrees. Two main advanced degrees are the Master of Public Health (MPH) and the Master of Science in Public Health (MSPH). There are also doctoral degrees like the Doctor of Public Health (DrPH) and the Doctor of Philosophy (PhD).

The MPH and other professional degrees are for people who want to work in public health jobs, like in health departments or hospitals. The MPH can focus on understanding health problems and statistics, or it can include many different methods. The MSPH is more for people who want to do research and study.

For those interested in the science behind public health and wanting to do research or teach, there are academic degrees like the Master of Science, Doctor of Philosophy, or Doctor of Science. These degrees include more advanced studies and a big research project.

Notable people

• John Graunt (1620–1674) helped start the study of how diseases spread.
• Edward Jenner (1749–1823) made the first vaccine for smallpox.
• Benjamin Waterhouse (1753–1846) brought the smallpox vaccine to the United States.
• Lemuel Shattuck (1793–1859) was a big helper in improving public health in America.
• John Snow (1813–1858) is called the father of modern epidemiology.
• Sir Joseph William Bazalgette (1819–1891) built sewers in London to stop diseases like cholera.
• Louis Pasteur (1822–1895) did important research to help us understand and stop diseases.
• Robert Koch (1843–1910) proved that germs cause specific diseases, which helped save many lives.
• Charles V. Chapin (1856–1941) helped improve public health in the United States.
• Sara Josephine Baker (1873–1945) worked hard to improve health for children and mothers.
• Nora Wattie (1900–1994) improved health and cleaning in poor areas of Glasgow.
• Jonas Salk (1914–1995) made one of the first polio vaccines and pushed for people to get vaccinated.
• Ruth Huenemann (1910–2005) studied how to help children stay healthy by looking at what they eat and how active they are.
• Dilip Mahalanabis helped save many lives by using special drinks for people who were sick during hard times.

Country examples

Canada

In Canada, the Public Health Agency of Canada helps keep people healthy. It prepares for emergencies, fights diseases, and works on long-term health problems.

Cuba

Since 1959, Cuba has worked to improve health for everyone. The government makes sure all people can get medical care. Because of this, fewer babies die. Cuba also sends doctors to help other countries.

Colombia and Bolivia

In Latin America, public health has helped build stronger governments and included more people. In Colombia, it helped create ideas about equal rights. In Bolivia, similar changes happened after a revolution in 1952.

Ghana

Malaria is a big health problem in Ghana. It can be prevented and treated. Stopping mosquitoes and using medicine are important. Methods include screens on doors and windows, insect sprays, quick treatment when sick, and using nets treated with insecticide. These nets are sold and given out, but some people still don’t use them. New ways to watch for malaria use maps to find where help is needed most.

France

Mexico

United States

Public health programs in the United States began in the late 1800s. The country does not have one main system for paying for public health. Many different groups and programs handle it. Spending on public health grew but then went down, especially after a tough economic time. In 2012, experts said the United States spends too much on treating sick people and not enough on keeping people healthy. The COVID-19 pandemic showed problems in the public health system and helped people understand how important it is.

Taiwan

Taiwan has a strong public health system with its National Health Insurance, started in 1995, which covers almost everyone. The system is paid for by people, employers, and the government. Costs are kept low, so money is used well. During the COVID-19 pandemic, Taiwan did well by quickly starting checks at airports, tracking who might have been in touch with sick people, giving out masks, and keeping people informed through texts and social media. Taiwan also works on vaccines and taking care of people with long-term health problems.