The field of medicine has a vast history that has enabled it to grow to what we see in the modern day. There exist various theories that define health and explain the causes of diseases. These theories have contributed to the success and application of modern day medicine. In the past three significant theories have been proposed regarding the causes of diseases. These theories are the humoral theory, the germ theory and the anatomical concept of disease. This paper seeks to discuss these theories in brief.
The humoral theory
This theory has its origin from Hippocratic medicine probably between 430 and 330 BC. Humoral is a derivative from the word humor, which means a fluid. In this times it was believed that the human body had four properties or humors which are black bile (also known as melancholy), yellow bile, blood and phlegm (Herbst, 2008, pg. 7). The humoral theory further states that there will be an imbalance if one of the four humors is affected. This would result into physical symptoms. Health was define as the proper humoral balance, an imbalance of the humors resulted in disease (Lloyd, 1978, pg. 262). Physicians associated each humor with a season of the year e.g., physicians diagnosed a cold caught in winter because of an imbalance in phlegm. Perceived humoral imbalance determined the choice of drugs administered after thorough analysis by the physician.
The germ theory
This theory states that many diseases are caused by the presence and action of specific micro organisms (Alcamo,1996, pg. 7). This theory did not get direct approval when it was first proposed but over the years, it has been applied in medical microbiology. Joseph lister, Louis Pasteur and Robert Koch argued for the acceptance of the germ theory in the 19th century. Anton van leeweuwenhoek and john snow had previously contributed to the formation of the germ theory through the discovery of microorganisms.
Anatomy concept of disease
During the 19th century, Giovanni Baptista Morgagni proposed the concept in which he used pathology and human anatomy to find out the causes of diseases. This study bridged a huge gap between patient symptoms and pathology making a connection between symptoms on the outside and diseases in the inside. Morgagni argued that disease could be traced to a particular pathology or disturbance in individual organs (Reiser, 1978, pg. 17). Morgagni laid the foundation of pathological anatomy by comparing clinical findings to post moterm findings. The anatomy concept of disease explains that disease often affects anatomy and a change in anatomy can cause a disease. Methods of seeing into the body have become the mainstay in the diagnosis of the disease. Advance in technology has enabled doctors to see into the body and observe internal structures without surgery e.g. the use of x-rays (Beers, 2006).
Differences between each theory
The humoral theory proposes that the occurrence of a disease is due to change in the environment. Each humor was associated with one of the four seasons, and each had unique characteristic qualities such as hotness, coldness, dryness and wetness. Physicians did not carry out physical examinations of the patient but relied on the symptoms and inspection of the body fluids such as blood and urine. This theory encouraged application of preventive medicine and hygiene during this specific period when focus on hygiene standards was a constant growing concern.
The germ theory states that specific microorganisms cause most diseases. This theory revolutionized the practice of medicine and the understanding of disease. The germ theory does not consider environmental influences such as climate important in understanding diseases. This theory does not relate the anatomy of the human body to diseases. This theory led to application of hygienic practices in order to prevent infections.
The anatomy concept of disease proposes that there is a relationship between disease and the body organs. This theory stipulates that diseases affect organs and there is need to understand the anatomy and functioning of these organs. An alteration in the functioning of the organ will lead to disease development when the prevailing factors encourage its development.
Historical significance of each theory
The humoral theory was an advance towards modern view of human health as opposed to the previous view that diseases had religious origin. It also encouraged the application of public health principles and preventive medicine. The germ theory was central in preventing disease outbreaks. It also led to the creation of vaccines against some diseases such as cholera and rabies. The knowledge that vaccines caused diseases led to the use of antiseptic techniques during treatment and surgery. Anatomy concept of disease encouraged the use of surgery and the study of human organs in order to relate disease to the specific organs.
The application of these three theories in the past has led to significant development in the field of medicine. It is important to understand the roots of modern day medicine because only then can we appreciate the efforts of previous generations. This is an attribute of recent developments in the medical field have been ongoing constant evolution resulting in better service provision. This will also encourage the current generation of scientist and physicians to seek better methods of treatment. Evaluation of our past will enable us rectify our previous mistakes and contribute to the future significantly.