Some important definitions: Health:it is a physical, mental and social well-being wait state, and not only the absence of disease or illness. Disease:it is the last stage of a process that has been developed with time and means a break of the own system of natural defense.
Natural history of the Disease It is the natural evolution of any pathological process, from its beginning to its resolution, without any help of the man.
Natural history of the Disease Pre-Pathogenic period:it corresponds to the time in which the people are healthy, that is to say, are in balance with it’s atmosphere. Pathogenic period:it corresponds at the beginning of the disease, even before the symptoms appear.
Pre-Pathogenic period In this period the three elements in a disease interacts, that is formed by: Host Environment Agent
Pre-Pathogenic period Host Human, organ or tissue Environment Home, school, communityor world, Agent Physical: temperature, water, air, etc. Chemistry: chemical substances and/or poison Biological: Virus, Bacteria, fungi, parasite
Pre-Pathogenic So that one appears the disease is necessary that all the components of the elements are present. Lacks of one them can not give the interaction and disease doesn’t appear. When the three elements of the triad enter in balance, the pathological process begins in the guest.
Pathogenic Sub-clinic Stage or Incubation period Clinic Horizon Clinic Stage
Pathogenic Signs and Unspecific Symptoms: Fiber, general discomfort. Specific Symptoms : The manifestations of each pathology. Chronic:The pathology appears with signs and chronic symptoms.
Pathogenic Complications: Other affections in the organism become jumbled. Sequel: The people present/display some type of disability or permanent alteration. Death: Final stage of the disease.
Natural history of the disease PREPATOGENIC PERIOD The individual is healthy. There is balance between the Agent, the Guest and his environment PATOGENIC PERIOD The individual is ill. Imbalance between the Agent, the Guest and his environment exists CLINIC STAGE Clinical Horizon Defensive mechanisms. Immune response of the Guest. Specific unspecific and specific Mechanisms of the pathogenic agent local or systemic SUB-CLINIC STAGE Entrancedoor: Period of Incubation (period of latency, adaptation, reproduction, local expansion, histopathologic changes and/or systemic dissemination)
Pathogenic Period In anyone of these consecutive stages, before the death, the disease can be aborted, that is to say, to return to the Pre-Pathogenic Period.
Primaryprevention Secondary prevention Tertiary prevention REHABILITACION DIAGNOSTIC & TRATMENT PROMOTION OF THE HEALTH SPECIFIC PROTECTION LIMITATION OF THE DISSABILITY PATOGENESIS PRE-PATOGENESIS Leavell HR y Clark F: Preventive medicine forthe doctor in hiscommunity. 1965. Levels of Levell & Clark
Natural history of the Disease and Levels of Medical Prevention