Introduction to Oral Microbiology

Question 1

HIV transmission?

Answer 1

Body fluids, except saliva which is not infectious

Question 2

What does HIV infect

Answer 2

CD4 T cells

Question 3

Describe the HIV

Answer 3

• Large ssRNA, enveloped virus
• Reverse transcriptase puts viral RNA into host DNA
• Virions are produced and excreted from infected cell

Question 4

Oral symptoms and signs of HIV:

Answer 4

• Acute infection with flu-like symptoms
• Low CD4 cell count
• High plasma HIV RNA levels
• Xerostomia (Dry mouth)
• Candidiasis (Oral thrush)
• Oral hairy leukoplakia (white plaque lesion)
• Kaposi’s sarcoma (Purple lesions)
• Periodontal disease

Question 5

Transmission of Hepatitis B?

Answer 5

Body fluid, except saliva which is not infectious

Question 6

Hepatitis B function?

Answer 6

• Inflammation of the liver?

- Infects liver cells: dsDNA virus enters, dsDNA does not integrate into host DNA

Question 7

Properties of hepatitis B

Answer 7

• Very high replication rate
• Very low infectious dose
• 50% of affected are undiagnosed

Question 8

Hepatitis B vaccine?

Answer 8

Only works if body produces anti-HBV antibodies, and needs booster over time

Question 9

Describe Hepatitis C

Answer 9

• Inflammation of the liver
• Transmission = blood
• HCV infects liver cells: ssRNA virus infects cells
• 1000x lower plasma number than HBV
• 70% cases develop liver disease

Question 10

Risk from needlestick injury (if patient is positive):

Answer 10

• HBV = 23-62%
• HCV = 1.8%
• HIV = 0.3%