HOW BACTERIA CAUSE DISEASEHTTPS://WWW.YOUTUBE.COM/WATCH?V=FNAAISFIPDU

WATCH THE ABOVE VIDEO (1:27:30). START AROUND 4:20:00.

This PowerPoint presentation is meant to be printed and used as a guide while watching the How Bacteria Cause Disease video that can be opened from the above link. Occasionally there will be something in this Ppt that is not in the video, so don’t be concerned if you see something in the Ppt that is not in the video.

Questions that students should answer from the videos are on the slides. Students should print these slides.

Slides 17-21 contain links to additional videos about specific diseases and the questions you should answer for each.

OUTLINE: HOW BACTERIA CAUSE DISEASE VIDEO

1. Types of disease causing organisms2. Concepts of infectious disease3. Beneficial and detrimental effects of

inflammation and what causes those effects4. Bacterial structure and its relationship to

pathogenesis5. Fundamentals of pathogenesis6. Structure and action of endotoxins7. Examples of exotoxins8. How one bacterium can cause many different

diseases

IMPORTANT ORGANISMS THAT CAUSE DISEASE

SEE NEXT SLIDE FOR QUESTIONS ABOUT EACH MAJOR GROUP

• Worms (Helminths): Roundworms, flatworms

• Protozoans: Found in the Kingdom Protistia;, Malaria (Plasmodium)

• Fungi: Yeasts and molds; Candida, Cryptococcus

• Bacteria: Streptococcus, E. coli

• Viruses: herpes, human • papilloma virus, influenza, Ebola

Which of these was your instructor infected with?

Giardia,

• Answer the following for worms, protozoans, fungi, bacteria and viruses:o Multicellular, unicellular, or noncellular?o Eukaryotic, prokaryotic, or neither?o What molecule is used as the genetic (hereditary)

material?

• Why are viruses obligate intracellular parasites?

• Can viruses acquire their own energy and make their own proteins?

WHY DO PEOPLE GET INFECTIOUS DISEASES?

Host Factors• What are some differences between our

(the host) immune system’s innate host factors and adaptive host factors affecting our ability to fight off disease?

Microbe Factors• What does ‘dose’ mean in this context?• What does ‘virulence’ mean? • Later in the video the speaker discusses

some virulence factors. By the time the video is over, you should be able to give a description of each: capsules (glycocalyx), pili, exotoxin, endotoxin, and plasmids.

See text Chap. 3 pp. 68 (Appendages), -70, 76

PATTERNS OF INFECTIOUS DISEASE

Define the following:

1. Incubation Period2. Prodromal Period3. Period of Specific Illness (called the Period of

Invasion in the text)4. Convalescence5. Recovery

DOES MY PATIENT HAVE AN INFECTIOUS

DISEASE?

What are common signs and symptoms of an infectious disease?

Can these signs/symptoms be caused by other types of diseases?

ROLE OF INFLAMMATION

Can inflammation be beneficial and detrimental?

What are some signs and symptoms of inflammation?

Why is an increased blood flow beneficial?

What causes swelling during inflammation?

What is pus made of?

What are neutrophils?

Text Fig. 3.1 p.63Many important bacterial structures contributing to disease or the diagnosis of disease are discussed in the video.

See the Notes pane of the slide for additional notes.

The next slide contains questions and more notes from the video.

SOME BACTERIAL CELL STRUCTURES IMPORTANT TO DISEASE

• Capsules: What do bacterial capsules prevent?• Cell wall: Antibiotics often target the bacterial

cell wall since it is vital to the life of the bacterial cell.

• Plasmids: Small extrachromosomal (outside of the large bacterial chromosome) DNA molecules. Plasmids may contain genes providing a higher virulence to the bacterium (for example toxins) or antibiotic resistance.

• Ribosomes: Perform protein synthesis; also the target site of some antibiotics

• Pili: Fimbriae (attachment pili) and Conjugation pili (used for DNA transfer)

• The outer membrane present in Gram negative bacteria contain endotoxins.

FUNDAMENTALS OF PATHOGENICITY

MODES OF TRANSMISSION

• What are some forms of transmission to the host?

• Why is it important to know the transmission route?

• What are some ways we can break the chain of transmission?

• What is a reservoir?

• Can the normal flora (resident microbiota) cause disease? If so, when?

• What does the text call ‘colonization resistance’ (p. 291 text)

• What are some ways bacteria are able to attach to our tissues?

• How does a bacterial slime layer (glycocalyx) help some bacteria colonize our tissues?

• How does a bacterial capsule help a bacterium to colonize our tissues?

• What is a biofilm?

FUNDAMENTALS OF PATHOGENICITY

COLONIZATION AND GROWTH

FUNDAMENTALS OF PATHOGENICITY

INVADING & HARMING OUR TISSUES

Inflammation:• Do some bacteria cause disease mostly by

the inflammation they induce?

• What type of phagocytic white blood cell secretes molecules called cytokines (ex: interleukins) that promote inflammation?

• How does inflammation contribute to pneumonia?

Endotoxins (lipopolysaccharides or LPS):

• What type of bacteria have endotoxins- Gram positive or Gram negative?

• What are the 2 main mechanisms of action by which endotoxins cause disease signs and symptoms?

FUNDAMENTALS OF PATHOGENICITY

INVADING & HARMING OUR TISSUES

Exotoxins: Exotoxins may cause disease even if the bacteria are not present… if the bacteria were present previously, made the toxin, and secreted it out of the cell into the surrounding environment. The toxin may then attach to host cell receptors and enter the cell. However, some bacteria attach to the host and inject the toxin into the host’s cell.

What are the effects of the Botulism toxin, the Tetanus toxin, and the Cholera toxin?

FUNDAMENTALS OF PATHOGENICITY

INVADING & HARMING OUR TISSUES

WHY SOME BACTERIA CAN CAUSE MORE THAN ONE DISEASE

By various processes, bacteria can acquire new DNA (new genes) from other bacteria. Much of the new DNA comes in plasmids. The bacteria can then exhibit new traits which increase their virulence and ability to colonize different tissues.

Examples of the traits new genes may provide: new toxins, new ways to attach to different parts of the body, and resistance to antibiotics.

E. coli

WORMSAfter watching the How Bacteria Cause Disease video, watch the videos in slides 17-21, and answer the questions. Two links are to CDC sites (Centers for Disease Control)

Monsters Inside Me Ep 6: Deadly Roundworms (3:15)• What white blood cell becomes elevated when

you are infected with a parasite (primarily meaning a helminth)?

• What are some symptoms of Toxocara canis infection?

PROTOZOANSBrain –eating Amoeba

https://www.youtube.com/watch?v=1QdVVC3MjCc (2:22)https://www.youtube.com/watch?v=Ue2eE9SYCyk (2:13)

• Where does the amoeba Naegleria fowleri live?• How does it enter the body?• How does it protect itself from your immune

system?• What organ is affected?• How can people protect themselves?

FUNGIhttps://www.youtube.com/watch?v=U5uuOzi7D8Q (1:53)

https://www.youtube.com/watch?v=P0fdhPeTKLQ (6:03)

• What is the name for an infection of the lungs? 

• How do you acquire blastomycosis?

• Can this fungus affect other organs?

BACTERIALyme Disease - Caused by the spirochete Borrelia burgdorferi

An internet search would reveal the controversy surrounding the transmission, occurrence, diagnosis, and treatment concerning Lyme disease. All medical professionals should remember that as new data is acquired, our understanding may change. https://www.youtube.com/watch?v=6u8bdWUwB3o (2:36)

http://www.cdc.gov/lyme/

• Can Lyme disease co-present with other infections?• How is Lyme Disease transmitted?• How do the signs and symptoms of Lyme disease develop over

time?• What are some preventative measures?

VIRUSESWEST NILE VIRUS

http://www.animalplanet.com/tv-shows/other/videos/killer-outbreaks-west-nile-virus.htm(2:38)

http://www.cdc.gov/westnile/index.html

• What other animal is affected by West Nile Virus?

• How is it transmitted?

• Where is West Nile virus located in the USA?

• How can it be prevented?

• What are the signs and symptoms of West Nile Virus and how may it develop over time?