Rickettsia prowazekii

microorganism

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Last updated

July 13, 2026

Quick Summary

Rickettsia prowazekii is a bacterium responsible for epidemic typhus, a serious infectious disease. This bacterium is a type of rickettsia, which are microorganisms that fall between viruses and bacteria in size and can only multiply within host cells.12

R. prowazekii is transmitted to humans through the bite of an infected body louse (Pediculus humanus humanus). Humans are the primary host for this bacterium. Infection can lead to symptoms such as headache, fever, chills, and a rash. Without treatment, epidemic typhus can cause severe complications, including organ damage and potentially death. Antibiotics like doxycycline are effective treatments.31

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typhus
Causes, symptoms, & Treatment
…is caused by the bacterium Rickettsia prowazekii and is conveyed from person to person by the body louse, Pediculus humanus humanus. The louse is infected by feeding with its powerful sucking mouth on a person who has the disease. As the louse sucks the person’s blood, rickettsiae pass into the…
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…is caused by the bacterium Rickettsia prowazekii and is conveyed from person to person by the body louse, Pediculus humanus humanus. The louse is infected by feeding with its powerful sucking mouth on a person who has the disease. As the louse sucks the person’s blood, rickettsiae pass into the…
Read More