North Asian tick fever, also known as North Asian tick typhus or Siberian tick typhus, is a tick-borne spotted fever rickettsiosis. It is transmitted to humans by the bite of a tick infected with Rickettsia sibirica, a species broadly distributed throughout northern and central Asia, particularly China, Mongolia, and Russia. Known principal vectors include Dermacentor nuttalli, Dermacentor silvarum, Dermacentor pictus, Dermacentor marginatus, Haemaphysalis concinna, and Haemaphysalis punctata. Rodents serve as the animal reservoirs.

The peak season of disease transmission is in the spring and summer months of March to October. Following a 4- to 7-day incubation period, an eschar forms at the site of inoculation and high fever develops. Regional lymphadenopathy with drainage may occur. Other common associated symptoms include severe headache, myalgia, and gastrointestinal disturbances for 6-10 months if no treatment is initiated. Patients could develop a maculopapular rash 2-4 days after the onset of symptoms.

Prognosis is good. Rare cases with neurological complications have been reported; however, most cases resolve without long-term complications.