What is a Disease?
A disease is a particular abnormal condition that negatively affects the structure or function of part or all of an organism. It may be caused by external factors, such as pathogens, or internal dysfunctions.
Types of Diseases
- Infectious Diseases: These are caused by pathogenic microorganisms like bacteria, viruses, parasites, or fungi. Examples include COVID-19, tuberculosis, and malaria.
- Chronic Diseases: These are long-lasting conditions that don’t have a cure but can be managed. Examples include diabetes, heart disease, and cancer.
- Autoimmune Diseases: These occur when the immune system attacks healthy cells by mistake. Examples include rheumatoid arthritis, lupus, and multiple sclerosis.
Case Studies
A study conducted by the World Health Organization (WHO) found that cardiovascular diseases are the leading cause of death globally, accounting for 31% of all deaths. These diseases include heart attacks, strokes, and heart failure.
Another case study by the Centers for Disease Control and Prevention (CDC) revealed that the flu virus infects millions of people each year, leading to hospitalizations and even deaths, especially among vulnerable populations.
Statistics
According to the World Health Organization, an estimated 9.6 million people die each year from cancer, making it the second leading cause of death worldwide. Lung, liver, stomach, colon, and breast cancers are responsible for the most deaths.
Over 400,000 people die from malaria each year, with most deaths occurring in sub-Saharan Africa. The disease is caused by parasites transmitted through mosquito bites.
