Which of the following is the vector for scrub typhus?

Appeared in: NIA - 29 January 2023

Explanation

Scrub typhus is an infectious disease caused by the bacterium Orientia tsutsugamushi.
The disease is transmitted to humans through the bite of infected larval mites of the family Trombiculidae, commonly known as chiggers.
These mites thrive in areas with scrub vegetation, which gives the disease its name.
The presence of an eschar (a dark, necrotic sore) at the bite site is a classic diagnostic clue.

Option A: Ticks are vectors for a different group of rickettsial diseases.
Option B: Lice are responsible for transmitting epidemic typhus, not scrub typhus.
Option C: Fleas are the vectors for endemic typhus, also known as murine typhus.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Identification of the specific arthropod vector for scrub typhus as background academic context rather than a clinical decision trigger.
A key nursing responsibility is to obtain a thorough patient history, including environmental and geographic exposures. Asking a febrile patient about recent travel to rural or scrubby areas can be a vital clue for diagnosing scrub typhus.
Early recognition and suspicion of scrub typhus are critical, as prompt administration of doxycycline can be life-saving and prevent severe complications like pneumonitis, meningoencephalitis, or multi-organ failure.
What if? If a patient presented with fever and a rash that started on the wrists and ankles after a hiking trip in North America, the nurse should have a higher suspicion for a tick-borne illness like Rocky Mountain Spotted Fever, rather than scrub typhus.

How to Approach the Question

This is a factual recall question that tests your knowledge of infectious diseases and their vectors.
First, identify the key terms in the question: 'vector' and 'scrub typhus'.
Systematically review the options, recalling the primary diseases associated with each arthropod.
Recall that 'scrub' in scrub typhus refers to the vegetation where the vector lives.
Associate 'Mite (chigger)' with scrub typhus.
Eliminate the other options by linking them to the diseases they transmit: Tick (Rocky Mountain Spotted Fever), Louse (Epidemic Typhus), and Flea (Endemic Typhus).

Concept Tested & Keywords

Concept Tested: Identification of the specific arthropod vector for scrub typhus.
Stem keywords: vector, scrub typhus
Lead-in keywords: Which

QHQsbu4agcZbjbnmj-Fq-z

E6 Medicine Harrison 22e Part 2 p. 1634-1636

E6 Medicine Davidson Principles Practice 24e p. 290-292

Practise the full NIA - 29 January 2023

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