Nokea
Which of the following viruses belong to family Arenaviridae?
- A. Lassa virus
- B. Crimean-Congo hemorrhagic fever virus
- C. Rabies virus
- D. Epstein-Barr virus
Correct Answer: A
Rationale: Step-by-step rationale:
1. Arenaviridae family includes viruses with a segmented genome.
2. Lassa virus has a segmented genome, placing it in the Arenaviridae family.
3. Crimean-Congo hemorrhagic fever virus belongs to the Nairoviridae family, not Arenaviridae.
4. Rabies virus belongs to the Rhabdoviridae family, not Arenaviridae.
5. Epstein-Barr virus belongs to the Herpesviridae family, not Arenaviridae.
Summary:
A: Lassa virus is correct because it has a segmented genome, characteristic of Arenaviridae.
B, C, D: Crimean-Congo hemorrhagic fever virus, Rabies virus, and Epstein-Barr virus belong to different virus families, not Arenaviridae.
You may also like to solve these questions
The cytopathic effect caused by viruses of family paramyxoviridae looks like:
- A. Fine grained degeneration
- B. Giant multinucleated cells syncytia
- C. Large cell degeneration with grape clustering of cells
- D. Do not provoke a cytopathic effect on cell cultures
Correct Answer: B
Rationale: Rationale: The correct answer is B. Viruses of the family Paramyxoviridae cause the formation of giant multinucleated cells called syncytia. This occurs when infected cells fuse together, resulting in large, multinucleated structures. This is a characteristic cytopathic effect of paramyxoviruses.
Summary:
A: Fine grained degeneration is not typically seen in paramyxovirus infections.
C: Large cell degeneration with grape clustering of cells is not a typical cytopathic effect of paramyxoviruses.
D: Paramyxoviruses do provoke a cytopathic effect, so this statement is incorrect.
Bacillary dysentery is also called:
- A. salmonellosis
- B. shigellosis
- C. typhoid fever
- D. campylobacteriosis
Correct Answer: B
Rationale: Bacillary dysentery is caused by the bacterium Shigella, hence it is also known as shigellosis. Shigella is the primary pathogen responsible for this infectious disease, leading to severe diarrhea with blood and mucus. Salmonellosis (A) is caused by Salmonella bacteria, not Shigella. Typhoid fever (C) is caused by Salmonella typhi, not Shigella. Campylobacteriosis (D) is caused by Campylobacter bacteria, not Shigella. Therefore, the correct answer is B because Shigella is the specific bacterium associated with bacillary dysentery.
The primary stage of syphilis is usually manifested as:
- A. Diffuse maculopapular rush
- B. Purulent exudation from the urethra
- C. Syphilitic granulomas (gummas)
- D. Non-tender chancre (ulcus durum)
Correct Answer: D
Rationale: The correct answer is D: Non-tender chancre (ulcus durum). In the primary stage of syphilis, an individual typically develops a painless ulcer known as a chancre at the site of infection. This ulcer is usually firm, round, and clean with well-defined borders. It is important to note that it is non-tender, which distinguishes it from other skin conditions. This characteristic helps healthcare providers differentiate syphilis from other sexually transmitted infections.
Explanation for other choices:
A: Diffuse maculopapular rash - This is more commonly associated with secondary syphilis.
B: Purulent exudation from the urethra - This is not a typical presentation of primary syphilis.
C: Syphilitic granulomas (gummas) - Gummas typically develop in the tertiary stage of syphilis, not in the primary stage.
Hepatitis B infection may present with:
- A. Jaundice
- B. Elevated serum aminotransferase levels
- C. No symptoms
- D. All of the above
Correct Answer: D
Rationale: The correct answer is D: All of the above. Hepatitis B infection can present with jaundice due to liver inflammation, elevated serum aminotransferase levels due to liver damage, and sometimes no symptoms in the acute phase. This comprehensive presentation covers the spectrum of possible clinical manifestations of hepatitis B infection. Choices A and B are correct as they are common manifestations of hepatitis B infection. Choice C is incorrect as hepatitis B infection can indeed present with symptoms, making option D the most appropriate choice.
A 65-year-old patient with fever and a productive cough had a sputum sample revealing Gram-negative, non-motile, rod-shaped bacteria. What is the most likely causative agent?
- A. Klebsiella pneumoniae
- B. Pseudomonas aeruginosa
- C. Escherichia coli
- D. Haemophilus influenzae
Correct Answer: A
Rationale: The correct answer is A: Klebsiella pneumoniae. This bacterium is commonly associated with pneumonia in elderly patients. Klebsiella pneumoniae is a Gram-negative, non-motile, rod-shaped bacterium that frequently causes pneumonia in individuals with underlying health conditions. It is known for its ability to produce a distinctive mucoid capsule. Pseudomonas aeruginosa (B) is more commonly associated with hospital-acquired infections, particularly in immunocompromised individuals. Escherichia coli (C) is a common cause of urinary tract infections but is less likely in this case due to the symptoms and sputum sample results. Haemophilus influenzae (D) is another common respiratory pathogen, but in this scenario, Klebsiella pneumoniae is the most likely causative agent based on the patient's age, symptoms, and the characteristics of the bacteria described in the sputum sample.