Which animal is an amplifier of Japanese encephalitis?

Appeared in: Tripura CHO - 2021

Explanation

Pigs are the primary amplifying hosts for the Japanese Encephalitis (JE) virus.
An amplifying host is an animal where the virus replicates to very high levels, leading to high viremia (a large amount of virus in the bloodstream).
This high concentration of the virus in pigs' blood allows mosquitoes (the vectors) to easily acquire the virus when they feed, thus amplifying the transmission to other animals and humans.
Textbooks on preventive medicine explicitly identify pigs as the 'amplifiers' in the JE cycle.

Option A: Cows do not develop high enough levels of the JE virus in their blood to effectively transmit it back to mosquitoes. They are considered incidental or dead-end hosts.
Option B: Monkeys are not significant in the JE transmission cycle.
Option D: Cats have no known role in the natural transmission cycle of the Japanese Encephalitis virus.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Amplifier host in the transmission cycle of Japanese Encephalitis as background academic context rather than a clinical decision trigger.
Understanding that pigs are the main amplifiers for JE is crucial for public health interventions in endemic areas.
Control measures often include advising communities to locate pigsties away from human dwellings and implementing pig vaccination programs to break the transmission cycle.
Patient education by nurses should include vector control measures like using mosquito nets, wearing protective clothing, and eliminating stagnant water sources where mosquitoes breed.

How to Approach the Question

This is a factual recall question testing knowledge of communicable disease epidemiology.
First, identify the key terms in the question: 'amplifier' and 'Japanese encephalitis'.
Recall the definition of an 'amplifier host' in a disease cycle: an organism in which a pathogen (like a virus) multiplies rapidly to high concentrations, increasing the risk of transmission.
Access your knowledge of the specific transmission cycle for Japanese Encephalitis.
Mentally map the key players: Reservoir (birds), Vector (mosquitoes), Amplifier (pigs), and Dead-end host (humans).
Evaluate each option against this known cycle. Cow, Monkey, and Cat are not amplifiers in the JE cycle, making Pig the correct answer.

Concept Tested & Keywords

Concept Tested: Amplifier host in the transmission cycle of Japanese Encephalitis.
Stem keywords: animal, amplifier, Japanese encephalitis
Lead-in keywords: Which
Negative lead-in flag: false

Q8OhXcsYH-jomFob6VPAeB

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart B (pp 202-403 of 604) pp. 148-150, 149-151

E6 Medicine Harrison 22e Part 1 p. 1701-1703

Practise the full Tripura CHO - 2021

Attempt every question from this paper in a timed mock, then review the full solution for each one.