Host :

• A person/ living animal that affords lodgment to agents of diseases under natural conditions.

Demographic characteristics: age, sex

ethnicity, etc.

Biologicalcharacteristics: Genetic,

Biochemical levels of blood,Physiological functions: BP,

etc.

Lifestyle characteristics:

personality traits,living habits

Environment :

• All (living or non-living) that is external to the individual human host in which he is in constant interaction

Physical:Air, water, soil, housing,

Climate, etc.

Biological:Insects, rodents, animals, plants,

other human beings

Psychosocial:Cultural values, habits,

beliefs, attitudes, moral, social interaction,

etc.

Risk factors:

• An attribute or exposure that is significantly associated with the development of the disease

• Ex. Ht. Disease: Smoking, high BP, elevated serum cholesterol, diabetes, obesity, lack of exercise

Risk factors:

• 1) Additive or synergestic (multiplicative)• - smoking and aniline in the production of bladder

cancer : additive• -smoking and high BP in heart disease: synergistic• 2) May be:• a) Contributory – lack of physical exercise in

heart disease OR• b) Predictive (in statistical sense) – illiteracy in

perinatal mortality

Risk factors:

• 3) May be:• a) Modifiable – smoking, BP,obesity, physical fitness

OR• b) Non-modifiable – age, sex, family history, genetic

factors • 4) May be: • a) Individual – age, sex, smoking OR• b) Community – air pollution, water pollution, lack of

basic sanitation, etc.

Spectrum of disease

- Subclinical infection (inapparent)-Unrecognized sickness- Mild-Moderate- Severe- Death

Disease

-Graphic representations of variations in the manifestations of diseases-Spectrum of disease is best seen in diseases such as syphilis, leprosy

Iceberg of diseases ( Iceberg phenomenon)

Iceberg of diseases ( Iceberg phenomenon)

• 1) Disease in a community may be compared to an iceberg

• 2) Floating tip of iceberg- what the physician sees• - clinical cases with illness• 3) Submerged portion represents the hidden mass

of diseases – latent, inapparent, presymptomatic, undiagnosed, indignant

Iceberg of diseases ( Iceberg phenomenon)

• 4) Varies from disease to disease ; submerged portion greatest in non-communicable diseases – HPT, DM

• 5) Submerged portion – constitutes reservoir of infection

• 6) Major challenge is to detect the undiagnosed portion

Determinants Of Health

Dr. Adinegara Bin Lutfi Abas

Health- absence of disease

Disease-impairment of

human body affecting

vitalfunctions

Determinants Of Health :

Heredity

Environment Lifestyle

Socio-economicconditions

Health and family welfare services

Heredity

• The genetic transmission of characteristics from parent to offspring

• The physical and mental traits of human being are determined by genes from conception

• Diseases of genetic origin:• - chromosomal anomalies, errors of

metabolism, mental retardation, etc.

Health from genetic stand-point

• “State of individual based upon absence of defects of genes and absence of any abnormality in respect to total amount of chromosome in karyotype.”

Environment

• All that is external to the individual human host.

Environment

Physical Biological Psychosocial

1. Housing2. Water supply3. Waste treatment4. Workplace conditions - lighting - ventilation - humidity

1. Domestic / wild animals2. Vectors in propagation of diseases - mosquitoes, flies, rodents3. Bacteria/ virus/ protozoa/ etc.

Stress - workload - relationship with peers, family

Lifestyle

• “The way people live”• Composed of cultural and behavioural patterns

and personal habits (eg. Smoking, alcoholism)• Lifestyle diseases – coronary heart disease,

obesity, drug addiction, etc.• However, take note of positive lifestyle factors: • - exercise, adequate nutrition, etc.

• The Healthy Lifestyle Campaign of the Ministry of Health was launched in 1991. 

• Cardiovascular Diseases (1991)

• AIDS (1992)

• Food Hygiene (1993)

• Promotion of Environmental Health (2002).

Socio-economic conditions

• 1) Economic status

• 2) Education

• 3) Occupation

• 4) Other factors- political system

1) Economic status

• Per capita GNP most widely accepted measure of economic performance

• Determines purchasing power, standard of living, quality of life, family size, pattern of disease and deviant behaviour

• Strong correlation between GNP and life expectancy

• Affluence associated with obesity, CHD, diabetes

• 2) Education-• Illiteracy coincides with poverty, malnutrition, ill-

health, high infant and child mortality rates• 3) Occupation – • The unemployed shows a higher incidence of ill-

health and death• 4) Political system-• Percentage of GNP spent on health (WHO

recommends a minimum of 5%)

Health and family welfare services

• Purpose is to increase health status of population

• Include

• - immunization of children

• - provision of safe water supply

• - care of antenatal mothers and children

• - food quality control

An effective health service:

• 1) Must reach the social periphery

• 2) Equitably distributed

• 3) Accessible at a cost the country and the community can afford

• However there is NO correlation between medical density and life expectancy