Place Invaders

1. Place Invaders Invasive Diseases

2. Infectious Disease • Also known as • Contagious Disease • Communicable Disease • Transmissible Disease • Caused by a pathogen that causes disease • Not all infections cause disease that can be transmitted

3. Infectious Diseases • Pathogens can be: • Viruses • Bacteria • Parasites • Fungi • Protozoa • Prions

4. Viruses Can Infect • Plants • People • Animals • Bacteria • Other Single Celled-organisms

5. Viruses in Plants • Transmitted by -Chewing Animals such as Insects • -Sucking Insects such as Aphids • -Fungi • -Single-celled Organisms • -People Through Tools or Hands • -Generation to Generation Through Seeds and Pollen • -Nematodes

6. Viruses in Plants • Don’t infect humans or animals • Reduce Yield • Deform fruits and vegetables Plum Pox Virus in peaches Tomato Mosaic Virus in cucumbers

7. Examples of Plant Viruses Pepper mild mottled virus Tobacco Mosaic virus Tobacco Mosaic Virus in Orchids

8. Examples of Plant Viruses Potatoes infected with Y virus Tobacco Mosaic virus in tomatoes Healthy Eggplant (left) compared to damaged eggplant infected with Tomato Bushy Stunt virus

9. Would you eat these?

10. Virus Control In Plants • Once plants are infected with viruses little can be done. • There is not effective treatment. • The best control is prevention. • Scientists are working on creating vaccines but they are in the early stages of research.

11. Virus Prevention Includes • insect control • removing weeds that may harbor viruses or their insect vectors • grow from seeds • for plants that transmit viruses through seed, use indexed seed • discard all virus infected plants • disinfect tools used for vegetative propagation

12. Viruses In Animals • Transmitted • Biting and/or Blood-sucking Insects • Coughing • Sneezing • Fecal-oral Route • Direct Blood to Blood • Direct Body Fluids • Sexual transmission

13. Viruses In Animals • Some Viruses can infect a number of species • Other Viruses are Species Specific • Viruses can mutate • new “strain” of a virus • expand host populations • alter transmission method • Viruses need live tissue

14. Viruses In Animals • Vaccines are used to create immunity to viruses • Antivirals can now be used to treat some viruses • Tamiflu • Relenza • Antibiotics DO NOT work on viruses!

15. Examples of Animal Viruses • Foot and Mouth Disease • Hemorrhagic Fever • Influenza (flu) • Avian Influenza • Herpes Viruses • West Nile Virus • Encephalitis • Yellow Fever Influenza Virus

16. Examples of Animal Viruses • Distemper • Rabies • Measles • Polio • Chickenpox • Smallpox Girl with Smallpox in Bangladesh in 1973

18. Bacteria • Single-celled microorganisms • Rods, spheres, spirals • Reproduce by Binary fissionhttp://en.wikipedia.org/wiki/File:Binary_fission_anim.gif

19. Bacteria • Live in every environment on earth • Soil • Fresh water • Salt water • Acidic hot springs • On all surfaces • In very inhospitable places • Live in and on the human body • Live in and on plants and animals

20. Bacteria • Very important in nutrient cycles • Nitrogen fixation • Decomposition • Some bacteria beneficial • Probiotics • Fermented foods • Cheese • Yogurt • Pickles • Sourdough bread

21. Bacteria • Some bacteria live symbiotically • Some bacteria harmful • pathogens • Most bacteria do not affect humans, plants or other animals • Most bacteria have not been classified or studied

22. Bacterial Diseases • Cholera • Tuberculosis • Anthrax • Leprosy • Syphilis • Bubonic plague • Bacterial pneumonia • Tetanus Bacillus anthracis (Anthrax)

23. Eschericia Coli (E. Coli) http://en.wikipedia.org/wiki/File:E.-coli-growth.gif

24. Bacteria • Exist virtually everywhere including in the air • So transmission is possible by every means • Bacterial can live for years in very inhospitable environments • Spores in soil

25. Post-harvest Bacteria • Bacteria do not only cause disease in plants and animals • Bacteria cause food spoilage • Bacteria cause food-borne illnesses • Food preservation and pasteurization techniques are used to prevent both

26. Parasites • Live in or on a host and cause harm • Nourishment • Protection • May be as small as a single cell • Protozoa • 1 to 2 micometers • May be a large worm • Helminths • Just visible to naked eye to 2 meters long

27. Parasites • May have a single permanent host • Or many intermediary hosts • In animals, often excreted in feces • Infest animals and plants • Humans • Mammals • Birds • Insects

28. Parasites May Be • Transmitted from human to human • Transmitted from animal to animal • Transmitted from human to animal • Transmitted from animal to human • Transmitted from human to bird to mammal and back to human • May be transmitted by insect vectors

29. Parasites • Transmitted from fecal contamination • Transmitted from direct blood contamination • Transmitted by vectors

30. Diseases Caused by Parasites • Found in food or water • Cause foodborne illness • Cause waterborne illness • Can range from mild discomfort to debilitating illness or even death • Transmitted primarily through fecal contamination

31. Diseases Caused by Parasites • Trichomoniasis • Malaria • Giardia • Cryptosporidium • Cyclospora • Toxoplasmosis • Trichinosis • Tapeworms

32. Prevention of Parasitic Diseases • Proper hand washing with soap • Drink either municipal treated water or boil water • Cook foods thoroughly • Do not swallow or breath in water when swimming • Consume only pasteurized beverages • Use gloves when handling uncooked meat, cat litter, gardening.

33. Human Fungal Diseases • Athlete’s Foot/Jock Itch • Yeast Infections (Candida) • Thrush • Ringworm • Diaper Rash • Fungal Sinusitis • Nail Fungus • Histoplasmosis

34. Plant Fungal Diseases • Powdery Mildew • Fusarium Wilt • Root rots • Phytopthora infestans – late blight • Cause of the Irish Potato Famine • Still the most pathogen of potato crops Powdery Mildew

35. Diseases Caused by Fungi • Transmitted by contact with fungal spores • Transmitted by air • Treated with antifungal agents in humans and animals • Treated with fungicides in plants

36. Protozoan Diseases • Malaria, Giardia, Cryptosporidium, and Toxoplasmosis • African Sleeping Sickness • Amebic Dysentery

37. Protozoan Diseases • Transmitted by insect vectors • TseTse Fly • Malarial mosquito • Transmitted in contaminated water • Transmitted in contaminated food • Contamination with cysts from infested fecal material

38. Prevention of Protozoan Diseases • Proper hand washing with soap • Boil water before drinking • Cook foods thoroughly • Prevent fly contamination of food • Drink only pasteurized beverages • Strict sanitation when working with lab animals

39. Treatment of Protozoan Diseases • Drug treatments are available • Depending upon infestation, a sequential use of several drugs may be used. • Chlorine does not kill protozoans so heating water to 122°F is necessary

40. Diseases Caused by Prions • Prions are a caused by a yet to be determined transmission agent • cause abnormal folding of proteins in the brain which leads to brain damage

41. Diseases Caused by Prions • Mad Cow Disease – BSE • Scrapie • Chronic Wasting Disease • Creutzfeld-Jakob Disease • Kuru

42. Treatment of Prion Diseases • The disease is always fatal. No known treatment is available. • Brain and spinal tissue is removed from slaughtered animals prior to butchering to prevent any possible contamination by prions.