Diseases: Communicable and Non-communicable — Class 10 Health and Physical Education

This chapter explains what diseases are and classifies them as communicable (infectious) and non-communicable. Communicable diseases are caused by germs such as bacteria, viruses, protozoa and fungi, and spread from person to person through air, water, food, contact or insect vectors; examples include the common cold, influenza, tuberculosis, malaria, dengue and diarrhoeal diseases. The chapter describes their causes, modes of spread, symptoms and, most importantly, their prevention through cleanliness, safe water and food, vaccination, control of vectors and good personal hygiene. Non-communicable diseases do not spread from person to person and are often linked to lifestyle and heredity; examples include diabetes, hypertension, heart disease, obesity and cancer. The chapter shows how a healthy lifestyle — balanced diet, regular exercise, avoidance of tobacco and alcohol, and stress management — helps prevent them. It stresses that awareness, hygiene, immunisation and healthy living together protect both the individual and the community from disease.