Upon further discussion from my recent article on culture-bound disorders, I feel it’s useful to post an in-depth semantic insight on the distinction social scientists make between “disease” and “illness”.
Disease can lead to illness. Equally, illness can lead to disease. In other words, a physiological thing can lead to a psychosocial thing and a psychosocial thing can lead to a physiological thing. Sometimes there is disease without illness, illness without disease, but usually it’s the concurrence of disease and illness. The important difference is that disease is objectifiable and illness is a subjective experience.
Disease is a physical reality defined by a pathophysiological condition in a person; that is, an agent (pathogen) physically, and hence biologically, manifests in a somatic (bodily) way. The important distinction for disease is as an agent that is debilitating or deteriorative in some way or that is notably different than a normal healthy state. Disease states can include injury, infections, nutritional deficit or surfeit, genetic disease, chronic disease, and behavioral disorders. The main theme in these being an impairment of regular functions of the body. An American example can be over-eating and obesity. This dysfunction, based on subsistence behavior and surfeit, can certainly be a disease state at certain levels. It can cause various problems with the heart, ease of passage of blood through arteries, and psychological affect with respect to self-image and physical abilities. Interestingly, this disease condition is not usually interpreted in terms of illness. It has become accepted by society and the symptoms are not always salient. In reality, it is an illness as well, as there are psychological and social detriments that accompany the disease-like conditions.
Illness is viewed as a human mental state. It is a state of mind based on the knowledge or belief of a disease within one’s body. The perceived dysfunction from a lack of health, as well as cultural and social factors, define an illness experience. Illness can be thought of as the subjective experience that a person has in response to suffering from the effects of a disease agent. It is a state of acknowledgment of unhealth and usually leads to behavior that intends to alleviate or cure the symptoms. Illness is created when a disease is made into an actuality. This can be done through the interpretation of a physician or healer or through any other realization process. Once a person believes they have a disease they become ill. Culture defines the subjective qualities of one’s illness. It determines how an individual expresses their suffering and the ideologies tied to their experience. This is closely related to sickness, which is a social role, and how disease or illness can manifest socially via others’ and the self’s perception of their place in society due to their health. The key point is illness is a personal manifestation of a symptom or symptoms. This can be exemplified in any case that someone is debilitated or disabled due to a disease. Their psychological state may contain fear, sorrow, frustration, as well as hope and anticipation. The ill person is noticeably different in personality and is likely distracted, with their attention focused on the state of their bodily condition. In terms of how this relates in modern biomedicine, illness is separate from disease, say by a physician, in that disease is the reduction or ignorance of a person’s idiosyncratic and culturally defined perception (i.e. their illness) to a single, physical cause.
To elucidate and wrap it up, we can say disease and illness are interrelated, whether they coexist or not. When disease is realized or imagined by the afflicted, a malady is formed in the mentality of the individual. This brings the impairment of the body from a strictly somatic realm into one emphasizing emotion, mood, and perspective. Studying illness properly can be a profound insight into how disease of the body can vary in its psychological impact based on an individual’s worldview and beliefs – as determined by their sociocultural environment.
Hope that clears up the difference between disease and illness. Let me know if it’s not clear how sickness fits in best as a social role rather than a physical or experiential state.