Concepts of control & modes of intervention

CONCEPTS OF CONTROL

Disease control

The term “disease control” describes (ongoing) operations aimed at reducing:

I. The incidence of disease.

II. The duration of disease, and consequently the risk of transmission.

III. The effects of infection, including both the physical and psychosocial complications; and

IV. The financial burden to the community.

DISEASE ELIMINATION:

♣ “Regional elimination”

♣ Describes interruption of transmission of disease.

Ex: elimination of measles, polio.

DISEASE ERADICATION

Eradication literally means to “tear out by roots”.

It implies termination of all transmission of infection by extermination of the infectious agent.

As the name implies, eradication is an absolute process, and not a relative goal.

♣ The word eradication is reserved to cessation of infection and disease.

♣ Smallpox, Polio, measles

♣ Disappointment in the eradication programmes mounted against malaria, yaws, plague, kala-azar and yellow fever.

MONITORING AND SURVEILLANCE:I) Monitoring:

“The performance and analysis of routine measurements aimed at detecting change in the environment or health status of population". example-air pollution

“The continuous oversight of activities to ensure that they are proceeding according to plan.

II SURVEILLANCE: “The continuous scrutiny of the factors that determine

the occurrence and distribution of disease and other

conditions of Ill-health”

a. To provide information about new and changing trends in the health status of a population, e.g., morbidity, mortality, nutritional status or other indicators and environmental hazards, health practices and other factors that may affect health.

b) To provide feed-back which may be expected to modify the policy and the system itself and lead to redefinition of objectives, and

c) Provide timely warning of public health disasters so that interventions can be mobilized.

Sentinel surveillance:

A method for identifying the missing cases and thereby supplementing the notified cases is required.

Reporting biases are minimized and feed-back of information to the providers is simplified.

Evaluation of control

Evaluation is the process by which results are compared with the intended objectives, or more simply the assessment of how well a programme is performing.

Modes of intervention

“Intervention” can be defined as any attempt to intervene or interrupt the usual sequence in the development of disease in man.

1. Health promotion

2. Specific protection

3. Early diagnosis and treatment

4. Disability limitation

5. Rehabilitation

1. Health promotion:

Health promotion is “the process of enabling people to increase control over, and to improve health.”

i health education

ii environmental modifications

iii nutritional interventions

iv lifestyle and behavioral changes

(i) Health education:“the extension to all people of the benefits of

medical, psychological and related knowledge is essential to the fullest attainment of health.

( i i ) Environmental modifications:♦ Safe water.

♦ Sanitary latrines.

♦ Improvement of housing.

( i i i ) Nutrit ional interventions:

( iv) Lifestyle and behavioral changes:

2. Specif ic protection:The following are some of the currently available interventions aimed at specific protection.

♦ immunization

♦ use of specific nutrients

♦ chemoprophylaxis

♦ protection against occupational hazards

♦ protection against accidents

♦ Protection from carcinogens

♦ of allergens

♦ the control of specific hazards in the general

environment

Health Protection:Health protection is defined as "The provision of conditions or normal mental and physical functioning of the human being individually and in the group. It includes the promotion of health, the prevention of sickness and curative and restorative medicine in all its aspects.

Early diagnosis and treatment: “The detection of disturbances of Homoeostatic and compensatory mechanism while biochemical, morphological, and functional changes are still reversible”

not economic but reduces high morbidity and mortality

Mass Treatment:The rationale for a mass treatment programme is the

existence of at least 4-5 cases of latent infection for each clinical case of active disease in the community.

4. Disability limitation:When a patient reports late in the pathogenesis phase, the mode of intervention is disability limitation.

The objective of this intervention is to prevent or halt the transition of the disease process from impairment to handicap.

Concept of disability:

Disease Impairment Disability handicap

(i) Impairment:“any loss or abnormality of psychological, physiological or anatomical structure or function.

(ii) Disability:This inability to carry out certain activities is termed

“disability”

“any restriction or lack if ability to perform an activity in the manner or within the range considered normal for a human being”.

(iii) Handicap:“a disadvantage for given individual, resulting from an impairment or a disability, that limits or prevents the fulfillment of a role that is normal (depending on age, sex, and social and cultural factors) for that individual”.

Accident ………… Disease (or disorder)Loss of foot……… Impairment (extrinsic or

intrinsic)Cannot walk……… Disability (objectified)Unemployed ……… Handicap (socialized)

Disability prevention:(a) Reducing the occurrence if impairment, viz. immunization against polio (primary prevention);

(b) Disability limitation by appropriate treatment (secondary prevention);

(c) Preventing the transition of disability into handicap (tertiary prevention)

5. Rehabil itation:“The combined and coordinated use of medical, social, educational and vocational measures for training and retraining the individual to the highest possible level of functional ability.

a) Medical rehabilitation – restoration of function

b) Vocational rehabilitation – restoration of the capacity to earn a livelihood.

c) Social rehabilitation – restoration of family and social relationships

d) Psychological rehabilitation – restoration of personal dignity and confidence.