MCQs on Viral hemorrhagic fevers (VHFs)

                           MCQs on Viral hemorrhagic fever

1. Which of the following regions is known to have a high prevalence of Lassa fever?
a) Europe
b) North America
c) Southeast Asia
d) West Africa

2. Yellow fever is primarily transmitted by:

a) Fleas
b) Flies
c) Mosquitoes
d) Ticks

3. Severe dengue, which can lead to hemorrhagic symptoms, is also known as:
a) Dengue Fever
b) Dengue Hemorrhagic Fever
c) Dengue Malaria
d) Dengue Shock Syndrome

4. How is the Marburg virus primarily transmitted to humans?
a) By contact with infected rodents
b) By airborne transmission
c) Through the consumption of contaminated water
d) Through the bite of infected ticks

5. Crimean-Congo Hemorrhagic Fever (CCHF) is mainly transmitted to humans through:
a) Consumption of undercooked pork
b) Mosquito bites
c) Respiratory droplets
d) Tick bites

6. The first filovirus hemorrhagic fever outbreaks occurred among laboratory workers in Germany, the infection developed after handling imported African green monkeys. Name the virus isolated from the animal that caused the outbreak of hemorrhagic fever?

a) Lassa virus

b) Ebola virus

c) Marburg virus

d) Zika virus 

 7. A 38 year old female farmer residing in rural village of West Africa arrives at a local healthcare clinic with high fever, with a temperature of 103°F (40°C). She reports feeling weak and fatigued, she also experiences severe joint and muscle pain throughout her body. She complains of persistent nausea and vomiting with abdominal pain, and appears confused and disoriented, with slurred speech.

Upon examination by the healthcare team, the woman has an elevated heart rate (tachycardia) and low blood pressure (hypotension). She has widespread petechiae and ecchymoses (bruising) on her skin, especially on her limbs and trunk.

There is active bleeding from her gums and a swollen, congested appearance of the conjunctiva. Palpation of the abdomen reveals an enlarged liver (hepatomegaly). 

Laboratory tests are performed at the local clinic, complete blood count (CBC) shows low hemoglobin, decreased platelet count and decreased white blood cells count. Liver Function Tests showed elevated liver enzymes (aspartate aminotransferase and alanine aminotransferase). Based on the clinical presentation and limited available laboratory results, the healthcare team suspects a hemorrhagic fever.

What is the most likely mode of transmission for the suspected hemorrhagic fever?

a) Airborne transmission

b) Direct contact with infected animals

c) Foodborne transmission

d) Person-to-person transmission

8. Which of the following clinical findings is NOT typically associated with hemorrhagic fevers?

a) Clear sensorium and alertness

b) High fever

c) Joint and muscle pain

d) Petechiae and ecchymoses

9. Which laboratory finding is commonly seen in patients with hemorrhagic fevers?

a) Elevated hemoglobin levels

b) Low liver enzyme levels

c) Prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT)

d) Normal platelet counts

10. 

Answers with Explanation:

1. d) West Africa. Lassa fever (first detected in Lassa, Nigeria) is endemic to West Africa, with Nigeria being a particularly affected country.

2. c) Mosquitoes. The virus is transmitted to humans through the bite of infected female Aedes and Haemagogus species mosquitoes.

3. b) Dengue Hemorrhagic Fever. Severe dengue, characterized by hemorrhagic symptoms and shock, is referred to as Dengue Hemorrhagic Fever (DHF). 

4. a) By contact with infected rodents. Marburg virus is believed to originate in fruit bats but can be transmitted to humans through contact with infected rodents or their bodily fluids, such as blood, urine, or feces. 
5. d) Tick bites. CCHF is primarily transmitted to humans through the bite of infected ticks, it can also be transmitted through direct contact with the blood and tissues of infected animals. 

6. c) Marburg virus. It comes under a filovirus family and was first isolated from the African green monkeys. It is the most pathogenic of the hemorrhagic fever viruses.

7. b) Direct contact with infected animals. The viruses causing hemorrhagic fever commonly found in West Africa, such as Lassa fever are often zoonotic, meaning they are transmitted from animals to humans. In this case, the woman may have had close contact with rodents or their excreta, which could have exposed her to the virus.

8. a) Clear sensorium and alertness. As the infection progresses in viral hemorrhagic fever, patients may experience altered mental status, confusion, and even coma. 

9. c) Prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT).

The PT and aPTT tests measure the time it takes for the blood to clot in response to specific clotting factors and activators. These tests can indicate underlying coagulation disorders or bleeding tendencies usually seen in hemorrhagic fevers.

10. 

What causes viral hemorrhagic fevers?

These illnesses are caused by viruses from 4 groups:

• Arenaviruses
• Filoviruses
• Bunyaviruses
• Flaviviruses

These viruses infect insects or rodents. You can become infected from exposure to the body, body fluids, or the droppings of an infected rodent or through an insect bite, usually from a mosquito or tick. Some of the viruses  also spread from person to person. Viruses can also be spread if you crush an infected tick. 

Reference: https://www.hopkinsmedicine.org/health/conditions-and-diseases/viral-hemorrhagic-fevers