Principles of Immunisation & Disease Control

Principles of Immunisation in the Control of Communicable/Infectious Diseases

• The immune system defends the body against pathogens, including white blood cells, antibodies, and the lymphatic system
• Diseases can weaken the immune system by attacking immune cells or interfering with their function
• HIV/AIDS weakens the immune system by attacking white blood cells, making it harder to fight infections
• Immunity is the body's ability to resist disease by recognizing and destroying harmful microorganisms

Role of White Blood Cells

• White blood cells (WBCs) protect the body by identifying and attacking pathogens
• WBCs produce antibodies to fight infections
• White blood cells remember past infections to provide long-term immunity

Types of Immunity

• Natural immunity protects the body without medical intervention
• Innate immunity is the immunity someone is born with
• Acquired immunity develops after recovering from an infection
• Artificial immunity is protection developed through medical intervention, like vaccination
• Vaccines contain weakened or dead pathogens, which help the body produce antibodies
• The Covid-19 and Polio vaccines train the immune system to recognize and destroy these viruses

Non-Communicable/Infectious Diseases

• A non-infectious disease cannot be spread from person to person
• Non-infectious diseases are caused by factors such as genetics, lifestyle, or environmental conditions, e.g., Diabetes and Hypertension

Examples of Non-Infectious Diseases

• An allergy is when the immune system overreacts to a normally harmless substance (allergen) like dust, pollen, or certain foods
• Allergy symptoms are sneezing, itching, rashes, and swelling
• Autoimmune diseases occur when the immune system mistakenly attacks healthy body cells
• Lupus affects the skin, joints, and organs, causing inflammation and pain
• Rheumatoid arthritis affects the joints, causing swelling, stiffness, and pain

Diabetes and Hypertension: Causes and Effects

• Diabetes is a disease where the body cannot regulate blood sugar properly
• Type 1 diabetes' cause is lack of insulin, and Type 2 diabetes' cause is insulin resistance
• Effects of diabetes are nerve damage, kidney problems, and vision loss
• Hypertension (High Blood Pressure) occurs when blood pressure is too high
• Causes of high blood pressure are poor diet, stress, lack of exercise, and genetics
• Effects of high blood pressure are heart disease, kidney failure, and stroke

Communicable/Infectious Diseases

• A disease is an illness that affects the normal functioning of the body
• A communicable (infectious) disease can spread from one person to another through direct contact, air, water, or contaminated surfaces

Information about Specific STIs

• Syphilis is a bacterial STI caused by Treponema pallidum, with symptoms including sores, rashes, and fever; use safe sex and regular testing to prevent it; treatable with antibiotics
• Gonorrhea is a bacterial STI caused by Neisseria gonorrhoeae, with symptoms including painful urination and discharge; use safe sex and regular testing to prevent it; treatable with antibiotics
• Chlamydia is a bacterial STI caused by Chlamydia trachomatis, with symptoms including painful urination and discharge; use safe sex and regular testing to prevent it; treatable with antibiotics
• Herpes is a viral STI caused by Herpes simplex, with symptoms including blisters, pain, and itching; avoid direct contact to prevent it; there is no cure but antiviral drugs can provide treatment
• Hepatitis B & C are viral STIs caused by Hepatitis viruses, with symptoms including jaundice and liver damage; vaccination and hygiene can prevent it; there is no cure but antiviral drugs can provide treatment
• HIV/AIDS is a viral STI caused by Human Immunodeficiency Virus, with symptoms including a weak immune system and weight loss; use safe sex and avoid sharing needles to prevent it; there is no cure but ART (Antiretroviral Therapy) helps in treatment
• Candidiasis (Thrush) is a fungal STI caused by Candida, with symptoms including white patches in the mouth and itching; hygiene and a healthy diet can prevent it; antifungal medication can treat it