Natural Disease History & Epidemiological Research

• Natural disease history is a description of the development of a disease in an individual that occurs naturally
• Also is the process of disease development without deliberate human intervention.

Epidemiological Research Framework

• Epidemiological research is divided into 3 main areas
• Etiological Research
• Prognostic Research
• Intervention Research
• This division is based on the stages of disease development and preventive measures.

Epidemiological Research Types

• Etiological Research identifies disease causes, interrelationships, and impact magnitude.
• Prognostic Research studies risk factors and predicts disease outcomes.
• Intervention Research evaluates intervention efficacy/effectiveness, including primary, secondary, and tertiary prevention. Bhisma (2003)

Benefits of Researching Natural Disease History

• Diagnostics can use incubation periods to guide disease identification
• Knowing biological properties of pathogenic germs helps disease prevention
• Treatment uses information for initial therapy because knowing the course of a disease is key for early interventions
• Prevention targets identified pathogens and disease progression chains to find crucial intervention points

Stages of Natural Disease History

• The image shows the RIWAYAT PERJALANAN PENYAKIT PADA MANUSIA

Pre-Pathogenesis Stage

• The host is healthy and normal
• There is interaction between the host and agent, but the agent is still outside the host
• When host, agent, and environment interactions change, the host becomes more susceptible or the agent more virulent and penetrates the host (entering pathogenesis)

Pathogenesis Stage

• This occurs when there is an imbalance of the epidemiological triad
• The stage has 3 sub-stages:
• Incubation: Agent enters host until symptoms appear
• Early Disease: Initial symptoms start mildly
• Advanced Disease: The disease has progressed, causing pathologies and symptoms

Post-Pathogenesis Stage

• Represents the end of the disease course
• It can take these forms:
• Complete Recovery: The agent is gone, and the host fully recovers
• Recovery with Disability: The agent is gone, but the host isn't fully recovered (there is residual damage/disability)
• Carrier: The agent persists, the host recovers, but some potential for agent-related issues remains
• Chronic: The disease appears halted because there is no change to the disease, but the host remains ill
• Death: The disease progression stops because the host dies before recovering

Epidemiological Prevention Levels

• Primordial Prevention prevents the emergence of social, economic, and cultural lifestyles that increase disease risk.
• Primary Prevention reduces the incidence of a disease.
• Secondary Prevention reduces the severity and complications of a disease.
• Tertiary Prevention reduces the number and impact of complications.

HIV/AIDS Case Study

• HIV/AIDS follows a path of natural disease
• The virus needs 5-10 years or more to reach the AIDS phase.
• Stages of HIV/AIDS:
• Initial Stage (Window Period)
• Second stage (HIV Asymptomatic/Latent Period)
• Third Stage (with Disease Symptoms)
• AIDS

Conclusion

• The natural history of a disease illustrates its progression without medical intervention, spanning pre-pathogenesis to outcomes like recovery, disability, or death. Epidemiological research is key for understanding etiology/risk factors/intervention effectiveness. Disease prevention includes primordial, primary, secondary, and tertiary levels. Comprehending a disease's natural path & using stage-specific prevention boosts disease management, lessens illness/death, & betters public health overall..