Section E

1. Define: Good Health vs Disease
Good Health (WHO Definition):

A state of complete physical, mental and social well-being, not just the absence of disease or infirmity.
Disease:

A condition that negatively affects the normal functioning of the body or mind. Can be caused by pathogens, genetics, environment, or lifestyle.

2. Classify Diseases
Communicable (Infectious) Diseases
→ Can be spread from person to person.
E.g. flu, cholera, HIV/AIDS

Non-Communicable Diseases (NCDs)
→ Cannot spread from person to person.

Chronic or degenerative: diabetes, heart disease
Nutritional deficiency: scurvy, kwashiorkor
Inherited disorders: sickle cell anaemia, haemophilia

3. Signs vs Symptoms
Signs = What can be seen or measured (objective)
e.g. fever, rash, swelling
Symptoms = What the patient feels (subjective)
e.g. pain, fatigue, dizziness

4. Asthma: Cause, Symptoms, Treatment
Cause: Allergens (dust, pollen), cold air, exercise, stress
Primary Symptoms: Shortness of breath, wheezing, chest tightness, coughing
Treatment:

Inhalers (bronchodilators)
Avoid triggers
Anti-inflammatory meds

5. How Asthma Affects the Respiratory Tract
Airways become inflamed and narrow
Muscles around airways tighten
Mucus builds up, making it hard to breathe
→ Results in coughing, wheezing, and difficulty breathing

6. Chronic/Lifestyle Diseases: Causes, Signs, Treatment, Prevention
(a) Obesity
Cause: Overeating, poor diet, lack of exercise
Signs/Symptoms: High body fat, fatigue, joint pain
Treatment: Balanced diet, exercise, weight loss meds/surgery
Prevention: Healthy eating, regular physical activity
Diabetes Mellitus (Type I & II)
Type I:

Cause: Autoimmune—body destroys insulin-producing cells
Signs: Frequent urination, thirst, weight loss
Treatment: Insulin injections
Type II:

Cause: Insulin resistance, often linked to obesity
Signs: Same as Type I, often milder at first
Treatment: Diet, exercise, meds like Metformin
Prevention (Type II): Stay active, eat balanced meals
Cardiovascular Diseases
Hypertension:

Cause: High salt intake, stress, lack of exercise
Signs: Often no symptoms, or headaches/dizziness
Treatment: Low-sodium diet, meds, stress control
Coronary Heart Disease (CHD):

Cause: Fatty deposits in heart arteries
Signs: Chest pain, breathlessness
Treatment: Surgery (bypass), meds, lifestyle changes
(b) Obesity ➝ Type II Diabetes & Secondary Hypertension
Excess weight leads to insulin resistance and extra pressure on the heart.
Fixing weight can lower the risk or help reverse early-stage conditions.
(c) Importance of Diet & Exercise
Keeps body systems working properly.
Reduces risk of obesity, diabetes, heart disease.
Boosts mood and energy levels.

7.

8. HIV/AIDS
Cause: Human Immunodeficiency Virus (HIV)
Transmission:

Unprotected sex
Sharing needles
Mother to baby
Blood transfusion
Symptoms: Fever, weight loss, night sweats, infections
Prevention: Safe sex, regular testing, avoid sharing needles
Treatment:

Antiretroviral (ARV) drugs (suppress virus)
Side effects: nausea, tiredness, liver issues

9. STIs in Pregnancy
STIs like syphilis, HIV, herpes can:

Cause miscarriage, premature birth, stillbirth
Be passed to baby during birth (congenital diseases)
Prevention: Testing during pregnancy + early treatment

10. Impact of Diseases on Human Population
Social: Stigma, isolation, family stress
Economic: Healthcare costs, job loss, lower productivity
Community: School dropouts, reduced workforce, increased poverty

11. Malaria & Dengue (Strain I–IV)
Malaria
Cause: Plasmodium parasite (spread by female Anopheles mosquito)
Symptoms: Fever, chills, sweating, vomiting, headache
Transmission: Mosquito bite
Prevention: Mosquito nets, repellents, draining stagnant water
Treatment: Antimalarial drugs like chloroquine or artemisinin
Dengue
Cause: Dengue virus (spread by Aedes aegypti mosquito)
Symptoms: High fever, muscle/joint pain, rash, bleeding
Transmission: Mosquito bite
Prevention: Same as malaria — eliminate mosquito breeding sites
Treatment: No cure — supportive care like fluids, painkillers (no aspirin)

12. Vectors and Human Health
Vectors = animals that spread diseases without getting sick
Vector
Disease
Mode of Action
Rats
Leptospirosis, plague
Bite or contaminated food/urine
Mosquitoes
Dengue, malaria, Zika
Bite to transmit pathogens
Houseflies
Gastroenteritis, cholera
Land on food with dirty feet, spread bacteria

13. Life Cycle of Mosquito & Housefly
Mosquito Life Cycle:
Egg (on water)
Larva (wiggler)
Pupa (tumbler)
Adult mosquito
➡ Happens in water! That's why we drain it.
Housefly Life Cycle:
Egg (laid on garbage/rotting stuff)
Larva (maggot)
Pupa
Adult fly
➡ They lay eggs in filth, then crawl on your food 🤢


14. Vector Control: Why & How
Why Control Vectors?
They spread deadly diseases like malaria, dengue, leptospirosis, and gastroenteritis.
How to Control Them:
Eliminate breeding sites (stagnant water, garbage)
Use insecticides/repellents
Mosquito nets and screens
Personal hygiene + waste management

15. Personal Hygiene
Why Maintain It?
Avoid body odour
Prevent infections (like UTIs, skin rashes)
Gain social acceptance
Avoid dental issues (like cavities)
How To Maintain It:
Bathe regularly
Brush teeth twice a day
Clean genitals properly (circumcision may reduce risk of some infections)
Wash hands after bathroom and before eating

16. Controlling Microorganism Growth
(a) Sterilization (Kills all microbes)
Definition: Killing/removing all microorganisms
Methods:

UHT (Ultra High Temp): Milk
Pasteurization: Partial heating to kill bacteria
Autoclaving: High pressure steam
Boiling
Canning: Heat + sealed container
(b) Other Methods
Disinfectants: Kill bacteria on surfaces (e.g. bleach)
Antiseptics: Safe for skin (e.g. hydrogen peroxide)
High temp: Kills most bacteria
(c) Difference
Disinfectant = For surfaces
Antiseptic = For living tissue (your skin)

17. Disinfectants vs Antiseptics
Type
Used On
Purpose
Example
Disinfectant
Non-living things (surfaces)
Kill germs on surfaces
Bleach, Lysol
Antiseptic
Living tissue (skin)
Kill/inhibit germs on skin
Hydrogen peroxide, Dettol

18. Antibiotics & Antifungals
Antibiotics: Kill or stop bacteria (e.g. penicillin) — don’t work on viruses.
Antifungals: Fight fungal infections (e.g. athlete’s foot)
Key terms:

Antigen: Any foreign substance that triggers immune response.
Antibody: Protein made by the body to attack antigens.
Antitoxin: Neutralizes toxins made by bacteria (like in tetanus).

19. Types of Immunity
Type
Source
Natural Active
Get sick, body makes antibodies
Natural Passive
Antibodies from mother (placenta/breast milk)
Artificial Active
Vaccine (makes you build immunity)
Artificial Passive
Injection of antibodies (e.g. after a bite)

20. Immunity vs Immunization
Immunity: Ability to resist infection.
Immunization: The process of becoming immune (often through vaccination).
Vaccine: Substance used to trigger immune response.
Vaccination: Act of giving the vaccine.

21. Drug Use & Misuse
Prescription Drugs:
Sedatives, painkillers, antibiotics
Can lead to dependence if misused
Non-Prescription/Illegal Drugs:
Cocaine, LSD, heroin, ecstasy, marijuana, alcohol
Can cause:

Psychological effects: Anxiety, hallucinations
Physiological effects: Organ damage, addiction

22. Social Effects of Drug Misuse
Individual: Health decline, mental breakdown, financial issues
Family: Broken relationships, abuse, neglect
Community: Crime, reduced productivity, healthcare strain
➡ You might have to analyze charts or data showing these impacts

23. Representing Data
You'll need to interpret or create:

Tables
Bar graphs
Line graphs
Pie charts
These could show:

Disease rates over time
Effects of vaccines
Hospital admissions
Drug abuse stats