Lesson Notes By Weeks and Term v3 - Senior Secondary 1
Communicable diseases
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Communicable diseases
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Subject: Health Education
Class: Senior Secondary 1
Term: 3rd Term
Week: 2
Theme: Communicable And Non Communicable Diseases
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define the term communicable disease, epidemiology, prevalence rate. list and classify communicable diseases according to mode of transmission.
Communicable And Non Communicable Diseases Grade / Level: Senior Secondary 1 Subject: Health Education Topic: Communicable diseases Term: 3rd Term Week: 31 ---
1. Overview and Learning Objectives This topic introduces students to the fundamental concepts of communicable diseases, which are a significant public health concern in Nigeria. Understanding these diseases is crucial for promoting personal hygiene, community health, and informed decision-making regarding disease prevention and control. Students will learn how these diseases spread and the methods used to track their occurrence within populations. This knowledge empowers them to take proactive steps to protect themselves and their communities from various infections, thereby contributing to a healthier society and workforce. By the end of this lesson, students will be able to: Define what a communicable disease is, along with related terms like epidemiology and prevalence rate. Identify and categorize different communicable diseases based on how they are transmitted from one person or organism to another. Apply this knowledge to understand common disease patterns in Nigeria and contribute to their prevention and control efforts.
2. Key Concepts and Explanations
A. Definitions Communicable Disease: A disease that can be transmitted directly or indirectly from one host to another. These diseases are caused by infectious agents (pathogens) such as bacteria, viruses, fungi, or parasites. Examples common in Nigeria include malaria, typhoid fever, cholera, measles, tuberculosis, and HIV/AID
S. Characteristics: Caused by specific pathogens. Can spread from an infected person or animal to a healthy one, or from the environment. Often preventable through hygiene, vaccination, or vector control.
Epidemiology: The study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems. In simpler terms, it is the science of understanding how diseases spread through populations and what factors influence their occurrence.
Importance: Epidemiology helps public health officials in Nigeria: Track disease outbreaks (e.g., Lassa fever, Cholera). Identify risk factors for diseases. Develop effective prevention and control strategies (e.g., vaccination campaigns, sanitation improvements). Evaluate the effectiveness of health interventions.
Prevalence Rate: A measure of the total number of existing cases of a disease (or a health condition) in a population at a specific point in time or over a period. It indicates the burden of disease in a community.
Formula: Prevalence Rate = (Number of existing cases of a disease at a specified time / Total population at that specified time) × K Where K is a constant (e.g., 100 to express as a percentage, 1,000 to express per 1,000 population, or 100,000 for rare diseases). For SS1, expressing per 1,000 or as a percentage is usually sufficient.
Worked Example (Nigerian Context): A health survey in a rural community in Cross River State with a population of 5,000 people identified 250 existing cases of typhoid fever during the month of July. Calculate the period prevalence rate of typhoid fever per 1,000 population for that month.
Solution: Number of existing cases = 250 Total population = 5,000 K = 1,000 (to express per 1,000 population) Prevalence Rate = (250 / 5,000) × 1,000 Prevalence Rate = 0.05 × 1,000 Prevalence Rate = 50 cases per 1,000 population.
Interpretation: This means that for every 1,000 people in that community during July, 50 had typhoid fever. B. Classification of Communicable Diseases According to Mode of Transmission Communicable diseases can be classified based on how the infectious agent travels from the source to a susceptible host.
1. Direct Contact Transmission: Occurs when there is physical contact between an infected person/animal and a susceptible person.
Examples: Skin-to-skin contact, kissing, sexual contact. Nigerian
Examples: Sexually Transmitted Infections (STIs): HIV/AIDS, Syphilis, Gonorrhea, Chlamydia.
Skin Infections: Scabies, Ringworm (from direct contact with infected person or contaminated items).
Lassa Fever: Can be transmitted person-to-person through direct contact with infected bodily fluids.
2. Indirect Contact Transmission: Occurs when an infectious agent is transferred via an inanimate object (fomite) or through droplets or airborne particles.
Sub-types: Fomite-borne: Through contaminated objects like doorknobs, toys, clothing, utensils, hospital equipment.
Nigerian and Answer: Ask targeted questions throughout the lesson to gauge understanding of definitions and classification.
Activity Review: Assess the accuracy of disease classification during group presentations.
B. Summative Assessment (End of Lesson/Week): Question: List three examples each of communicable and non-communicable diseases.
Marking Scheme: Communicable Diseases (3 marks): 1 mark for each correct example of a communicable disease (e.g., Malaria, Typhoid, Cholera, Measles, Tuberculosis, HIV/AIDS, Hepatitis, Lassa fever, Yellow fever, Whooping cough, etc.). Maximum of 3 marks.
Non-communicable Diseases (3 marks): 1 mark for each correct example of a non-communicable disease (e.g., Diabetes, Hypertension/High Blood Pressure, Asthma, Cancer, Sickle Cell Anemia, Arthritis, Heart disease, Stroke, etc.). Maximum of 3 marks.
Total: 6 marks.
7. Real-life Applications / Integration
1. Community Health Campaigns: The understanding of communicable disease transmission modes directly informs the design of public health campaigns in Nigeria. For instance, knowing malaria is vector-borne (mosquitoes) leads to campaigns for insecticide-treated nets and environmental sanitation (clearing stagnant water). Knowledge of vehicle-borne diseases (cholera, typhoid) drives campaigns for safe drinking water, proper food hygiene, and sanitation facilities (e.g., 'WASH' programs).
2. Personal Hygiene and Sanitation: Students can apply the knowledge of direct and indirect contact transmission to personal practices. This includes regular handwashing, avoiding sharing personal items, covering coughs and sneezes, and practicing safe sex to prevent STIs. This directly impacts their health and that of their families, especially in crowded Nigerian urban or rural settings.
3. Epidemiological Surveillance and Response: In Nigeria, agencies like the Nigeria Centre for Disease Control (NCDC) actively use epidemiological principles to track disease outbreaks (e.g., Lassa fever, Cholera, COVID-19). Students' understanding of prevalence rates and transmission helps them appreciate why government and health agencies collect data, conduct contact tracing, and implement measures like vaccination drives or quarantines to protect the population and economy.
8. Differentiation, Remediation and Extension
A. Differentiation Strategies (General)
Visual Aids: Use charts, diagrams, and pictures depicting disease transmission cycles (e.g., malaria life cycle, cholera transmission) for visual learners.
Group Work: Organize students into mixed-ability groups to encourage peer learning and support, allowing stronger students to explain concepts to weaker ones.
Varied Questioning: Employ a range of questions from recall to higher-order thinking to cater to different cognitive levels.
B. Remediation (For Struggling Learners)
Simplified Explanations: Provide one-on-one or small-group re-explanation of core definitions (communicable disease, epidemiology, prevalence rate) using simpler language and more concrete, local examples.
Visual Cues and Mnemonics: Use memorable acronyms or simple drawings to help recall different modes of transmission and their examples.
Flashcards: Provide flashcards with disease names on one side and their mode of transmission on the other for self-study and peer quizzing.
Focused Practice: Offer additional, simpler guided practice questions primarily focusing on identifying key terms and direct association of diseases with transmission modes.
C. Extension (For High-Achieving Learners)
Research Project: Task students to research a specific communicable disease outbreak that occurred in Nigeria (e.g., Ebola, Lassa fever, Cholera) and prepare a brief presentation or report on its epidemiology, mode of transmission, and the control measures implemented.
Public Health Campaign Design: Challenge students to design a mini-public health awareness campaign poster or jingle targeting a specific communicable disease prevalent in their local community, detailing prevention strategies based on its mode of transmission. Data Analysis*: Provide a hypothetical dataset (e.g., number of reported malaria cases over a year in different age groups or local government areas) and ask them to calculate prevalence trends and suggest possible contributing factors or interventions. specific Nigerian examples.
Facilitates a brainstorming session: Divides the class into small groups (3-4 students). Assigns each group one mode of transmission and instructs them to list as many Nigerian diseases as they can for their assigned mode, beyond those already mentioned. Circulates to assist groups and clarify misconceptions.
Student Activity: Students listen attentively and take notes on each mode of transmission and its examples. In groups, students discuss and brainstorm diseases that fit their assigned mode of transmission. Each group presents its findings to the class.
C. Conclusion (5 minutes)
Teacher Activity: Recaps the main definitions (communicable disease, epidemiology, prevalence rate) and the five modes of transmission with key examples. Addresses any lingering questions from students.
Student Activity: Students listen to the summary and ask any final questions.
4. Guided Practice (With Solutions)
1. Question: Explain the term "communicable disease" and give two examples common in Nigeria.
Solution: A communicable disease is an illness caused by an infectious agent (like bacteria, viruses, or parasites) that can be transmitted directly or indirectly from an infected host to a susceptible host.
Examples in Nigeria: Malaria, Typhoid fever, Cholera, Measles, HIV/AIDS (any two acceptable).
Commentary: This question assesses the basic understanding of the core concept of the lesson.
2. Question: In a village of 1,200 people, a recent health screening revealed 60 individuals currently living with Hepatitis
B. Calculate the prevalence rate of Hepatitis B per 1,000 population in this village.
Solution: Number of existing cases = 60 Total population = 1,200 Prevalence Rate = (60 / 1,200) × 1,000 Prevalence Rate = 0.05 × 1,000 Prevalence Rate = 50 cases per 1,000 population.
Commentary: This tests the ability to apply the prevalence rate formula in a practical scenario, relevant to public health data.
3. Question: Give one example of a communicable disease transmitted by each of the following modes, specifically mentioning a disease prevalent in Nigeria: a. Vector-borne b. Direct contact c.
Vehicle-borne (food/water)
Solution: a.
Vector-borne: Malaria (transmitted by Anopheles mosquito) OR Yellow Fever (transmitted by Aedes aegypti mosquito). b.
Direct contact: HIV/AIDS (sexual contact) OR Scabies (skin-to-skin contact). c.
Vehicle-borne (food/water): Cholera (contaminated water/food) OR Typhoid fever (contaminated water/food).
Commentary: This question evaluates the understanding of different transmission modes and the ability to recall specific Nigerian examples for each.
5. Independent Practice (Questions Only)
1. Define epidemiology in your own words.
2. State the key difference between airborne and droplet transmission, giving one Nigerian example for each.
3. Imagine a town with a population of 15,000 people. A recent clinic report showed 750 cases of tuberculosis (TB) currently being managed. Calculate the prevalence rate of TB as a percentage in this town.
4. List two communicable diseases that can be transmitted directly through sexual contact.
5. Explain how improper waste disposal can lead to the spread of vehicle-borne diseases in a community.
6. Identify the mode of transmission for the following diseases: a. Measles b. Cholera c. Sleeping sickness d. Gonorrhea
7. Suggest three practical ways individuals can prevent the spread of communicable diseases in their homes and schools.
8. Why is it important for a country like Nigeria to have a good understanding of epidemiology?
9. Provide three examples of non-communicable diseases. (Teacher's note: This question addresses the evaluation guide and assumes prior knowledge or general understanding of non-communicable diseases for comparative purposes, though the lesson focused on communicable.)
6. Evaluation and Assessment
A. Formative Assessment: Observation: Monitor student engagement during group activities and discussions.
Question and Answer: Ask targeted questions throughout the lesson to gauge understanding of definitions and classification.
Activity Review: Assess the accuracy of disease classification during group presentations.
B. Summative Assessment (End of Lesson/Week): Question: List three examples each of communicable and non-communicable diseases.
Marking Scheme: Communicable Diseases (3 marks): 1 mark for each correct example of a communicable disease (e.g., Malaria, Typhoid, Cholera, Measles, Tuberculosis, HIV/AIDS, Hepatitis, Lassa fever, Yellow fever, Whooping cough, etc.). Maximum of 3 marks.
Non-communicable Diseases (3 marks): 1 mark for infected person/animal and a susceptible person.
Examples: Skin-to-skin contact, kissing, sexual contact. Nigerian
Examples: Sexually Transmitted Infections (STIs): HIV/AIDS, Syphilis, Gonorrhea, Chlamydia.
Skin Infections: Scabies, Ringworm (from direct contact with infected person or contaminated items).
Lassa Fever: Can be transmitted person-to-person through direct contact with infected bodily fluids.
2. Indirect Contact Transmission: Occurs when an infectious agent is transferred via an inanimate object (fomite) or through droplets or airborne particles.
Sub-types: Fomite-borne: Through contaminated objects like doorknobs, toys, clothing, utensils, hospital equipment. Nigerian
Examples: Common cold (e.g., touching a contaminated surface then touching one's face), Conjunctivitis (pink eye) from shared towels.
Droplet Transmission: Occurs when droplets (larger particles from coughs, sneezes, talking) carrying infectious agents travel short distances (usually less than 1-2 meters) and land on mucous membranes of a susceptible host. Nigerian
Examples: Common cold, Influenza, Whooping cough, Meningitis (bacterial type).
Airborne Transmission: Occurs when infectious agents remain suspended in the air over long distances (more than 2 meters) and time, often in the form of droplet nuclei (tiny particles that evaporate from larger droplets). Nigerian
Examples: Measles, Chickenpox, Tuberculosis (TB).
3. Vector-borne Transmission: Occurs when an infectious agent is transmitted between hosts by a living organism (a vector), usually an arthropod (like mosquitoes, ticks, flies). Nigerian
Examples: Mosquitoes: Malaria (Anopheles mosquito), Yellow Fever (Aedes aegypti), Dengue Fever (Aedes aegypti).
Tsetse Fly: African Trypanosomiasis (Sleeping sickness).
Black Fly: Onchocerciasis (River blindness).
Rats/Rodents: Lassa fever (multimammate rat – primary reservoir, but can spread via direct contact as well).
4. Vehicle-borne Transmission: Occurs when an infectious agent is transmitted through contaminated inanimate vehicles such as food, water, milk, or biological products (e.g., blood). Nigerian
Examples: Contaminated Water/Food: Cholera, Typhoid fever, Dysentery, Hepatitis A, Food poisoning (e.g., from Salmonella, E. coli). These are prevalent where water and food sanitation are poor.
5. Perinatal (Vertical)
Transmission: Transmission of a disease from mother to child during pregnancy, childbirth, or breastfeeding. Nigerian
Examples: HIV/AIDS Syphilis Hepatitis B Rubella
3. Teaching and Learning Activities
A. Introduction (10 minutes)
Teacher Activity: The teacher initiates a brief discussion by asking students to name common diseases they know or have heard of in their communities. The teacher lists these on the board and subtly guides them to distinguish between those that spread easily and those that don't.
Student Activity: Students respond by naming diseases like malaria, cough, cholera, diabetes, high blood pressure. They attempt to categorize them based on observed spread.
B. Lesson Development (35 minutes)
Activity 1: Defining Communicable Diseases, Epidemiology, and Prevalence Rate (15 minutes)
Teacher Activity: Presents the definition of "communicable disease," providing examples relevant to Nigeria (e.g., malaria, typhoid, measles). Emphasizes the concept of 'spread'. Explains "epidemiology" as the study of disease patterns, using examples of how health workers investigate outbreaks in Nigeria. Defines "prevalence rate" and explains its significance. Writes the formula on the board and demonstrates the worked example provided in Key Concepts and Explanations (typhoid fever in Cross River State). Engages students in a quick Q&A to check understanding.
Student Activity: Students actively listen, take notes, and ask clarifying questions. They attempt to solve the prevalence rate example with the teacher's guidance.
Activity 2: Classifying Communicable Diseases by Mode of Transmission (20 minutes)
Teacher Activity: Introduces the various modes of transmission (Direct Contact, Indirect Contact, Vector-borne, Vehicle-borne, Perinatal). For each mode, the teacher explains the mechanism and provides 2-3 specific Nigerian examples.
Facilitates a brainstorming session: Divides the class into small groups (3-4 students). Assigns each group one mode of transmission and instructs them to list as many Nigerian diseases as they can for their assigned mode, beyond those already mentioned. Circulates to assist groups and clarify misconceptions.
Student Activity: Students listen attentively and take notes on each mode of transmission and its examples. In groups, students discuss and brainstorm diseases that fit their assigned mode of transmission. * Each group presents its findings to the