Which description best describes the focus of the public health nurse in the twenty first century?

Table of Contents Show

Why is primary health care important?
WHO response
Distribution
Determinants
Health-related states or events
Specified populations
Application
References (This Section)

About 930 million people worldwide are at risk of falling into poverty due to out-of-pocket health spending of 10% or more of their household budget.
Scaling up primary health care (PHC) interventions across low and middle-income countries could save 60 million lives and increase average life expectancy by 3.7 years by 2030.
Achieving the targets for PHC requires an additional investment of around US$ 200 to US$ 370 billion a year for a more comprehensive package of health services.
At the UN high level UHC meeting in 2019, countries committed to strengthening primary health care. WHO recommends that every country allocate or reallocate an additional 1% of GDP to PHC from government and external funding sources.

The concept of PHC has been repeatedly reinterpreted and redefined in the years since 1978, leading to confusion about the term and its practice. A clear and simple definition has been developed to facilitate the coordination of future PHC efforts at the global, national, and local levels and to guide their implementation:

"PHC is a whole-of-society approach to health that aims at ensuring the highest possible level of health and well-being and their equitable distribution by focusing on people’s needs and as early as possible along the continuum from health promotion and disease prevention to treatment, rehabilitation and palliative care, and as close as feasible to people’s everyday environment." WHO and UNICEF. A vision for primary health care in the 21st century: Towards UHC and the SDGs.

PHC entails three inter-related and synergistic components, including: comprehensive integrated health services that embrace primary care as well as public health goods and functions as central pieces; multi-sectoral policies and actions to address the upstream and wider determinants of health; and engaging and empowering individuals, families, and communities for increased social participation and enhanced self-care and self-reliance in health.

PHC is rooted in a commitment to social justice, equity, solidarity and participation. It is based on the recognition that the enjoyment of the highest attainable standard of health is one of the fundamental rights of every human being without distinction.

For universal health coverage (UHC) to be truly universal, a shift is needed from health systems designed around diseases and institutions towards health systems designed for people, with people. PHC requires governments at all levels to underscore the importance of action beyond the health sector in order to pursue a whole-of government approach to health, including health-in-all-policies, a strong focus on equity and interventions that encompass the entire life-course.

PHC addresses the broader determinants of health and focuses on the comprehensive and interrelated aspects of physical, mental and social health and wellbeing. It provides whole-person care for health needs throughout the lifespan, not just for a set of specific diseases. Primary health care ensures people receive quality comprehensive care - ranging from promotion and prevention to treatment, rehabilitation and palliative care - as close as feasible to people’s everyday environment.

Why is primary health care important?

Member States have committed to primary health care renewal and implementation as the cornerstone of a sustainable health system for UHC, health related Sustainable Development Goals (SDGs) and health security. PHC provides the 'programmatic engine' for UHC, the health-related SDGs and health security. This commitment has been codified and reiterated in the Declaration of Astana, the accompanying World Health Assembly Resolution 72/2, the 2019 Global Monitoring Report on UHC, and the United Nations General Assembly high-level meeting on UHC. UHC, the health-related SDGs and health security goals are ambitious but achievable. Progress must be urgently accelerated, and PHC provides the means to do so.

PHC is the most inclusive, equitable, cost-effective and efficient approach to enhance people’s physical and mental health, as well as social well-being. Evidence of wide-ranging impact of investment in PHC continues to grow around the world, particularly in times of crisis such as the COVID-19 pandemic.

Across the world, investments in PHC improve equity and access, health care performance, accountability of health systems, and health outcomes. While some of these factors are directly related to the health system and access to health services, the evidence is clear that a broad range of factors beyond health services play a critical role in shaping health and well-being. These include social protection, food systems, education, and environmental factors, among others.

PHC is also critical to make health systems more resilient to situations of crisis, more proactive in detecting early signs of epidemics and more prepared to act early in response to surges in demand for services. Although the evidence is still evolving there is widespread recognition that PHC is the “front door” of the health system and provides the foundation for the strengthening of the essential public health functions to confront public health crises such as COVID-19.

WHO response

WHO is helping countries to reorient their health systems towards PHC as a key means towards achieving UHC, SDG3 and health security. Health systems should be fit for people, fit for context and fit for purpose. Health system strengthening involves strengthening of health governance and financing; the health workforce; gender, equity and rights; information systems; quality and patient safety; maternal, newborn, child and adolescent health through to healthy ageing; sexual and reproductive health; medicines and medical supplies; emergency preparedness, response and recovery; work on communicable and non-communicable diseases, among others.

WHO has identified three strategic areas of work to strengthen PHC worldwide:

Providing a 'one-stop' mechanism for PHC implementation support to Member States, tailored to country context and priorities. This includes putting into action the Operational Framework for PHC and capitalizing on investment opportunities from the COVID-19 response, building back better PHC-based health systems during recovery efforts. This core function is driven by and builds on existing work and experiences from countries and regions from across the world.
Producing PHC-oriented evidence and innovation, with a sharper focus on people left behind. This work is based on existing implementation evidence, best practice guidance and implementation solutions, expertise from successful countries, and literature published to drive innovative solutions. Key deliverables include monitoring and measurement guidance to assess PHC progress in countries and, subsequently, a Global report on PHC progress, as well as an innovative capacity building effort as part of the WHO Academy.
Promoting PHC renewal through policy leadership, advocacy and strategic partnerships with governments, non-governmental organizations, civil society organizations, development partners, UN sister agencies, donors, and other stakeholders at global, regional and country levels. Among other initiatives, this workstream will establish an external Strategic Advisory Group on PHC to advise the WHO on PHC renewal worldwide, it will create a PHC award for recognizing PHC excellence globally, and it will promote new PHC partnerships and collaborative networks incorporating new stakeholders such as young health leaders, parliamentarians and civil society at large.

Students of journalism are taught that a good news story, whether it be about a bank robbery, dramatic rescue, or presidential candidate’s speech, must include the 5 W’s: what, who, where, when and why (sometimes cited as why/how). The 5 W’s are the essential components of a news story because if any of the five are missing, the story is incomplete.

The same is true in characterizing epidemiologic events, whether it be an outbreak of norovirus among cruise ship passengers or the use of mammograms to detect early breast cancer. The difference is that epidemiologists tend to use synonyms for the 5 W’s: diagnosis or health event (what), person (who), place (where), time (when), and causes, risk factors, and modes of transmission (why/how).

The word epidemiology comes from the Greek words epi, meaning on or upon, demos, meaning people, and logos, meaning the study of. In other words, the word epidemiology has its roots in the study of what befalls a population. Many definitions have been proposed, but the following definition captures the underlying principles and public health spirit of epidemiology:

Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems (1).

Key terms in this definition reflect some of the important principles of epidemiology.

Study

Epidemiology is a scientific discipline with sound methods of scientific inquiry at its foundation. Epidemiology is data-driven and relies on a systematic and unbiased approach to the collection, analysis, and interpretation of data. Basic epidemiologic methods tend to rely on careful observation and use of valid comparison groups to assess whether what was observed, such as the number of cases of disease in a particular area during a particular time period or the frequency of an exposure among persons with disease, differs from what might be expected. However, epidemiology also draws on methods from other scientific fields, including biostatistics and informatics, with biologic, economic, social, and behavioral sciences.

In fact, epidemiology is often described as the basic science of public health, and for good reason. First, epidemiology is a quantitative discipline that relies on a working knowledge of probability, statistics, and sound research methods. Second, epidemiology is a method of causal reasoning based on developing and testing hypotheses grounded in such scientific fields as biology, behavioral sciences, physics, and ergonomics to explain health-related behaviors, states, and events. However, epidemiology is not just a research activity but an integral component of public health, providing the foundation for directing practical and appropriate public health action based on this science and causal reasoning.(2)

Distribution

Epidemiology is concerned with the frequency and pattern of health events in a population:

Frequency refers not only to the number of health events such as the number of cases of meningitis or diabetes in a population, but also to the relationship of that number to the size of the population. The resulting rate allows epidemiologists to compare disease occurrence across different populations.

Pattern refers to the occurrence of health-related events by time, place, and person. Time patterns may be annual, seasonal, weekly, daily, hourly, weekday versus weekend, or any other breakdown of time that may influence disease or injury occurrence. Place patterns include geographic variation, urban/rural differences, and location of work sites or schools. Personal characteristics include demographic factors which may be related to risk of illness, injury, or disability such as age, sex, marital status, and socioeconomic status, as well as behaviors and environmental exposures.

Characterizing health events by time, place, and person are activities of descriptive epidemiology, discussed in more detail later in this lesson.

Determinants

Determinant: any factor, whether event, characteristic, or other definable entity, that brings about a change in a health condition or other defined characteristic.

Epidemiology is also used to search for determinants, which are the causes and other factors that influence the occurrence of disease and other health-related events. Epidemiologists assume that illness does not occur randomly in a population, but happens only when the right accumulation of risk factors or determinants exists in an individual. To search for these determinants, epidemiologists use analytic epidemiology or epidemiologic studies to provide the “Why” and “How” of such events. They assess whether groups with different rates of disease differ in their demographic characteristics, genetic or immunologic make-up, behaviors, environmental exposures, or other so-called potential risk factors. Ideally, the findings provide sufficient evidence to direct prompt and effective public health control and prevention measures.

Epidemiology was originally focused exclusively on epidemics of communicable diseases (3) but was subsequently expanded to address endemic communicable diseases and non-communicable infectious diseases. By the middle of the 20th Century, additional epidemiologic methods had been developed and applied to chronic diseases, injuries, birth defects, maternal-child health, occupational health, and environmental health. Then epidemiologists began to look at behaviors related to health and well-being, such as amount of exercise and seat belt use. Now, with the recent explosion in molecular methods, epidemiologists can make important strides in examining genetic markers of disease risk. Indeed, the term health-related states or events may be seen as anything that affects the well-being of a population. Nonetheless, many epidemiologists still use the term “disease” as shorthand for the wide range of health-related states and events that are studied.

Specified populations

Although epidemiologists and direct health-care providers (clinicians) are both concerned with occurrence and control of disease, they differ greatly in how they view “the patient.” The clinician is concerned about the health of an individual; the epidemiologist is concerned about the collective health of the people in a community or population. In other words, the clinician’s “patient” is the individual; the epidemiologist’s “patient” is the community. Therefore, the clinician and the epidemiologist have different responsibilities when faced with a person with illness. For example, when a patient with diarrheal disease presents, both are interested in establishing the correct diagnosis. However, while the clinician usually focuses on treating and caring for the individual, the epidemiologist focuses on identifying the exposure or source that caused the illness; the number of other persons who may have been similarly exposed; the potential for further spread in the community; and interventions to prevent additional cases or recurrences.

Application

Epidemiology is not just “the study of” health in a population; it also involves applying the knowledge gained by the studies to community-based practice. Like the practice of medicine, the practice of epidemiology is both a science and an art. To make the proper diagnosis and prescribe appropriate treatment for a patient, the clinician combines medical (scientific) knowledge with experience, clinical judgment, and understanding of the patient. Similarly, the epidemiologist uses the scientific methods of descriptive and analytic epidemiology as well as experience, epidemiologic judgment, and understanding of local conditions in “diagnosing” the health of a community and proposing appropriate, practical, and acceptable public health interventions to control and prevent disease in the community.

Summary

Epidemiology is the study (scientific, systematic, data-driven) of the distribution (frequency, pattern) and determinants (causes, risk factors) of health-related states and events (not just diseases) in specified populations (patient is community, individuals viewed collectively), and the application of (since epidemiology is a discipline within public health) this study to the control of health problems.

Below are three key terms taken from the definition of epidemiology, followed by a list of activities that an epidemiologist might perform. Match the term to the activity that best describes it. You should match only one term per activity.

Distribution
Determinants
Application

____ 1. Compare food histories between persons with Staphylococcus food poisoning and those without
____ 2. Compare frequency of brain cancer among anatomists with frequency in general population
____ 3. Mark on a map the residences of all children born with birth defects within 2 miles of a hazardous waste site
____ 4. Graph the number of cases of congenital syphilis by year for the country
____ 5. Recommend that close contacts of a child recently reported with meningococcal meningitis receive Rifampin
____ 6. Tabulate the frequency of clinical signs, symptoms, and laboratory findings among children with chickenpox in Cincinnati, Ohio

Check your answer.

References (This Section)

Last JM, editor. Dictionary of epidemiology. 4th ed. New York: Oxford University Press; 2001. p. 61.
Cates W. Epidemiology: Applying principles to clinical practice. Contemp Ob/Gyn 1982;20:147–61.
Greenwood M.Epidemics and crowd-diseases: an introduction to the study of epidemiology, Oxford University Press; 1935.