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 humans Endemic 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 % 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 regularly Use insecticides Wash clothes regularly

References  Anderson et al. “The genome sequence of Rickettsia prowazekii and the origin of mitochondria”. Nature 396. (1998) pg  Immunopaedia.org, Web. 4 April  Mayer, Gene. Microbiology and Immunology. Columbia, SC: The Board of Trustees of the University of South Carolina,  Parola, Philippe and Didier Raoult. Rickketsial Diseases. Informa Healthcare,  “Rickketsia”. Wikipedia, The Free Encyclopedia. Wikimedia Foundation Inc. 21 Feb Web. 4 April  “Typhus”. Wikipedia, The Free Encyclopedia. Wikimedia Foundation, Inc. 30 March Web. 4 April 2012.