Infectious Disease

A disease caused by a Pathogen that can be passed from person to person Infectious Disease 1An organism that causes diseaseMost are microscopic Pathogen 2Louis PasteurProved the Theory of Spontaneous Generation was false Showed that airborne microbes were the cause of disease Discovered microbes could be killed by the heating of the liquid they were in3Robert KochExperimented with various dyesthat stain bacteria and make them more visible under the microscopeAlso devised an ingenious method of separating a mixture of bacteria Demonstrated that each infectious disease is caused by a specific pathogen inoculated an animal with the bacteria and passed the resulting infection from one animal to another until, at the end of the experimental chain, only one type of bacterium remained

4Four Types of Pathogens Protists Single celled organismsAmoeba, Giardia, Plasmodium vivaxDysentery, Giardia, Malaria FungiDermatophytesAthletes Foot, Ringworm 5Viruses Nucleic acid with a protein coverDNA or RNADamage or destroy cells by reproducing inside the cellAdenovirus, Influenza virus, HIV Cold, Flu, AIDS 6BacteriaCan damage cells directlyStreptococcus, Strep throatCan damage cells indirectly by producing toxinsClostridium tetani,Tetanus Can use shapes and arrangement of bacteria to help identify

7Sources of Pathogens Soil, food, water, airContaminated objectsInfected animalsAn infected person Disease can be spread through contact with any of the above Sources of Pathogens. 8How Pathogens are Spread Contact with Infected peopleInfected animalsContaminated animalsContaminated food, water or soil9Predicting Casualties Chart the growth of bacterium that reproduces by simple cell division once every 20 minutes. Make a table and graph showing the number of organisms created during a 3-hour period. 10 20 min Time Periods Number of Cells01122438416532664712882569512Predicting Casualties 11Exponential Growth1220 minute Time Periods Number of Cells01.012.024.038.0416.0532.0664.07128.08256.09512.0101,024.0112,048.0124,096.0138,192.01416,384.01532,768.01665,536.017131,072.018262,144.019524,288.0201,048,576.0212,097,152.0224,194,304.0238,388,608.02416,777,216.02533,554,432.02667,108,864.027134,217,728.028268,435,456.029536,870,912.0301,073,741,824.0Predicting Casualties How long till we reach a million cells? 1314MonthsNo Action Educ. Campaign Preventative Meds. 110,000.0 10,000.0 10,000.0211,200.010,200.010,800.0312,544.010,424.011,664.0414,049.310,674.912,597.1515,735.210,955.913,604.9617,623.411,270.614,693.3719,738.211,623.015,868.7822,106.812,017.817,138.2924,759.612,459.918,509.31027,730.812,955.119,990.01131,058.513,509.721,589.21234,785.514,130.923,316.41338,959.814,826.625,181.71443,634.915,605.827,196.21548,871.116,478.529,371.91654,735.717,455.931,721.71761,303.918,550.734,259.41868,660.419,776.737,000.21976,899.721,149.939,960.22086,127.622,687.943,157.02196,462.924,410.546,609.622108,038.526,339.750,338.323121,003.128,500.554,365.424135,523.530,920.658,714.61516MonthsPreventative Meds and Educ. Campaign11000029800.039584.049350.759098.868826.778532.888215.497872.7107502.5117102.7126670.9136204.6145700.9155157.0164569.6173935.1183250.0192510.0201710.721847.622-84.623-1091.424-2178.7Predicting Casualties 1718An Ounce of Cure Set up Petri dishes with pathogensChoose 3 medications to test for growth inhibitionBe sure to label carefully and draw accurately193 Lines of Defense Fighting Disease 20First line of defenseSurfaces of skin, breathing passages, mouth, stomachTrap and kill most of the pathogens that come into contact with them 21How it WorksSkin Destructive chemicalsOil SweatDead cells fall offTightly packed cells dont allow access

22How it WorksBreathing Passages Mucus and cilia trap and remove pathogensSneeze or cough to force pathogens out

23How it Works Mouth and Stomach Destructive chemicals SalivaStomach acid 24Second line of defenseInflammatory ResponseFluid and white blood cells leak from blood vessels into nearby tissuesWBCs help fight pathogens Phagocytes 25Inflammatory ResponseBlood vessels widen and increase blood flow to the area causing rednessLeaked fluid causes swelling Some pathogens do not grow and reproduce at higher temperatures 26Third line of defenseImmune System T cells (Helper and Killer) B cells Antibodies Lymphocytes distinguish between different kinds of pathogens 27Third line of defenseAntigensMolecules that the immune system recognizes either as part of the body or as coming from outsideLike a team uniform28Third line of defenseAIDSA virus that attacks the Immune SystemEnters Helper T cellsOver time, HIV does damage the immune system, and the body will lose its ability to fight disease.29Two types of Immunity Active Results from getting disease or From vaccinationLong lasting PassiveAntibodies given to fight diseaseShort term (months) Both protect the body from pathogens

30Active Immunity When a person acquires immunity because their own immune system has produced antibodies in response to the presence of a pathogen Produced by cells of the immune system as part of the immune response

31Active Immunity Memory cells When a pathogen enters the body memory cells recognize the antigen and start the immune response so quickly that the persons wont get sick

32Active Immunity VaccinationVaccinePathogens (viruses) that have been weakened or killed but can still trigger an immune responseAntibiotic Bacteria only33Active Immunity 3 things you can do to help your Body recover when you are sickGet plenty of rest Drink lots of fluidsEat well balanced meals

34Passive Immunity Does not last a lifetime (short term) Antibodies that are passed to the blood of baby from the mothers blood during pregnancy

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