Lesson Notes By Weeks and Term v3 - Junior Secondary 2
Non-communicable diseases and their prevention
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Non-communicable diseases and their prevention
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Subject: Physical & Health Education
Class: Junior Secondary 2
Term: 3rd Term
Week: 6
Theme: Basic Human Movement
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define non- communicable diseases. state the nature of non- communicable diseases e.g.- Sickle cell- Obesity- As thma- Anemia- Kwashiorkor, etc.
This section provides in-depth explanations of non-communicable diseases and their nature, focusing on the examples specified in the performance objectives. 2.
1. Definition of Non-Communicable Diseases (NCDs) Non-communicable diseases (NCDs), also known as chronic diseases, are medical conditions that are non-infectious and non-transmissible among people. They are typically of long duration and result from a combination of genetic, physiological, environmental, and behavioural factors. Unlike communicable diseases (e.g., malaria, typhoid), NCDs are not caused by pathogens (like bacteria, viruses, fungi, or parasites) and cannot be "caught" from another person. 2.
2. Nature of Non-Communicable Diseases The nature of NCDs includes: Non-infectious: Not caused by germs or pathogens.
Non-transmissible: Cannot be passed directly from one person to another.
Chronic: They tend to be long-lasting and require ongoing management rather than a quick cure.
Slow Progression: They often develop slowly over a long period, with symptoms appearing gradually.
Multi-factorial Causes: Their development is usually influenced by a combination of genetics, lifestyle choices (diet, exercise, smoking), and environmental factors. 2.
3. Specific Non-Communicable Diseases and Their Nature a.
Sickle Cell Anaemia Nature: A genetic blood disorder that is inherited from both parents. It affects the haemoglobin in red blood cells, causing them to become rigid, sticky, and crescent- or "sickle"-shaped. These sickled cells can block blood flow, leading to pain (sickle cell crises), organ damage, and a shortened lifespan for red blood cells, resulting in anaemia.
Causes: Inherited gene mutation. Individuals inherit two copies of the sickle cell gene (HbSS) to have the disease. Those with one copy (HbAS) have sickle cell trait and are typically healthy carriers.
Symptoms: Severe pain (crises), fatigue, shortness of breath, pale skin, jaundice, delayed growth, frequent infections, swelling of hands and feet.
Relevance in Nigeria: Nigeria has the highest burden of sickle cell disease globally, with millions affected and many more carriers. Understanding this condition is crucial for genetic counselling and community awareness.
Prevention: While the disease itself cannot be prevented in an individual who inherits the genes, its transmission can be prevented through genetic counselling and informed reproductive choices for carriers (HbAS) considering starting families. For those with the disease, management aims to prevent crises and complications through healthy living. b.
Obesity Nature: A complex disease involving excessive body fat accumulation that presents a risk to health. It is not merely about being overweight but having an unhealthy proportion of body fat.
Causes: A combination of factors, primarily: Dietary: High intake of calorie-dense foods, sugary drinks, and processed foods common in Nigerian urban centres.
Lifestyle: Lack of physical activity (sedentary lifestyle), reduced active play for children.
Genetic: Some genetic predispositions.
Environmental: Easy access to unhealthy foods, larger portion sizes, cultural practices that equate weight gain with prosperity.
Symptoms: High Body Mass Index (BMI), large waist circumference, difficulty with physical activity, breathlessness, increased sweating.
Relevance in Nigeria: Increasingly common in Nigeria, particularly in urban areas, due to changing lifestyles, increased consumption of processed foods, and reduced physical activity. It is a major risk factor for other NCDs like diabetes, heart disease, and hypertension.
Prevention: Balanced Diet: Eating a variety of foods, with emphasis on fruits, vegetables, whole grains, and lean proteins, and limiting sugary drinks, fast food, and excessive fried foods.
Regular Physical Activity: Engaging in at least 60 minutes of moderate-to-vigorous physical activity most days of the week (e.g., playing football, dancing, brisk walking, cycling). c.
Asthma Nature: A chronic respiratory condition characterized by inflammation and narrowing of the airways in the lungs, making breathing difficult. It is not contagious.
Causes: A combination of genetic predisposition and environmental triggers.
Triggers: Allergens (dust mites, pollen, pet dander), air irritants (cigarette smoke, exhaust fumes, industrial pollutants, dust from unpaved roads), exercise, cold air, infections, strong emotions.
Symptoms: Wheezing (a whistling sound during breathing), shortness of breath, chest tightness, coughing (especially at night or early morning).
Relevance in Nigeria: Prevalence varies, but it is a significant health concern. Poor indoor air quality from cooking with firewood, vehicular emissions, and industrial pollution in many Nigerian cities can exacerbate asthma. * not contagious.
Causes: A combination of genetic predisposition and environmental triggers.
Triggers: Allergens (dust mites, pollen, pet dander), air irritants (cigarette smoke, exhaust fumes, industrial pollutants, dust from unpaved roads), exercise, cold air, infections, strong emotions.
Symptoms: Wheezing (a whistling sound during breathing), shortness of breath, chest tightness, coughing (especially at night or early morning).
Relevance in Nigeria: Prevalence varies, but it is a significant health concern. Poor indoor air quality from cooking with firewood, vehicular emissions, and industrial pollution in many Nigerian cities can exacerbate asthma.
Prevention: Avoidance of Triggers: Identifying and avoiding specific allergens or irritants that trigger asthma symptoms (e.g., reducing exposure to dust, smoke).
Good Indoor Air Quality: Ensuring proper ventilation, keeping the home clean, and avoiding indoor air pollutants like smoke from cooking or mosquito coils. d.
Anemia Nature: A condition in which the blood lacks healthy red blood cells or haemoglobin. Haemoglobin is the protein in red blood cells that carries oxygen from the lungs to the rest of the body. When there isn't enough haemoglobin, tissues and organs don't get enough oxygen.
Causes: Nutritional Deficiencies: Most commonly iron deficiency (iron-deficiency anaemia), but also deficiencies in folate and Vitamin B
1
2. Blood Loss: Chronic slow bleeding (e.g., from parasitic infections like hookworm, or heavy menstrual periods).
Chronic Diseases: Kidney disease, inflammatory diseases.
Genetic Conditions: Sickle cell anaemia also causes chronic anaemia.
Symptoms: Fatigue, weakness, pale skin, shortness of breath, dizziness, cold hands and feet, headaches.
Relevance in Nigeria: Very common in Nigeria, particularly among children and women of child-bearing age, largely due to malnutrition (iron-poor diets) and high incidence of malaria and parasitic infections that cause blood loss.
Prevention: Balanced Diet Rich in Iron: Consuming iron-rich foods like red meat, poultry, fish, leafy green vegetables (e.g., ugu, spinach, afang), beans, and fortified cereals.
Vitamin C Intake: Eating foods rich in Vitamin C (e.g., oranges, guava, tomatoes, pawpaw) to enhance iron absorption.
Deworming: Regular deworming for children and adults to prevent parasitic infections that cause blood loss. e.
Kwashiorkor Nature: A severe form of protein-energy malnutrition, primarily caused by insufficient protein intake, often in children who have been weaned from breast milk and fed a diet predominantly composed of carbohydrates with inadequate protein.
Causes: Severe protein deficiency in the diet, often occurring in conjunction with insufficient calorie intake, particularly in areas with food insecurity or inadequate dietary knowledge.
Symptoms: Swelling (oedema), particularly in the legs, feet, and face; a distended abdomen (potbelly); stunted growth; thin, sparse, discoloured hair; skin changes (peeling, cracking); irritability; fatigue; weakened immune system.
Relevance in Nigeria: Still observed in parts of Nigeria, especially in rural areas or among low-income populations where access to diverse, protein-rich foods is limited. It highlights the importance of balanced nutrition during early childhood.
Prevention: Adequate Protein Intake: Ensuring children receive a diet rich in protein from sources like eggs, fish, meat, milk, beans, groundnuts, and soy products.
Exclusive Breastfeeding: Promoting exclusive breastfeeding for the first six months of life, followed by continued breastfeeding with appropriate complementary feeding for up to two years or beyond. This section outlines practical activities for the teacher and students to facilitate understanding and engagement.
Teacher Activities: Introduction (5 minutes): Begin by asking students to recall what they learned about communicable diseases (e.g., malaria, typhoid). Introduce the idea that not all diseases are caught from others.
Present the topic: "Non-communicable diseases and their prevention." Definition and Nature of NCDs (10 minutes): Provide a clear definition of non-communicable diseases. Explain the key characteristics (non-infectious, non-transmissible, chronic, slow progression, multi-factorial causes). Engage students by asking them to distinguish NCDs from communicable diseases using simple examples.
Explanation of Specific NCDs (30 minutes): Divide the class into 5 groups (or pairs if the class is small). Assign each group one NCD (Sickle Cell, Obesity, Asthma, Anemia, Kwashiorkor). Provide brief notes or oral instructions on the nature (causes, symptoms) and relevant preventive/management measures for each disease. Circulate among groups, providing guidance and clarifying misconceptions. Group Presentations and Discussion (25 minutes): Have each group present their assigned disease, focusing on its nature (how it affects the body) and general preventive measures. Facilitate a class discussion, inviting questions and contributions from other groups. Correct and elaborate on key points, especially the specific preventive measures for each disease. Emphasize the nuance for sickle cell (genetic counselling for transmission prevention, healthy living for complication management). Use local examples to make the explanations more relatable (e.g., local foods for anaemia, air pollution in Nigerian cities for asthma triggers). Summarization and Reinforcement (5 minutes): Reiterate the definition of NCDs and the importance of their prevention. Emphasize that many NCDs are preventable through lifestyle choices.
Student Activities: Active Listening and Note-taking: Students listen attentively to explanations and take notes on definitions and characteristics of NCDs.
Group Discussion: In their assigned groups, students discuss the nature (causes, symptoms) and potential preventive measures for their assigned NCD, drawing on their knowledge and teacher's guidance.
Group Presentation: Each group presents their findings to the class, describing their assigned NCD and its prevention.
Question and Answer: Students ask questions for clarification and contribute to class discussions.
Reflective Thinking: Students reflect on how these diseases might affect people in their own communities and how they can apply preventive knowledge.
Materials: Whiteboard/Blackboard and markers/chalk Charts or diagrams illustrating the body systems affected by some NCDs (optional) Flashcards with names of NCDs and their key features (optional) Pictures of foods rich in iron or protein (for anaemia and kwashiorkor) The teacher should facilitate these questions after explaining each disease or at key intervals during the lesson to check for understanding.
Question 1: Explain what non-communicable diseases are and give one key characteristic that distinguishes them from communicable diseases.
Solution 1: Non-communicable diseases (NCDs) are medical conditions that are not caused by infectious agents (like bacteria or viruses) and cannot be spread from person to person. A key characteristic that distinguishes them from communicable diseases is that NCDs are non-transmissible (cannot be caught from someone else), whereas communicable diseases are infectious and can be transmitted.
Question 2: Describe the nature of Sickle Cell Anaemia, specifically how it affects the body and how it is acquired.
Solution 2: Sickle Cell Anaemia is a genetic blood disorder, meaning it is inherited from parents. Its nature involves red blood cells, which are normally round, becoming rigid and crescent-shaped (like a sickle). These sickled cells cannot carry oxygen efficiently and can block blood flow in small blood vessels. This leads to symptoms like severe pain, fatigue, and damage to organs over time. It is acquired when an individual inherits a specific gene mutation from both parents.
Question 3: Mention two common causes of obesity in Nigeria and suggest one way to prevent it.
Solution 3: Two common causes of obesity in Nigeria are: Consumption of calorie-dense foods, sugary drinks, and processed snacks. Sedentary lifestyle, which involves little or no physical activity. One way to prevent obesity is to adopt a balanced diet rich in fruits, vegetables, and whole grains, while reducing intake of sugary and fried foods, and engage in regular physical exercise.
Question 4: A child in a Nigerian village frequently looks pale, feels weak, and gets tired easily. Which non-communicable disease could this child be suffering from, and what is one common way to prevent it in the Nigerian context?
Solution 4: Based on the symptoms (paleness, weakness, easy tiredness), the child could be suffering from Anemia. In the Nigerian context, a common way to prevent anemia, especially iron-deficiency anemia, is by ensuring a diet rich in iron-fortified foods, leafy green vegetables, and protein sources, as well as regular deworming to prevent parasitic infections that cause blood loss.
Community Health Campaigns: Students can integrate this knowledge by participating in or initiating local health awareness campaigns in their communities. For example, creating posters or giving short talks during community gatherings about the importance of balanced nutrition to prevent kwashiorkor and anemia, or the benefits of physical activity to combat obesity. This connects directly to public health efforts in Nigeria.
Family Lifestyle Choices: Students can apply their understanding within their families by advocating for healthier eating habits (e.g., encouraging consumption of fruits, vegetables, and lean proteins, and reducing sugary drinks and excessive fried foods) and promoting physical activities suitable for the family (e.g., evening walks, playing local games). This directly impacts the well-being of Nigerian households where dietary and activity patterns are often communal.
Genetic Counselling Awareness: Given the high prevalence of sickle cell disease in Nigeria, students can learn to appreciate the importance of knowing one's genotype before marriage and encourage peers and older relatives to seek genetic counselling. This application is highly relevant to reducing the burden of sickle cell anaemia in future generations in Nigeria.