Transcript Understanding Diseases

Understanding Diseases
Vocabulary
• Epidemic – a widespread occurrence of a disease.
• Bacteria – small, single-celled organisms found
almost everywhere. Millions of beneficial bacteria
live in your body to protect you from harmful
bacteria that cause infection.
• Antibiotic – a drug that kills or slows the growth of
bacteria. Penicillin is the most commonly used
antibiotic
• Virus – an extremely small
particle that consists of an
outer shell and genetic
material. Viruses are not living
organisms – they cannot
reproduce themselves.
• Vaccines – a weak or dead
strain of a virus given to a
healthy person so they can
develop antibodies against a
particular virus
• Immune system – organs and
special cells that fight infection
• Immune response – the
reaction of the body to a germ
that has gotten past the
physical barriers of the defense
system (skin, hairs, tears,
mucus, saliva and stomach acid)
Flu virus
The Immune response – antigens are proteins on the surface of a cell (bacteria,
fungus or virus) that our bodies recognize as foreign invaders
White blood cell
Killer T
Cells ->
Disease = any harmful change in the health of your body
• Infectious Disease is any disease
caused by pathogens that invade the
body
• Pathogen = any organism capable of
producing disease
– Virus – flu (throat, lungs, muscles),
chickenpox (skin), hepatitis (liver)
– Microorganism
• Bacteria – cold (nose, throat, lungs), strep
throat (throat), tuberculosis (lungs)
• Fungi – athlete’s foot (feet), ringworm (skin)
• Protozoa – malaria (carried by mosquitoes)
• Parasite – Lyme’s disease (ticks)
virus
bacteria
A disease which can be passed directly from one
person to another is called a communicable
disease.
• Noninfectious Disease is a disease that is not
caused by a pathogen.
• Cancer – Lymphomas (immune system),
Leukemia (blood), Carcinomas (skin, lungs,
digestive tract), Sarcomas (bones, ligaments
and muscle)
Noninfectious diseases can be inherited, triggered
by something in the environment or be caused by
lifestyle choices (an unhealthy diet can cause Type 2
Diabetes).
• Body System diseases
– Cardiovascular – High blood pressure, clogged arteries, heart
disease, Congenital Heart Defects, Hemophilia
– Respiratory – Allergies, Asthma, Emphysema, Bronchitis,
Pneumonia, Tuberculosis
– Skeletal/Muscular – Muscular Dystrophy, ALS, Osteoporosis,
Scoliosis, Joint injuries, Carpal Tunnel Syndrome, Hernia,
Tendonitis
– Nervous System – Head and Spinal Cord injuries, Parkinson’s
Disease, Multiple Sclerosis, Alzheimer’s disease, Epilepsy, Cerebral
Palsy, Spinal Bifida
– Digestive System – Gallstones, Appendicitis, Lactose Intolerance,
Ulcers, Cirrhosis, Crohn’s Disease, Colitis, Hemorrhoids
Defense Against Disease
• Skin – outer defense
includes also nose hair,
eyebrows and eyelashes
• Mucous Membranes –
mucus is a sticky fluid
that traps pathogens…
they line your mouth,
nose, eyes, throat and
others places.
• Sweat, Saliva and Tears
contain chemicals that kill
bacteria
• Stomach Acid – kills most
of the pathogens found in
food and drink.
• The Immune System –
White blood cells remove
pathogens from your
blood and your Lymphatic
system circulates
antibodies.
Lymphatic System
Prevention and Treatment
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The 5 causes of infectious diseases are…
Viruses
Bacteria
Protozoa and parasites
Fungi
• Most bacterial diseases can be treated with antibiotics
• Antibiotics and other drugs (medicines) are available to
treat most diseases caused by Protozoa and other
parasites.
• Fungi are often treated by antifungal creams and
powders.
• In tropical countries, malaria kills 1-2 million people
every year. It is difficult to stop this disease because it is
impossible to eliminate mosquitoes in some places.
Sleeping under mosquito netting does help prevent
malaria.
Malaria affected areas
• Some ways to control the spread
of disease in your home are…
• Wash your hands
• Keep your kitchen clean
• Don’t share drinking glasses or
eating utensils with someone who
is sick.
• Get treatment if you are sick
before it spreads to others
• If the water supply has harmful
bacteria in it, boiling the water or
treating it with certain chemicals
will help stop the spread of the
bacteria.
Clean water
Dr. Edward Jenner - Vaccines
• 1798 by using pus from a mild disease called cowpox to
inoculate a boy against a deadly disease called smallpox.
• As a doctor, he had noticed that milkmaids who had
recovered from cowpox did not get smallpox… he did not
know what actually caused the disease.
• At the time, smallpox was responsible for about half a
million deaths a year with 20-60% of all those infected –
and over 80% of infected children – dying from the disease.
• In 1979 the World Health Organization certified the
eradication of smallpox and to this day it is the only human
infectious disease to have been completely eradicated.
• Vaccines stimulate your immune system to
produce antibodies which fight invading
pathogens caused by viruses
• Pathogens are all around you. How can you
prevent the spread of common infectious
diseases?
• Get vaccinated
• Avoid direct or indirect contact with other
people when you or they are sick
• Protect yourself against insect bites
• Consume food and water you know is safe
(not contaminated)
• Treat any illness quickly
• Keep your body healthy