Vaccinations and Allergies

1.Active Immunity “actively” producing antibodies to fight infection. Ex: You have a throat infection and you are actively creating antibodies to fight it. 2.Passive Immunity antibodies are given to a person from the blood of another person or animal. This immunity only lasts for a short period of time. ex: Breastfeeding mothers pass antibodies to their children through the milk.

Vaccination A preparation containing antigenic material:  Whole live microorganism  Dead microorganism  Attenuated (harmless) microorganism  Toxoid (harmless form of toxin)  Preparation of harmless antigens Vaccination: An injection of a weakened strain of an infectious microbe (pathogen) that causes the body to undergo active immunity (produce antibodies).

 Immunosuppressed patients  Malnutrition, particularly protein  Allergy to latex or egg

Symptoms:  Red spots containing transparent fluid all over body  Spots filled with pus  Eyelids swell and become glued together

Mortality:  12-30%  Survivors often left blind and disfigured with scars

Eradication:  Started by WHO 1956  Aimed to rid world of smallpox by 1977  Involved aggressive vaccination and surveillance policies  Over 80% of populations at risk of disease were vaccinated  After any reported case, everyone in the household and 30 surrounding houses were vaccinated

 Last case reported in Somalia in 1977  World declared free of smallpox in 1980 Smallpox scars on 10,000BC mummy

Why was eradication successful?  Virus is stable, doesn’t mutate  Cheap vaccine made from harmless strain of similar virus  Vaccine can be used at high temperatures  Easy to identify infected people  Doesn’t lie dormant in body

 Airborne virus  9 th leading cause of death worldwide Symptoms:  Rash and high fever (104⁰)

 Transmitted easily in crowds  Affects malnourished infants with vitamin A deficiency  Can cause severe brain damage, blindness, and sterility  Herd immunity of 93-95% needed to prevent transmission in a population

Allergies When the immune system responds to harmless substances Allergens – antigenic substances which do no real harm Allergens include house dust, animal skin, pollen, house dust mite and its faeces There are two types of allergic reactions. a. Immediate – occurs within seconds and normally lasts for about 30 mins. b. Delayed – takes longer to react and can last for a much longer time.

What happens during an allergic reaction? During an allergic reaction antibodies cause histamines to be released from certain cells. Histamines cause: a. Swelling of tissues b. Release of fluids (runny noses and eyes) c. Muscle spasms (some cases) Example: TB (Mantoux test)

Allergies Histamine causes blood vessels to widen and become leaky. Fluid and white blood cells leave capillaries. The area of leakage becomes hot, red and inflamed

Anaphylaxis or anaphylactic shock: This is the sudden and severe allergic reaction to a substance that can cause death. -inherited tendency to over-produce IgE (evolved to protect against round and flat worm infection) Treatments for Allergies 1.Avoidance of material – especially food. 2.Epinephrine – “epi – pen” 3.Antihistamines -- benadryl

Autoimmune Disease Autoimmune diseases are diseases where the immune system begins to attack itself. ◦Ex: ◦Rheumatoid Arthritis – crippling disease of the joints. ◦Lupus – disease of blood and organs. ◦Multiple Sclerosis – disease of nervous system Cause(s): mostly unknown; virus alters proteins,T cells don’t differentiate properly; a nonself may resemble a self antigen More common in females –fetal cells transport through circulation and cause later response Cures/Treatments: No known cures. Usually treated with drugs.