Pathogens, Diseases, and Their Prevention – JSS1 Physical & Health Education Lesson Note (Second Term)

A pathogen is an agent that causes disease when it enters the body. Pathogens include viruses, bacteria, fungi, protozoa, worms and rickettsiae. A disease is a condition that disrupts the structure and function of the body system. Diseases are either communicable or non-communicable, and communicable diseases can be prevented and controlled in several ways.

Behavioural objectives

By the end of the lesson, students should be able to:

• define pathogens and disease;
• list the types of pathogens;
• name some diseases caused by pathogens;
• differentiate between communicable and non-communicable diseases, with examples;
• state ways of preventing and controlling communicable diseases.

What are pathogens?

Pathogens are very tiny organisms that cannot be seen with the naked eye but which cause diseases when they enter the body. The agents causing diseases are called pathogens.

Types of pathogens

Pathogens, or disease-causative agents, are the following:

1. Viruses
2. Bacteria
3. Fungi
4. Protozoa
5. Worms
6. Rickettsiae

What is a disease?

A disease is a condition that disrupts the structure and function of the body system.

Diseases caused by pathogens

The diseases which are caused by pathogens are also known as pathogenic diseases. Examples are:

1. Diarrhoea
2. Poliomyelitis
3. Tuberculosis
4. Hepatitis
5. HIV/AIDS
6. Malaria
7. Measles
8. Chickenpox
9. Mumps

Types of diseases

There are two main types of diseases:

1. Communicable diseases
2. Non-communicable diseases

What are communicable diseases?

Communicable diseases can be transmitted from one person to another or from animals to humans. Some common examples are:

1. Whooping cough
2. Measles
3. HIV/AIDS
4. Tuberculosis
5. Yellow fever
6. Cholera
7. Syphilis
8. Scabies
9. Flu
10. Gonorrhoea

What are non-communicable diseases?

Non-communicable diseases cannot be transmitted from one person to another. They may result from physiological failure, chemical fallout, malnutrition, genetic traits, brain damage and similar causes. Examples are:

1. Cancer
2. Stroke
3. Asthma
4. Sickle cell
5. Ulcer
6. Kwashiorkor
7. Epilepsy
8. Neurosis
9. Marasmus
10. Hypertension

How can communicable diseases be prevented and controlled?

Communicable diseases can be prevented and controlled through:

1. Health education
2. Immunisation
3. A clean environment
4. Adequate nutrition and feeding
5. Isolation and quarantine
6. Regular exercise
7. Good personal hygiene

Evaluation

1. What are diseases and pathogens?
2. Differentiate between communicable and non-communicable diseases, with examples.
3. State three ways of preventing diseases.

Assignment

Give five ways of preventing communicable diseases.