1. 1 Review Describe how bacteria cause disease Review How do viruses cause disease Relate Cause and Effect Are vaccines effective before or after infection- explain 2 Review Why are emerging disease of particular concern Propose a Solution What actions could your school take to help combat the evolution of “superbugs” and explain how these actions could make an impact

2. Ch 20 Viruses and Prokaryotes
20.3 Diseases Caused by Bacteria and Viruses

3. Bacterial Diseases Bacteria produce disease in one of two general ways
Destroy living cells and tissues of the infected organism
Release toxins (poisons) that interfere with the normal activity of the host cell.

4. All known prokaryotic pathogens are bacteria
Microorganisms that cause disease
All known prokaryotic pathogens are bacteria
No archaea are known to be pathogens.

5. Damaging Host Tissue Tuberculosis Inhaled into the lungs
Its growth triggers an immune response that can destroy large areas of tissue.

6. Releasing Toxins
Botulism
Deadly form of food poisoning.

7. Controlling Bacteria Physical Removal Disinfectants Food Storage
Food Processing
Sterilization by Heat.

8. Physical Removal
Washing hands or other surfaces with soap under running water doesn’t kill pathogens
It dislodges both bacteria and viruses.

9. Disinfectants Chemical solutions that kill bacteria
Can be used to clean bathrooms, kitchens, hospital rooms, and other places where bacteria may flourish.

10. Food Storage
Low temperatures slow the growth of bacteria and keep most foods fresher for a longer period of time than possible at room temperature.

11. Food Processing
Boiling, frying, or steaming can sterilize many kinds of food by raising the temperature of the food to a point where bacteria are killed.

12. Sterilization by Heat
Sterilization of objects such as medical instruments at temperatures well above 100° Celsius can prevent the growth of potentially dangerous bacteria.

13. Preventing Bacterial Diseases
Vaccine
Preparation of weakened or killed pathogens or inactivated toxins
Prompts the body to produce immunity to a specific disease
Immunity
Body’s ability to destroy pathogens or inactivated toxins.

14. Treating Bacterial Diseases
Antibiotics
Drugs used to attack a bacterial infection
Block the growth and reproduction of bacteria
Disrupt proteins or cell processes that are specific to bacterial cells
Do nothing against viruses.

15. Viral Diseases
Attack and destroy certain cells in the body, causing the symptoms of the associated disease
Cause infected cells to change their patterns of growth and development.

16. Preventing Viral Diseases
Vaccines.

17. Innovations in Vaccines
1769 Edward Jenner performs the first inoculation against smallpox, using the less harmful but similar cowpox virus.

18. Innovations in Vaccines
1880s Louis Pasteur develops vaccines against anthrax and rabies.

19. Innovations in Vaccines
1923 Albert Calmette and Camille Guerin develop a vaccine against tuberculosis.

20. Innovations in Vaccines
1950s Jonas Salk develops a polio vaccine that uses killed viruses. Albert Sabin develops a polio vaccine that uses weakened viruses.

21. Innovations in Vaccines
1981 A vaccine against hepatitis B that uses recombinant DNA gains government approval.

22. Innovations in Vaccines
2006 A vaccine against human papillomavirus, a virus known to cause certain cancers, gains approval.

23. Preventing Viral Diseases
Washing your hands frequently
Avoiding contact with sick individuals
Coughing or sneezing into a tissue or your sleeve, not into your hands.

24. Treating Viral Diseases
Cannot be treated with antibiotics
Antiviral drugs attack specific viral enzymes.

25. Emerging Diseases
An unknown disease that appears in a population for the first time or a well-known disease that suddenly becomes harder to control.

27. More of a Threat Changes in lifestyle and commerce High-speed travel
Huge quantities of food and consumer goods are now shipped between regions of the world that previously had little contact with each other
Human populations that were once isolated are now in close contact with more developed parts of the world.

28. Emerging diseases are of particular concern because of their sudden appearance and resistance to existing control methods.

29. “Superbugs”
Bacteria resistant to whole groups of antibiotics and that transfer drug-resistant genes through conjugation
Result of natural selection.

30. Methicillin-resistant Staphylococcus aureus
MRSA
Skin infections
Especially dangerous in hospitals
Infection can be fatal for people in hospitals and nursing homes.

32. New Viruses
Can jump species due to fast replication and high rate of genetic mutations
Evidence that this is how HIV moved from nonhuman primates into humans.

33. Gene shuffling among different flu viruses led to “bird flu”
Very similar to 1918 flu
Very slight genetic changes to jump to humans.

34. Prions Misfolded proteins
Cause a chain reaction of misfolding in other normal proteins they contact.