What Diseases Do Chiggers Spread?
What Diseases Do Chiggers Spread?
Chigger larvae can transmit scrub typhus, a zoonotic disease caused by the bacterium *Orientia tsutsugamushi*.
How Scrub Typhus Spreads
- Chigger larvae pick up the pathogen when feeding on wild animals (mainly rodents) that carry *Orientia tsutsugamushi*.
- The pathogen multiplies inside the chigger larva and is transmitted to the next host (person or animal) through its bite.
- After a person is bitten by an infected chigger larva, symptoms appear after an incubation period of 4-21 days (typically 10-14 days).
Classic Symptoms of Scrub Typhus
- High fever -- Sudden onset, temperature reaching 39-40 deg C (102-104 deg F), accompanied by chills.
- Eschar (the telltale sign) -- A black scab forms at the bite site, surrounded by a red halo. It is painless and non-itchy, and is the key diagnostic clue.
- Rash -- A full-body red maculopapular rash appears 3-7 days after the fever starts.
- Systemic symptoms -- Severe headache, muscle aches, fatigue, swollen lymph nodes.
Serious Complications (If Left Untreated)
- Pneumonia, myocarditis
- Meningitis
- Multiple organ failure
- Without treatment, the fatality rate can range from 1% to 30%, depending on the strain and region.
Treatment and Prevention
Scrub typhus responds very well to doxycycline. Early diagnosis and proper treatment are critical. Prevention focuses on outdoor protection (long sleeves and pants, using repellent) and showering and changing clothes promptly after being outdoors.