Rickettsia sibirica

Rickettsia sibirica is a species of bacteria in the genus Rickettsia. It is the causative agent of North Asian tick typhus, also known as Siberian tick typhus, a disease transmitted by ticks.

Taxonomy

Rickettsia sibirica belongs to the genus Rickettsia, which is part of the family Rickettsiaceae in the order Rickettsiales. The genus Rickettsia is divided into four groups: spotted fever, typhus, ancestral, and transitional. Rickettsia sibirica is part of the spotted fever group.

Morphology

Like all Rickettsia species, Rickettsia sibirica is a small, rod-shaped bacterium. It is Gram-negative, meaning it does not retain the crystal violet stain used in the Gram stain procedure.

Pathogenesis

Rickettsia sibirica is the causative agent of North Asian tick typhus. The bacterium is transmitted to humans through the bite of an infected tick. Once in the human body, the bacteria invade the endothelial cells lining the blood vessels, causing symptoms such as fever, headache, and rash.

Epidemiology

North Asian tick typhus is endemic in many parts of Asia, including Siberia and Mongolia. The disease is most commonly transmitted by the Dermacentor species of ticks.

Treatment and Prevention

The antibiotic doxycycline is the treatment of choice for North Asian tick typhus. Prevention strategies include avoiding tick-infested areas and using insect repellents.

See Also

• Rickettsia rickettsii
• Rickettsia conorii
• Rickettsia africae