Chapter Seventeen Immunity and Infection

Major Pathogens Major Pathogens VirusesViruses BacteriaBacteria FungiFungi Protozoan Parasitic worms Prions Disease producing agent which could produce toxins

Chain of Infection

Identify Body Defenses

Identify Immune Response Against Pathogens

Inflammatory Response When the body has been infected, one of the responses is the Inflammatory ResponseWhen the body has been infected, one of the responses is the Inflammatory Response Special cells release histamine which causes heat, swelling, and redness of that areaSpecial cells release histamine which causes heat, swelling, and redness of that area White blood cells attack the invader, attempting to destroy themWhite blood cells attack the invader, attempting to destroy them

The Immune Response The Immune Response consists of two functionsThe Immune Response consists of two functions Natural (innate)Natural (innate) Acquired (adaptive)Acquired (adaptive) The Immune Response consists of 4 phasesThe Immune Response consists of 4 phases Recognition of the invaderRecognition of the invader Amplification of defensesAmplification of defenses AttackAttack SlowdownSlowdown

How Does One Achieve Immunity? After an infection, lymphocytes created during the amplification phase of the immune response serve as memory T and B cellsAfter an infection, lymphocytes created during the amplification phase of the immune response serve as memory T and B cells They continue to circulate in the blood and lymphatic system for years or even longerThey continue to circulate in the blood and lymphatic system for years or even longer If the same antigen enters the body, the T and B recognize this and destroy itIf the same antigen enters the body, the T and B recognize this and destroy it The ability to have lymphocytes remember previous infections is known as acquired immunityThe ability to have lymphocytes remember previous infections is known as acquired immunity

5 Stages of an Infection 1.Incubation stage 2.Prodromal stage 3.Clinical stage 4.Decline stage 5.Recovery stage

Immunizations Vaccinations are when the immune system is given an antigen which is not considered dangerousVaccinations are when the immune system is given an antigen which is not considered dangerous The body produces antibodies, which prevent serious infection against that particular diseaseThe body produces antibodies, which prevent serious infection against that particular disease Vaccines are made by either weakened pathogens or killed pathogens, which still illicit the production of antibodies (active immunity), or antibodies can be injected (passive immunity) to create temporary immunityVaccines are made by either weakened pathogens or killed pathogens, which still illicit the production of antibodies (active immunity), or antibodies can be injected (passive immunity) to create temporary immunity

Allergies: The Body’s Defense Gone Haywire 50 million Americans are affected by allergies50 million Americans are affected by allergies This is a result from a hypersensitive and overactive immune systemThis is a result from a hypersensitive and overactive immune system The immune system mounts an attack on a harmless substanceThe immune system mounts an attack on a harmless substance The results create the unpleasant and potentially serious symptoms of an allergyThe results create the unpleasant and potentially serious symptoms of an allergy

Allergens PollenPollen Animal danderAnimal dander Dust mites and cockroachesDust mites and cockroaches MedicationMedication Types of metalsTypes of metals Mold and mildew Foods Insect stings Plants Substances found in cosmetic products

The Allergic Response Most allergic reactions are due to the production of immunoglobulin E (IgE)Most allergic reactions are due to the production of immunoglobulin E (IgE) Mast cells release large amounts of histamines and other compounds into the surrounding tissueMast cells release large amounts of histamines and other compounds into the surrounding tissue Histamine has many effects, such as congestion, redness, swelling, etc. but the most serious kind of allergic reaction is anaphylaxisHistamine has many effects, such as congestion, redness, swelling, etc. but the most serious kind of allergic reaction is anaphylaxis

Bacterial Infections MeningitisMeningitis TuberculosisTuberculosis PneumoniaPneumonia Strep Throat and other streptococcal infectionsStrep Throat and other streptococcal infections Urinary Tract InfectionsUrinary Tract Infections Toxic Shock Syndrome and other staphylococcus infections Lyme disease and other Tickborne infections Ulcers Tetanus Pertussis Antibiotics interrupt the new production of bacteria by damaging them

Viral Infections Common ColdCommon Cold MeaslesMeasles MumpsMumps InfluenzaInfluenza Measles, Mumps, RubellaMeasles, Mumps, Rubella Chicken Pox, Cold sores, and herpesvirus infections Viral Encephalitis Viral Hepatitis Poliomyelitis Rabies Warts Treatment is the use of anti-viral medications

Fungal Infections A fungus is a primitive plantA fungus is a primitive plant 50 of thousands of fungi cause disease among humans50 of thousands of fungi cause disease among humans Candida albicans is a common fungus found naturally in the vagina of most women, which causes infectionsCandida albicans is a common fungus found naturally in the vagina of most women, which causes infections Other common forms are athlete’s foot, jock itch, and ringwormOther common forms are athlete’s foot, jock itch, and ringworm Fungal infections can be deadly in people with impaired immune systemsFungal infections can be deadly in people with impaired immune systems

Protozoan Infections Single-celled organisms, which alternate between activity and inactivitySingle-celled organisms, which alternate between activity and inactivity Common infections include:Common infections include: MalariaMalaria GiardiasisGiardiasis TrichomoniasisTrichomoniasis TrypanosomiasisTrypanosomiasis Amoebic dysenteryAmoebic dysentery

Parasitic Worms Considered the largest organism that can enter the body to cause infectionConsidered the largest organism that can enter the body to cause infection Worms, including the tapeworm and hookworm, can grow to a length of many feet, especially in the intestinal tractWorms, including the tapeworm and hookworm, can grow to a length of many feet, especially in the intestinal tract Worm infections can originate from contaminated food or drinkWorm infections can originate from contaminated food or drink

Prions Known as ‘proteinaiceous infectious particles’Known as ‘proteinaiceous infectious particles’ Prions lack DNA or RNA and consist of only proteinPrions lack DNA or RNA and consist of only protein They spread by triggering normal proteins to change their structure to the abnormal, damaging formThey spread by triggering normal proteins to change their structure to the abnormal, damaging form Examples are:Examples are: Creutzfeldt-Jakob a.k.a. ‘Mad Cow’Creutzfeldt-Jakob a.k.a. ‘Mad Cow’ ScrapieScrapie

Selected Infections of Concern SARSSARS E. coliE. coli HantavirusHantavirus Monkey Pox Ebola Avian flu

Factors Contributing to Emerging Infections Drug ResistanceDrug Resistance PovertyPoverty Breakdown of Public Health MeasuresBreakdown of Public Health Measures Environmental ChangesEnvironmental Changes Travel and Commerce Mass Food Production an Distribution Human Behavior

Chapter Seventeen Immunity and Infection