Week 3 Virology

Question 1

How is Hep A transmitted and what are the consequences?

Answer 1

Transmitted:
- Fecal-oral/food/water-borne
- Sexually transmitted

Sequelae:
- Usually self-limiting
- May relapse
- Fulminant hepatitis

Question 2

How is Hep B transmitted and what are the consequences?

Answer 2

Transmitted:
- Person-person
- Blood or body fluids./drug abuse
- Sexually transmitted

Sequelae:
- Chronic infection
- Hepatocellular carcinoma
- If infected at a young age, infx usually lifelong
- If infected later on, can be treated

Question 3

How is Hep C transmitted and what are the consequences?

Answer 3

Similar to Hep B, but higher risk with HIV infection

Sequelae:
- Chronic infection
- Liver cirrhosis, requiring liver transplant
- Hepatocellular carcinoma
- Can be treated if early

Question 4

How is Hep E transmitted and what are the consequences?

Answer 4

Transmission:
- Fecal-oral route

Sequelae:
- Self-limited disease

Question 5

What are the clinical presentations of dengue?

Answer 5

• Mostly asymptomatic
• Fever with mild symptoms
• Symptomatic dengue

Question 6

What are the clinical phases of dengue?

Answer 6

• Febrile phase
• Critical phase
• Recovery phase

Question 7

What happens during the febrile phase in dengue infection?

Answer 7

• Sudden high fever lasting 2-7 days
• Face flushing, erythema, myalgia, N&V, mucosal membrane bleeding
• Drop in WBC

Question 8

What happens during the critical phase in dengue infection?

Answer 8

• ^ HCT levels
• Decrease in PLT
• Usually 24-48 hours
• Pleural effusion or ascites if severe enough to worsen

Question 9

What is the criteria for diagnosing dengue w/o warning signs? (IMPT)

Answer 9

• Fever
  + 2 of the following:
• N&V
• Rash
• Aches
• Leukopenia
• Tourniquet test positive

Question 10

What is the criteria for diagnosing dengue w/ warning signs? (IMPT)

Answer 10

• Abdominal pain or tenderness
• Persistent vomiting
• Fluid accumulation
• Mucosal bleed
• Liver enlargment >2 cm
• ^HCT

Question 11

What is the criteria for diagnosing severe dengue? (IMPT)

Answer 11

• Severe plasma leakage leading to shock/DSS
• Severe bleeding
• Impaired consciousness
• Other organ involvement

Question 12

How to measure pulse pressure and what range indicates shock?

Answer 12

• SBP minus DBP = PP
• <20mmHg is shock

Question 13

What lab tests are required to assess and diagnose dengue? (IMPT)

Answer 13

• WCC
• PLT
• Baseline HCT
• PCR for dengue virus
• Serum for POCT