Maintaining Healthy Systems

The 10 leading causes of death (WHO, 2008) World Deaths in millions % of deaths Ischaemic heart disease % Stroke and other cerebrovascular disease % Lower respiratory infections % Chronic obstructive pulmonary disease % Diarrhoeal diseases % HIV/AIDS % Trachea, bronchus, lung cancers % Tuberculosis % Diabetes mellitus % Road traffic accidents %

Preventive Health Care  The best way to stay healthy is to prevent disease in the first place.  HOW?

 Eat well.

 Avoid unhealthy foods.

 Exercise.

 Make smart choices.

 Rest, wash & immunize.

How does your immune system work? # 1 – Your Skin Skin is a barrier to protect your body against pathogens. Pathogens are disease-causing agents (e.g. bacteria, viruses, fungi, etc.). Enzymes in tears, mucous, and saliva can destroy microbes.

# 2 – In the Respiratory System Mucous and cilia trap debris and pathogens.

# 3. White blood cells Some white blood cells produce pus at the site of an infection when they die. White blood cells engulf microbes, then destroy them with enzymes.

# 4. The Inflammatory Response Swelling, heat and redness due to increased blood flow to the infected area. Fever - increased temperature prevents viruses from reproducing as fast.

# 5. The Immune Response Pathogens have proteins on their surface called antigens. Some white blood cells make proteins called antibodies that attach to antigens to help destroy the pathogens.

Allergies Allergic reactions occur when your body recognizes the antigens on allergens as dangerous, and tries to fight them.

What are vaccines?  antigen-containing substances obtained from weakened or dead microbes Jenner, 1796 smallpox

Pasteur, 1885 rabies

Salk, 1955 polio

What are antibiotics?  chemical agents that are toxic to bacteria Fleming, 1928

 Colds and flu are caused by viruses, so antibiotics are useless against them.

Organ Transplantation  What organs and tissues can be donated?  How many people in Ontario are waiting for organ transplants?  How is living donation different from organ donation after cardiac death (DCD)?