MODES OF PREVENTION

When an objective has been defined in preventing disease, the next step is to identify suitable and feasible methods of achieving it, or a strategy with tactical objectives. This determines the method of operation and the resources needed to carry it out. The methods of public health are categorized as health promotion and primary, secondary, and tertiary prevention.

Health Promotion
Health promotion is a guiding concept involving activities intended to enhance individual and community health and well-being. It seeks to increase involvement and control of the individual and the community in their own health. It acts to improve health and social welfare, and to reduce specific determinants of diseases and risk factors that adversely affect the health, well-being, and productive capacities of an individual or society, setting targets based on the size of the problem but also the feasibility of successful intervention, in a cost-effective way.
Health promotion is a key element of the New Public Health and is applicable in the community, the clinic or hospital, and in all other service settings. Some health promotion activities are government interventions such as mandating the use of seat belts in cars, requiring that children be immunized to come to school, declaring that certain basic foods must have essential mineral and vitamins added in order to prevent deficiency disorders in vulnerable population groups, and requiring that all newborns should be given prophylactic vitamin K to prevent hemorrhagic disease of the newborn. Setting food and drug standards, and raising taxes on cigarettes and alcohol to reduce their consumption, are also part of health promotion. Health promotion is practiced by persons with many professional backgrounds, working in many different organizational settings.
Raising awareness and informing people about health and lifestyle factors that might put them at risk requires teaching young people about the dangers of sexually transmitted diseases (STDs), smoking, and alcohol abuse to reduce risks associated with their social behavior. It might include disseminating information on healthy nutrition, for example, the need for folic acid supplements for womenin the age of fertility and multiple vitamins for the elderly. Community and peer group attitudes and standards affect individual behavior. Health promotion endeavors to create a climate of knowledge, attitudes, beliefs, and practices that are associated with better health outcomes.

Primary Prevention
Primary prevention refers to those activities that are undertaken to prevent the disease and injury from occurring. Primary prevention works with both the individual and the community. It may be directed at the host, to increase resistance to the agent (such as in immunization or cessation of smoking), or may be directed at environmental activities to reduce conditions favorable to the vector for a biological agent, such as mosquito vectors of malaria or dengue fever. Examples of such measures abound. Immunization of children prevents diseases such as tetanus, pertussis, and diphtheria. Chlorination of drinking water prevents transmission of waterborne gastroenteric diseases. Wearing seat belts in motor vehicles prevents much serious injury and death in road crashes. Reducing the availability of firearms reduces injury and death from intentional, accidental, or random violence.
Primary prevention also includes activities within the health system that can lead to better health. This may mean, for example, setting standards and ensuring that doctors not only are informed of appropriate immunization practices and modern prenatal care, but also are aware of their role in preventing cerebrovascular, coronary, and other diseases like cancer of the lung. In this role, the health-care provider serves as a teacher and guide, as well as a diagnostician and therapist. Like health promotion, primary prevention does not depend on doctors alone: both work to raise individual consciousness of self-care, mainly by raising awareness and information levels, empowering the individual and the community to improve self-care, to reduce risk factors, and to live healthier lifestyles.



Secondary Prevention
Secondary prevention is the early diagnosis and management to prevent complications from a disease. Public health interventions to prevent spread of disease include the identification of sources of the disease and the implementation of steps to stop it, as shown in Snow’s closure of the Broad Street pump. Secondary prevention includes steps to isolate cases and treat or immunize contacts so as to prevent further cases of meningitis or measles in outbreaks. Needle exchange programs or distribution of condoms in schools or colleges help to prevent the spread of STDs and AIDS.
All health care providers have a role in secondary prevention, for example, in preventing strokes by early and adequate care of hypertension. The child who has an untreated streptococcal infection of the throat may develop complications which are serious and potentially life-threatening, including rheumatic fever, rheumatic valvular heart disease, and glomerulonephritis. When a patient is found to have elevated blood pressure, this can be managed by weight loss, physical fitness, smoking cessation, and the taking of medication, which together lower the risk of stroke. In the case of injury, competent emergency care, safe transportation, and good trauma care may reduce the chance of death and/or permanent handicap. Screening and high quality care in the community prevents complications of diabetes, including heart, kidney, eye, and peripheral vascular disease; they can also prevent hospitalizations, amputations, and strokes, thus lengthening and improving the quality of life. Health care systems need to be actively engaged in secondary prevention, not only as individual doctor’s services, but also as organized systems of care.


Tertiary Prevention
Tertiary prevention involves activities directed at the host but also at the environment in order to promote rehabilitation, restoration, and maintenance of maximum function after the disease and its complications have stabilized. The person who has undergone a cerebrovascular accident or trauma will come to a stage where active rehabilitation can help to restore lost functions and prevent recurrence or further complications.
Treatment for a myocardial infarction or a fractured hip now includes early rehabilitation in order to promote maximum recovery and restoration of function. Providing a wheelchair, special toilet facilities, doors, ramps, and transportation services for paraplegics are often the most vital factors in rehabilitation. Public health agencies work with groups in the community with interest in promoting help for specific categories of disease or disability, to reduce discrimination, to eliminate physical or social barriers, to promote community awareness, and to finance special equipment or other needs of this group. Close follow-up and management of chronic disease, physical and mental, requires home care and assuring an appropriate medical regimen including drugs, diet, exercise, and support services. The follow-up of chronically ill persons to supervise the taking of medications, to monitor changes, and to support them in maximizing their independent capacity in activities of daily living are essential elements of the New Public Health.