what does "natural course of disease" mean

The natural history of disease is the course a disease takes in individual people from its pathological onset ("inception") until its resolution (either through complete recovery or eventual death). The inception of a disease is not a firmly defined concept. The natural history of a disease is sometimes said to start at the moment of exposure to causal agents.

Full Answer

What is natural history of a disease?

Natural history of disease refers to the progression of a disease process in an individual over time, in the absence of treatment. For example, untreated infection with HIV causes a spectrum of clinical problems beginning at the time of seroconversion (primary HIV) and terminating with AIDS and usually death.

What does it mean when a death is ‘natural’?

Here is a look inside the process doctors go through to determine whether a death was “natural,” and what exactly that means (or doesn’t). What are ‘natural causes’? It might not seem to mean much at all. But when a death certificate says a person’s death was “natural,” it is really ruling out the involvement of external causes.

What is an example of a natural cause of death?

For example, on a death certificate where the manner of death is listed as natural, the immediate cause of death could be a tear in the heart wall that happened minutes before death, and the underlying causes could be a heart attack or heart disease that took place in the days, months and years before death. How common is ‘natural’ death?

What is the range of the disease process?

In others, the disease process may result in illness that ranges from mild to severe or fatal. This range is called the spectrum of disease. Ultimately, the disease process ends either in recovery, disability or death. For an infectious agent, infectivity refers to the proportion of exposed persons who become infected.

What does the term natural history of disease mean?

Natural history of disease refers to the progression of a disease process in an individual over time, in the absence of treatment. For example, untreated infection with HIV causes a spectrum of clinical problems beginning at the time of seroconversion (primary HIV) and terminating with AIDS and usually death.

What are the four stages of natural history of disease?

Events that occur in the natural history of a communicable disease are grouped into four stages: exposure, infection, infectious disease, and outcome (see Figure 1.6).

What is the nature of a disease?

Diseases are abnormal conditions that have a specific set of signs and symptoms. Diseases can have an external cause, such as an infection, or an internal cause, such as autoimmune diseases.

What Is A Natural History of Disease Study?

A natural history study collects information about the natural history of a disease in the absence of an intervention, from the disease's onset until either its resolution or the individual's death.

Why do you need to know the natural history of disease?

Understanding the natural history of a disease is an important prerequisite for designing studies that assess the impact of interventions, both chemotherapeutic and environmental, on the initiation and expression of the condition.

Are diseases natural?

If we know something is a disease prior to any empirical discovery about its nature, then disease is not a natural kind.

What are the 4 types of diseases?

There are four main types of disease: infectious diseases, deficiency diseases, hereditary diseases (including both genetic diseases and non-genetic hereditary diseases), and physiological diseases.

How many diseases are there in the world 2021?

The focus is really on rare diseases, but a credible case can be made that there are at least 10,000 diseases in the world, though there is likely more.

How is disease caused?

Infectious diseases commonly spread through the direct transfer of bacteria, viruses or other germs from one person to another. This can happen when an individual with the bacterium or virus touches, kisses, or coughs or sneezes on someone who isn't infected.

What are the 5 stages of disease?

The five periods of disease (sometimes referred to as stages or phases) include the incubation, prodromal, illness, decline, and convalescence periods (Figure 2). The incubation period occurs in an acute disease after the initial entry of the pathogen into the host (patient).

What is an incubation period of a disease?

The incubation period is the time from exposure to the causative agent until the first symptoms develop and is characteristic for each disease agent.

What are the 4 stages of pathogenesis?

Stages of Pathogenesis. To cause disease, a pathogen must successfully achieve four steps or stages of pathogenesis: exposure (contact), adhesion (colonization), invasion, and infection.

What are the 4 stages of communicable illness?

The natural history of an untreated communicable disease has four stages: stage of exposure, stage of infection, stage of infectious disease, and stage of outcome.

What are the stages of a disease?

The five periods of disease (sometimes referred to as stages or phases) include the incubation, prodromal, illness, decline, and convalescence periods (Figure 2). The incubation period occurs in an acute disease after the initial entry of the pathogen into the host (patient).

What is the first stage of an infectious disease?

1. Incubation. The incubation stage includes the time from exposure to an infectious agent until the onset of symptoms. Viral or bacterial particles replicate during the incubation stage.

Health Psychology

As with the age of onset and course of disease, information about symptoms, prognosis, and treatments also differ depending upon the specific condition. Many genetic disorders are associated with varying degrees of mental retardation, although some are associated with normal levels of intelligence.

Behavioral Medicine

Claus Vögele, in International Encyclopedia of the Social & Behavioral Sciences (Second Edition), 2015

Defense Mechanisms

DMs appear to be not merely correlates of the disease but may also play a role in regard to the course of disease and prognosis. Thus, in female migraine patients self-aggrandizement was related to headache frequency and reduced temporal blood flow (Passchier et al., 1988 ).

Multiple Sclerosis

An important feature of multiple sclerosis is the marked variability in neurologic symptoms and clinical course. Four different types of disease course have been described. Most patients present with relapsing–remitting disease. An individual develops neurologic symptoms and signs over hours to days and typically recovers in 6–8 weeks.

Health Psychology

Clearly, psychology and psychologists are key players in the theater of life with arthritis. The chronic, painful, disabling nature of the condition combined with an unpredictable disease course of exacerbations and remissions, necessitates a continuous process of adaptation.

Respiratory Disorders: Psychosocial Aspects

Andreas von Leupoldt, in International Encyclopedia of the Social & Behavioral Sciences (Second Edition), 2015

Prion Diseases

A new variant of CJD was described in 10 patients in the United Kingdom in 1996. These patients had a mean age of 29 years and presented with psychiatric disturbances, whereas signs more typical of CJD developed later in the course of disease.

What is natural history?

Natural history of disease refers to the progression of a disease process in an individual over time, in the absence of treatment. For example, untreated infection with HIV causes a spectrum of clinical problems beginning at the time of seroconversion ...

What is a person who is infectious but has subclinical disease called?

Such persons who are infectious but have subclinical disease are called carriers. Frequently, carriers are persons with incubating disease or inapparent infection. Persons with measles, hepatitis A, and several other diseases become infectious a few days before the onset of symptoms.

What is the stage of subclinical disease?

This stage of subclinical disease, extending from the time of exposure to onset of disease symptoms, is usually called the incubation period for infectious diseases, and the latency period for chronic diseases.

What is the difference between pathogenicity and infectivity?

For an infectious agent, infectivity refers to the proportion of exposed persons who become infected. Pathogenicity refers to the proportion of infected individuals who develop clinically apparent disease.

What is the definition of virulence?

Virulence refers to the proportion of clinically apparent cases that are severe or fatal. Because the spectrum of disease can include asymptomatic and mild cases, the cases of illness diagnosed by clinicians in the community often represent only the tip of the iceberg.

Can a disease process end in death?

This range is called the spectrum of disease. Ultimately, the disease process ends either in recovery, disability or death.

Can an undiagnosed person transmit a disease to others?

Unfortunately, persons with inapparent or undiagnosed infections may nonetheless be able to transmit infection to others. Such persons who are infectious but have subclinical disease are called carriers.