[Surveillance of Chiggers Density in the Republic of Korea, 2022]

Scrub typhus is an acute febrile disease in autumn. Scrub typhus is spread to people through bites of infected chiggers (larval mites) with Orientia tsutsugamushi. The symptoms are fever, headache, and sometimes rash. In order to survey occurrence of chiggers in the Republic of Korea, chiggers were collected weekly at 18 locations nationwide from August 24 to December 14 in 2022. The number of chiggers collected per trap was calculated for comparison. The period of increasing of chiggers was hurried by 2 weeks compared to 2021. Moreover, after showing the highest occurrence (week 45), it decreased gradually. Of the total 3,723 chiggers were identified as 18 species in 5 genera. Among them, Leptotrombidium scutellare was the dominant species with 1,418 specimens (37.2%). Given the recent an increase in the number of people working outdoors and aging of the rural population, there is a high concern that the number of scrub typhus patients will increase. Therefore, if it is suspected symtoms after being bitten by a mite, it is important to get diagnosed early. And also, because the pattern of vector occurrence has been effected due to climate change, it is important to monitor for mites continuously.