Major Non-Communicable and Genetic Diseases
In the previous chapter, we studied communicable diseases, which are caused by pathogens and can spread from one person to another. However, a massive portion of global and national health challenges comes from diseases that are not infectious. These are classified as Non-Communicable Diseases (NCDs) and Genetic Diseases.
What are Non-Communicable Diseases (NCDs)?
Non-communicable diseases are chronic health conditions that last for a long period and generally progress slowly. The defining characteristic of an NCD is that it cannot be transmitted from an infected person to a healthy person. You cannot “catch” an NCD by being near someone who has it.
Instead of pathogens, NCDs are caused by a complex combination of four main factors:
- Physiological factors: Changes within the body, such as high blood pressure or high blood sugar.
- Behavioural factors: Unhealthy lifestyle choices, such as poor diet, lack of physical exercise, tobacco use, and alcohol consumption.
- Environmental factors: Exposure to air pollution, harmful chemicals, or radiation.
- Genetic factors: A family history that makes a person more likely to develop certain conditions.
The Four Major Types of NCDs
According to the World Health Organization (WHO), there are four primary categories of NCDs that account for the vast majority of deaths globally:
- Cardiovascular Diseases: Conditions affecting the heart and blood vessels (e.g., heart attacks and strokes).
- Cancers: The uncontrolled growth and spread of abnormal cells in the body.
- Chronic Respiratory Diseases: Long-term diseases of the airways and other structures of the lungs (e.g., Asthma and Chronic Obstructive Pulmonary Disease).
- Diabetes: A metabolic disease involving elevated blood sugar levels.
The Epidemiological Transition in India
For students of public administration, understanding NCDs is critical. India is currently undergoing an “epidemiological transition.” This means that while the country is successfully controlling infectious diseases (like Polio and Tuberculosis), the burden of lifestyle-related NCDs is rising rapidly. This shift is largely driven by rapid urbanization, changing dietary habits, and increasingly sedentary lifestyles.
Introduction to Genetic Diseases
- Pathogen: Wuchereria (filarial worm)
- Symptoms: Specific to filariasis, including swelling of limbs (lymphedema)
- Transmission: Mosquito bites transmitting larvae to humans
- Note: Mosquitoes act as vectors, transferring larvae to humans during blood meals.
Filarial Worms (Wuchereria):
While lifestyle plays a massive role in NCDs, some diseases are purely determined by our biology from the moment of conception. These are Genetic Diseases.
A genetic disease is caused by an abnormality or a sudden change (mutation) in an individual’s DNA. These diseases are usually hereditary, meaning they are passed down from parents to their children through genes. While we cannot prevent genetic diseases through lifestyle changes or vaccines, scientific advancements and early diagnosis play a crucial role in managing them.
In this chapter, we will study the most critical non-communicable and genetic diseases, their causes, and the public health strategies used to combat them.
