Transcript Preventing Communicable Diseases

Preventing Communicable
Diseases




Immune System – a network of cells, tissues,
organs, and chemicals that fight pathogens.
First line of Defense- Physical and Chemical:
skin, mucous membranes, cilia
enzymes in tears, saliva, gastric juices
Inflammatory Response




A reaction to tissue damage caused by injury or
infection. (hot, swollen, red, painful)
Release of Phagocytes – a white blood cell that
attacks invading pathogens.
(Pus- a collection of dead white blood cells and
damaged tissues)
Repair now begins at injured site.
Specific Defenses


When certain pathogens enter the body, the
body’s immune response will recognize this
pathogen and send out specific antigens- a
substance that is capable of triggering an
immune response.
This response is what we call immunity – the
state of being protected against a certain disease.
Battling Specific Diseases





Lymphocyte- a specialized white blood cell that
coordinates and performs many of the functions of
specific immunity.
Two Types – “T” cells and “B” cells
(Helper “T” cells, Killer “T” cells, Suppressor “T” cells)
“B” cells produce antibodies – a protein that acts
against a specific antigen.
An antibody will either mark a cell for destruction,
destroy the antigen or block the virus from entering the
body.
Memory Lymphocytes



Some “B” and “T” cells actually have a memory
and circulate through the body looking for
“bad” invaders who have been there before- if
found, they begin the attack to prevent illnesses.
Active immunity- developed by your body
Artificial immunity- vaccine- a preparation of
dead or weakened pathogens that are introduced
into the body to stimulate an immune response.
Vaccines




Live virus vaccines – made from pathogens grown
under special lab conditions to make them lose most of
their disease causing properties. (measles, mumps,
rubella, chicken pox)
Killed virus vaccines – inactivated pathogens. Still cause
an immune response and antibodies are produced. (flu
shots, polio, rabies, hepatitis A)
Toxoids – inactivated toxins from pathogens (tetanus,
diptheria) used to stimulate production of antibodies.
New and second generation vaccines- developed by
scientists using new technologies. (hepatitus B)
Common Communicable Diseases






Respiratory Infections (URI)
most caused by viruses and bacteria
avoid contact with infected people
smoking can reduce chances of fighting uri’s
Common Cold- runny nose, sneezing, sore throat, headache
Influenza- fever, chills, dry cough, joint pain, runny nose, sore throat,
extreme fatigue

Pneumonia- an infection of the lungs in which the air
sacs fill with pus and other liquids.

Strep Throat –(bacterial infection) sore throat, fever, enlarged lymph
nodes. Treated with antibiotics.

Tuberculosis – (Bacterial) attacks the lungs.
fatigue, coughing
(blood), fever, night sweats, and weight loss.




Hepatitis- inflammation of the liver.
Caused by chemicals and many
other pathogens. No cure – but vaccines for A and B.
“A” – spread through contact with feces of an infected person. Not
washing hands properly before handling objects or food.
Jaundice- yellowing of skin and eyes.

“B” – more serious than “A”. Found in most bodily fluids, especially
blood. Transmitted sexually. Drug use, piercings, tatoos, etc.

“C” – most common, transmitted by direct contact with infected blood.

Other Common Diseases

Mononucleosis- virus, spread by direct contact sharing utensils,
kissing- “kissing disease”. Chills, fever, sore throat, fatigue and swollen lymph
nodes.

Measles – virus, spread by coughs, sneeze, close contact-highly
contagious. Fever, red eyes, runny nose, cough, bumpy red rash.

Encephalitis – virus, transmitted by mosquitoes. Causing swelling of
the brain. Headaches, fever, hallucinations, confusion, paralysis.

Meningitis – Virus or bacteria cause inflammation of the membranes
that cover the brain. Fever, headache, nausea, vomiting, stiff neck
Emerging Diseases

Emerging infections –communicable diseases
whose occurrence in humans has increased
within the past two decades or threatens to
increase in the future.

Avian Influenza- “Bird Flu”
(direct contact with infected birds or
contaminated surfaces. No vaccine, no cure.




H1N1 Virus- respiratory virus normally found
in pigs. Symptoms- fever, sore throat, runny
nose, body aches, and fatigue.
Salmonella and E.Coli – bacterial, acquired by
eating contaminated food. Store and cook
foods properly.
Giardia –a microorganism that infects the
digestive system. “Recreational water illness”






HIV / AIDS –
Lyme Disease – spread by tick bites.
West Nile Virus – spread by infected
mosquitoes. bird- mosquito-human
SARS – viral illness first reported in Asia.
Mad Cow Disease- “bovine spongiform encephalopathy”
Epidemic- a disease outbreak that affects many
people in the same place and at the same time.
How diseases affect the world



Pandemic – a global outbreak of an infectious
disease.
Travel- tourism and trade
Mutation of Pathogens-