What is Health?

Health is an essential factor for all human beings. For all humans, health is a critical factor. An individual's ability to meet life's challenges and retain his or her capacity for optimal functioning is reflected in his or her condition of health. This needs the physical, mental, and biological parts of one's constitution to maintain a degree of functioning that has a favorable influence and support for one another.

What is Public health?

"Public health" has been defined as the science and art of preventing disease, extending life, and increasing quality of life via coordinated efforts and informed decisions made by society, organizations, communities, and individuals. The examination of a population's health determinants and the threats it faces is the foundation of public health. The public can range in size from a few individuals to a village or a whole city. A pandemic might spread over numerous continents. The concept of health takes into account physical, psychological, and social well-being. The overall goal of public health is to promote the health of whole populations. These populations can range in size from a single neighborhood to an entire country or area of the globe. Public health saves you money, improves the health of children and adults in a community. Public health promotes good health to all.

What is Epidemiology?

Epidemiology is a medical science branch, and epidemiology is the fundamental science of preventive and social medicine. Epidemiology is derived from the word epidemic, "Epi", which means among, "demos," which means people, and "logos," which means study. Epidemiology is a method for determining the causes of disease and health outcomes in communities. The patient in epidemiology is the community, and individuals are evaluated as a whole. Epidemiology is the scientific, systematic, and data-driven study of the distribution of health-related states and events in specific populations, including frequency, pattern, and determinants such as causes and risk factors. It's also the application of this research to the management of health issues. The current interest of medical science in epidemiology has given rise to newer off-shoots such as infectious disease epidemiology, chronic disease epidemiology, cancer epidemiology, and malaria epidemiology, etc.

Aims of Epidemiology

According to the International Epidemiological Association (IEA), epidemiology having their major goals, are:

  • To disseminate the magnitude and distribution of health and disease problems in the human population.
  • Identifying disease pathogen risk factors
  • To provide data necessary for the planning, implementation, and evaluation of disease prevention and control programs, as well as disease treatment among the population.

Uses of Epidemiology

Studying the historical rise and fall of disease in the population, studying the disease profile and time trends in the human population, and identifying the emerging health problems in the current trends are three uses of epidemiology. After this process of epidemiologist diagnosis, the community generally refers to the identification of the health problems of a community in terms of mortality and morbidity rates and ratios. Then after finding the health problems, we have to do planning and evaluation. Following this, an epidemiologist assesses the risk variables for the individual. It's a crucial task for an epidemiologist. Then determine the disease's syndrome, and last, complete the disease's natural history. Finally, look into the disease's causes and risk factors.

Role of Epidemiologist

Epidemiologists investigate disease epidemics, including the origins, locations, and effects on diverse communities, intending to use this information to help avoid future outbreaks. Epidemiologists assist in informing the public about ways of maintaining and improving public health. Epidemiologists have many roles and responsibilities. They have helped to reduce the burden of disease and improve public health.

Epidemiological triad

The epidemiological triad is one of the most used models for showing disease causation. Infectious diseases, non-infectious diseases, and accidents or injuries are all investigated using the triad. The agent, environment, and host are all part of the epidemiological triangle. The microorganism that causes the disease in question is referred to as the agent. Bacteria, viruses, fungi, and parasites are all examples of agents. The agent infects the host, which is the disease-infected organism. A host does not have to become ill in order to act as a carrier for an agent; hosts can act as carriers for an agent even if they do not exhibit any outward symptoms of the disease. Outdoor factors can affect the epidemiological outbreaks that are called the environment.

Epidemiology of Cancer

Cancer epidemiology is a subfield of epidemiology that studies the factors that influence cancer to deduce possible trends and causes. The study of cancer epidemiology uses an epidemiological method to find the causes and risk factors of cancer and develop improved treatments. Epidemiologists are still looking for cancer-causing variables such as cigarette use, obesity, and ultra-violet radiation as well as cancer-preventive ones such as physical activity and a healthy diet. This study adds to the body of knowledge that may be used to inform public health recommendations and legislation. By defining the spread of cancer and finding risk factors for cancer, epidemiology plays a critical role in cancer prevention and control. Descriptive, ecologic, cross-sectional, and analytic cohort, case-control, and intervention studies are examples of epidemiologic study designs. In India, the most prevalent cancers are breast cancer, cervical cancer, and oral cancer.

The diagrammatic representation of Epidemiology of cancer is shown in the figure.
CC0 1.0 | Image Credits: https://commons.wikimedia.org | Mikael häggström

Context and Applications

This topic is significant for professional exams such as undergraduate and postgraduate courses, especially for;

Bachelor of Science in Epidemiology and Public Health.

Masters of Science in Epidemiology and Public Health.

Masters of Science in Public Health.

Practice Problems

Epidemiologists are interested in learning more about ______.

  1. The frequency and geographic distribution of disease
  2. The cause of disease and how to prevent the disease
  3. Causual relationship between disease
  4. All of the bove.

Answer: Option 4 is correct.

Explanation: Epidemiology is a branch of medicine that studies how, where, and why diseases originate, as well as how to prevent them from spreading.

Question 2: The interest of epidemiologist is to learn about_____________.

  1. The causes of disease and how to cure the disease
  2. The casual relationship between disease
  3. To study the geographic and frequency of the disease
  4. All of the above

Answer: Option 4 is correct.

Explanation: Epidemiology is a branch of medicine concerned with understanding how, where, and why diseases arise, as well as how to effectively prevent their spread.

Question 3: Malaria caused by __________.

  1. Mosquitoes
  2. Plasmodium
  3. Tick
  4. Blood cells

Answer: Option 2 is correct.

Explanation: Plasmodium causes malaria. They are transmitted from host to host unintentionally via blood-sucking mosquitoes.

Question 4: The mode of transmission of an infectious pathogen from the environment to a susceptible host is referred to as_____.

  1. Carrier
  2. Reservoir
  3. Transmission
  4. Host

Answer: Option 2 is correct.

Explanation: The habitat in which an infectious agent generally lives, matures, and multiplies is known as the reservoir. Humans, animals, and the environment all have reservoirs. The reservoir might be the source of an agent's transmission to a host or it could not.

Question 5: An infectious disease that spreads rapidly and may possibly reach the entire world is called as____________.

  1. Pandemic
  2. Hyperendemic
  3. Epidemic
  4. None of the above

Answer: Option 1 is correct. 

Explanation: A pandemic is an endemic disease spread over the country or continents. 

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