Rickettsiosis
Encyclopedia
A rickettsiosis is a disease caused by intracellular bacteria.
It has been predicted that global warming
may lead to greater incidence.
group (SPG) and typhus
group (TG).
In the past, rickettsioses were considered to be caused by species of Rickettsia
. However, scrub typhus
is still considered a rickettsiosis, even though the causative organism has been reclassified from Rickettsia tsutsugamushi to Orientia tsutsugamushi
.
Examples of rickettsioses include typhus
, both endemic and epidemic, Rocky Mountain spotted fever
, and Rickettsialpox
.
Organisms involved include Rickettsia parkeri.
Many new causative organisms have been identified in the last few decades.
Most are in the genus Rickettsia
, but scrub typhus
is in the genus Orientia
.
It has been predicted that global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
may lead to greater incidence.
Examples and causative organisms
Rickettsioses can be divided into a spotted feverSpotted fever
A spotted fever is a type of tick-borne disease which presents on the skin.Types include:* Mediterranean spotted fever* Rocky Mountain spotted fever* Queensland tick typhus...
group (SPG) and typhus
Typhus
Epidemic typhus is a form of typhus so named because the disease often causes epidemics following wars and natural disasters...
group (TG).
In the past, rickettsioses were considered to be caused by species of Rickettsia
Rickettsia
Rickettsia is a genus of non-motile, Gram-negative, non-sporeforming, highly pleomorphic bacteria that can present as cocci , rods or thread-like . Being obligate intracellular parasites, the Rickettsia survival depends on entry, growth, and replication within the cytoplasm of eukaryotic host cells...
. However, scrub typhus
Scrub typhus
Scrub typhus or Bush typhus is a form of typhus caused by Orientia tsutsugamushi first isolated and identified in 1930 in Japan., accessdate: 16 October 2011...
is still considered a rickettsiosis, even though the causative organism has been reclassified from Rickettsia tsutsugamushi to Orientia tsutsugamushi
Orientia tsutsugamushi
Orientia tsutsugamushi is the causative organism of scrub typhus, and the natural vector and reservoir is probably trombiculid mites ....
.
Examples of rickettsioses include typhus
Typhus
Epidemic typhus is a form of typhus so named because the disease often causes epidemics following wars and natural disasters...
, both endemic and epidemic, Rocky Mountain spotted fever
Rocky Mountain spotted fever
Rocky Mountain spotted fever is the most lethal and most frequently reported rickettsial illness in the United States. It has been diagnosed throughout the Americas. Some synonyms for Rocky Mountain spotted fever in other countries include “tick typhus,” “Tobia fever” , “São Paulo fever” or “febre...
, and Rickettsialpox
Rickettsialpox
Rickettsialpox is an illness caused by bacteria of the Rickettsia genus . Physician Robert Huebner and self-trained entomologist Charles Pomerantz played major roles in identifying the etiology of the disease after an outbreak in 1946 in a New York City apartment complex, documented in medical...
.
Organisms involved include Rickettsia parkeri.
Many new causative organisms have been identified in the last few decades.
Most are in the genus Rickettsia
Rickettsia
Rickettsia is a genus of non-motile, Gram-negative, non-sporeforming, highly pleomorphic bacteria that can present as cocci , rods or thread-like . Being obligate intracellular parasites, the Rickettsia survival depends on entry, growth, and replication within the cytoplasm of eukaryotic host cells...
, but scrub typhus
Scrub typhus
Scrub typhus or Bush typhus is a form of typhus caused by Orientia tsutsugamushi first isolated and identified in 1930 in Japan., accessdate: 16 October 2011...
is in the genus Orientia
Orientia
Orientia is a genus of bacteria in family Rickettsiaceae.They are obligate intracellular gram negative bacteria found in insects and mammals. They are spread through the bites or feces of infected insects.One species is Orientia tsutsugamushi....
.