Chapter 24 Warm Up What are the three methods of transmission of communicable diseases? Look in your book!

Causes of Communicable Diseases  The common cold and influenza (Flu) is caused by viruses, or genetic material, which take control of the body’s cells to produce more viruses.  Bacteria produce a toxin that kills cells or interferes with their functions.  Fungi, such as molds and yeasts, can cause skin or lung disease.  Protozoans and Rickettsias also can cause disease.

How Communicable Diseases are Transmitted  Direct contact – touching, biting, kissing, sneezing, coughing.  Indirect contact – touching an area where someone with a cold has sneezed.  Also transmitted through the air.

Strategies for Preventing C. Diseases  Wash your hands.  Handle Food Properly.  Eat a balanced diet.  Avoid sharing eating utensils.  Prepare and store food properly.  Avoid unnecessary contact with ill people.  Take care of yourself when you’re ill.  Get vaccinated.  Practice abstinence from sexual activity.  Learn to manage stress.

Chapter 24 Lesson 2  Physical and Chemical Barriers –These barriers are your body’s first line of defense. –The skin and mucous membranes block pathogens from invading the body. –Enzymes destroy pathogens.

Care of the Immune System  Follow a sensible eating plan.  Get plenty of rest.  Get about an hour of daily physical exercise.  Avoid sharing personal items.  Avoid tobacco, alcohol, and other drugs.  Avoid sexual contact.  Keep your immunizations up to date.

Chapter 24 Lesson 3  Respiratory Infections –The common cold is a viral infection that causes inflammation of the mucous membranes, which line the nose and throat.  There is no cure.  Using analgesics can help treat the symptoms. –Influenza is a viral infection of the respiratory tract.  It can lead to pneumonia  Antiviral drugs are available.

continued  Respiratory Infections (cont.) –Pneumonia – short lived, but it weakens the body and can cause death. –Strep throat – bacterial infection spread by direct contact, and can be treated with antibiotics. –Tuberculosis – Spread through the air; bacterial disease that often attacks the lungs.

Hepatitis  Hepatitis A – most commonly spread through contact with feces of an infected person.  Hepatitis B – transmitted through sexual contact with an infected person.  Hepatitis C – most common chronic blood-borne infection in the U.S.

Emerging Infections  These infections can be transported across the borders.  Population movement is a factor in the increase of Lyme Disease.  The widespread use of antibiotics has resulted in pathogens that have become resistant.  Changes in food technology increase the chance that contaminated food will infect people.  With the ease of travel, contagious agents of bioterrorism are spread rapidly.