Public health intervention

A public health intervention is any effort or policy that attempts to improve mental and physical health on a population level. Interventions involve social movements that strive to support public health at different levels of society.^[1] Public health interventions may be run by a variety of organizations, including governmental health departments and non-governmental organizations (NGOs). Interventions can be personal, community-level, national, and global. Common types of interventions include screening programs,^[2] vaccination,^[3] food and water supplementation, and health promotion. Common issues that are the subject of public health interventions include obesity,^[4] drug, tobacco, and alcohol use,^[5] and the spread of infectious disease, e.g. HIV.^[6] Health interventions are unique from public health interventions in their goals, approaches, and scope.^[1] The two are highly interconnected and necessarily complementary.

A policy may meet the criteria of a public health intervention if it prevents disease on both the individual and community level and has a positive impact on public health.^[7]

History

Public health emerged as societies conceptualized disease and created interventions.^[8] Interventions started as quantifying illnesses and analyzing efficacy of various approaches. Increased community life led to more need for organized health protection.^[8] Despite many countries having universal access to healthcare, existing social inequalities continue to impact equitable health. Inequality, war, and infectious diseases contribute to the need for public health interventions. These interventions have evolved to involve both public and private sectors, often working together to intervene in human rights issues related to health.^[8]

Types

Health interventions may be run by a variety of organizations, including health departments and private organizations. Such interventions can operate at various scales, but these interventions do not reach individuals simultaneously or to equal extent.^[1] The whole population can be reached via websites, audio/video messages and other mass media, or specific groups can be affected by administrative action, such as increasing the provision of healthy food at schools.^{[citation needed]}

Screening

Main article: Screening (medicine)

Screening refers to the practice of testing a set of individuals who meet a certain criteria (such as age, sex, or sexual activity) for a disease or disorder. Many forms of screening are public health interventions. For example, mothers are routinely screened for HIV and Hepatitis B during pregnancy. Detection during pregnancy can prevent maternal transmission of the disease during childbirth.^[9]

Vaccination

Main article: Vaccination schedule

Vaccination programs are one of the most effective and common types of public health interventions. Typically programs may be in the form of recommendations or run by governmental health departments or nationalised health care systems. For instance, in the U.S., the Center for Disease Control decides on a vaccination schedule,^[10] and most private health insurers cover these vaccinations. In the UK, the NHS both decides and implements vaccination protocols. NGOs also may be involved in funding or implementing vaccination programs; for instance Bill and Melinda Gates Foundation assists governments in Pakistan, Nigeria and Afghanistan with the administration of polio vaccination.^[11]

Supplementation

Supplementation of food or water of nutrients can reduce vitamin deficiency and other diseases. Supplementation may be required by law or voluntary. Some examples of interventions include:

• Iodised salt to prevent goitre.^[12]
• Folic acid in wheat flour to prevent spina bifida, a birth defect.^[13]
• Fluoridated water to prevent tooth decay.^[14]
• Vitamin D milk to prevent rickets.^[15]

Behavioural

Main article: Behavior change (public health)

Interventions intended to change the behaviour of individuals can be especially challenging. One such form is health promotion, where education and media may be used to promote healthy behaviours, such as eating healthy foods (to prevent obesity), using condoms (to prevent the transmission of STDs), or stopping open defecation in developing countries (see for example in India the campaign Swachh Bharat Mission).^{[citation needed]}

The use of laws to criminalise certain behaviours can also be considered a public health intervention, such as mandatory vaccination programs^[16][17] and criminalisation of HIV transmission.^[18][19][20] However, such measures are typically controversial, particularly in the case of HIV criminalisation where there is evidence it may be counter productive.^[18][19][20] Laws which tax certain unhealthy products may also be effective, although also not without controversy, and are sometimes called a "sin tax". Examples include the taxation of tobacco products in the U.S. and New Zealand,^[21] and sugared drinks in the UK.^[22]

Structural

Structural interventions locate the causes of public health issues, including social, political, and economic factors.^[23]These interventions consider the impact of culture and values on health. Structural changes strive to promote public health through altering social norms. This may involve organization and establishment interventions, including resource distribution and healthcare accessibility. Healthcare accessibility interventions focus on the unequal distributions of resources and power in bigger systems. This include improving socioeconomic inequities and efforts focused on improving the health of marginalized populations.^[23]

Impact

Health impacts can be sorted and displayed as a pyramid with five levels of intervention; the interventions at the base of the pyramid have the greatest population impact and require less individual effort; the higher tier interventions have the least population impact and require the most individual effort to prevent negative health outcomes and promote positive health outcomes:^[14]

• Level 5 Counselling and education
• Level 4 Clinical interventions
• Level 3 Long-lasting protective interventions
• Level 2 Changing the context to make individuals’ default decisions healthy
• Level 1 Socioeconomic factors: (poverty reduction, improved education

Evaluating efficacy

Evaluating and predicting the efficacy of a public health intervention, as well as calculating cost effectiveness, is essential. An intervention should ideally lower morbidity and mortality. Several systematic protocols exist to assist developing such interventions, such as Intervention Mapping.^[24]

See also

• WASH (water, sanitation, hygiene)