Revised July 1, 2020 Staphylococcus aureus is a highly successful opportunistic pathogen. It is a frequent colonizer of the skin and mucosa of humans and animals (it is present in the anterior nares of up to 30% of the healthy…
Bacteria, the oldest forms of life on earth, are remarkably diverse and exist in astounding numbers. Diseases caused by bacteria include some of the most common infections in the world and some of the most important human scourges, past, present,…
Until 1987, infections by members of the family Anaplasmataceae, including the genera Ehrlichia, Anaplasma, and Neorickettsia, were known mainly as veterinary diseases ( Table 192.1 ). Canine ehrlichiosis was first described in 1935 by Donatien and Lestoquard in Algeria. This…
History The earliest clinical reports of possible scrub typhus date back to the Chinese manual Zhouhofang in 313 bc . In 1810 the association of a febrile illness with mite transmission was made in the Niigata Prefecture in Japan, which…
In 1922, Hone first described human infections “closely resembling typhus fever.” Since 1926, when Maxcy successfully identified murine typhus as a distinct clinical and epidemiologic entity, and 1931, when Dyer isolated a new typhus group named Rickettsia from rats and…
Rickettsia prowazekii is the only rickettsial species that can cause devastating, naturally occurring epidemics capable of killing a substantial proportion of human populations infested with body lice. Epidemics are associated with conditions that prevent bathing and washing of clothes in…
Q fever remains an intriguing disease despite being studied for more than 80 years. Molecular diagnostics and genomic analysis are adding to our understanding of the disease. The large outbreak in the Netherlands, other outbreaks, and longitudinal studies from France…
Rickettsialpox is a worldwide mite-borne rickettsiosis presenting as a febrile and vesicular eruption. It is caused by Rickettsia akari, associated with mice, and transmitted by its ectoparasite, the mite Liponyssoides sanguineus. Etiology Rickettsia akari is classified among spotted fever group…
The spotted fevers comprise a large group of tick-, mite-, and flea-borne zoonotic infections that are caused by closely related rickettsiae. These include Rocky Mountain spotted fever (RMSF), boutonneuse fever, African tick bite fever, North Asian tick typhus, lymphangitis-associated rickettsiosis,…
Bacteriology Originally, all small gram-negative bacteria, associated (or not) with arthropods and strictly or facultatively intracellular, were considered Rickettsiaceae. The advent of 16S ribosomal RNA gene sequencing and phylogeny has deeply challenged this classification. The controversy has centered on how…