TYPHUSBY TIM WAER

What is Typhus? Chills Cough High Fever Joint Pain Low BP Severe Headache/Muscle Pain Stupor Delirium Rash that begins on chest and spreads to limbs

(but not palms of hands or soles of feet)

What causes Typhus? Rickettsia prowazekii:

epidemic typhus Rickettsia typhi : endemic

(murine) typhus

Gram (-), non-motile, obligate intracellular parasite, aerobic bacteria

Fun Fact: Rickettsia prowazekii and the origin of mitochondria

Andersson et al (1998)Similar functional

profile of genome to mitochondria

Similar ATP production mechs

Possible insight into endosymbiosis

History of Typhus Commonly found in

prisons/crowded areas

Lends to its common name of “Jail Fever”

Where Does Typhus Occur?

How Does Typhus Spread?

Two modes of transmission:Epidemic typhus – Lice to humansEndemic typhus – Fleas to humans

Rickettsia-Host Cell Interaction Entry:

Interaction with Outer Membrane Protiens

Phagocytosis

Escape from Phagosome and Spread to Other Cells

Lysing of Phagosomal Membrane

Divide by Binary Fission

Spread due to burst of cell

Lack Actin-Polymerization machinery

Natural Defense and Rickettsial Survival

When Things Go Bad

Diagnosis Should be made

based on clinical findings

Complete blood count to check for anemia/low platelets

Test for increased levels of typhus antibodies

Treatment Easily treated with a

mix of broad-spectrum antibiotics

Most common include doxycycline, tetracycline and chloramphenicol.

Originally, vaccine dangerous to produce, now just not worth it

Prognosis Infrequent relapses Without treatment, death resulted in 10-

60% of cases for epidemic typhus <2% for endemic typhus Prompt treatment leads to prompt

recovery

Prevention Good Hygiene

Avoid areas where one may encounter rats/fleas and lice.

Bathe regularlyUse insecticidesWash clothes regularly

References Anderson et al. “The genome sequence of Rickettsia

prowazekii and the origin of mitochondria”. Nature 396. (1998) pg 133-140.

Immunopaedia.org, 2010. Web. 4 April 2012. http://www.immunopaedia.org.za/index.php?id=257

Mayer, Gene. Microbiology and Immunology. Columbia, SC: The Board of Trustees of the University of South Carolina, 2010.

Parola, Philippe and Didier Raoult. Rickketsial Diseases. Informa Healthcare, 2007.

“Rickketsia”. Wikipedia, The Free Encyclopedia. Wikimedia Foundation Inc. 21 Feb 2012. Web. 4 April 2012.

“Typhus”. Wikipedia, The Free Encyclopedia. Wikimedia Foundation, Inc. 30 March 2012. Web. 4 April 2012.