Question

All of the following statements about scrub typhus are true, except:

• A. Caused by Orientia tsutsugamushi
• B. Mites act as reservoirs
• C. Transmitted when adult mites feed on hosts
• D. Tetracycline is the drug of choice

Hint:

Only the larval chigger bites, not the adult mite.

Answer 1

The Correct Option is C

To answer this except item, recall the life cycle of the mite vector. Scrub typhus is a rickettsial illness from Orientia tsutsugamushi, confirming the first option. The trombiculid mite keeps the organism going across generations through transovarial passage, so it serves as the reservoir as well as the vector, validating the second option. The crucial point is that only the immature larval form, the chigger, actually bites and feeds on a host and thereby delivers the organism. The grown adult mite lives free in the soil and does not take a blood meal from humans, so claiming that adult mites transmit by feeding is the false statement. Doxycycline or tetracycline remains the treatment of choice, so the last option is correct. The exception is the line about adult mites feeding on hosts. $$\boxed{\text{Transmitted when adult mites feed on hosts (false)}}$$