Trends in the incidence of scrub typhus: the fastest growing vector-borne disease in Korea.

Scrub typhus, also called tsutsugamushi disease, is classified as a Group 3 disease in Korea according to the National Notifiable Diseases Surveillance Systems. It is an infectious disease transmitted to humans through the bite of mites that are infected with an intracellular parasite called Orientia tsutsugamushi (Family: Rickettsiaceae). This study aims to identify the demographic characteristics of the infected cases according to profession, region, gender, and onset period and provide a basic data for prevention and control of the disease in the infected patients. Between 2001 and 2010, 16,741 men (36.3%) and 29,373 women (63.7%) were reported to have been infected with scrub typhus, with men being 1.6 times less infected than women. When classified according to age, it was found that 4421 persons (9.6%) were under 40 years of age; 6601 (13.1%) in their 40s; 9714 (21.1%) in their 50s; 13,067 (28.3%) in 60s; 10,128 (22.0%) in their 70s; and 2723 (5.9%) aged 80 or more. The elderly (60 years or older) represented more than half of the infected cases. When the infections were classified according to region, it was found that the county residents had the major share of infection, with a total of 1583 infected cases (59.85).