Roundworm

Tsutsugamushi disease, also known as scrub typhus, is an acute infectious disease caused by Rickettsia tsutsugamushi. It is a natural epidemic disease. The main source of infection is rodents, and the transmission vector is chigger larva. Its clinical features are acute onset, fever, rash, lymphadenopathy, hepatosplenomegaly, and eschar at the bite of chigger mites. The ancient Chinese doctor Jin Gehong mentioned that the disease was prevalent in southern China more than 1600 years ago, and called it "sand fever".