NCIt definition : A gram-negative bacterial infection caused by Rickettsia prowazekii. It is spread
by lice infected with the bacteria. Signs and symptoms include sudden headache, generalized
muscle pain, malaise, and macular skin lesions. The infection may affect the central
nervous system causing encephalitis.;
Alternative definition : NICHD: An infection that is caused by Rickettsia prowazekii, which is transmitted
to humans from infected lice; manifestations include sudden headache, generalized
muscle pain, malaise, macular skin lesions, and encephalitis.;