Rickettsial infections--a threat to travellers?
OBJECTIVE
Recent developments in cell-culture techniques and molecular methods have led to the description of several new rickettsial diseases. An update on these new infections should be of interest to health workers with patients who are international travellers.


RESULTS
Epidemic typhus was reported last year in the United States when an outbreak of murine typhus was recorded in Hawaii. Among spotted fever group rickettsioses, African tick bite fever is now probably the most common rickettsial infection in Africa with numerous cases also reported in international travellers. For the first time the Astrakhan fever rickettsia has been described outside Europe, in a French patient returning from Chad. Similarly, the first case of Rickettsia sibirica mongolotimonae infection in Africa was reported in 2004. Finally, a newly recognized agent of a spotted fever rickettsiosis, Rickettsia parkeri, has been reported in the United States during 2004.


CONCLUSIONS
Because results of serological testing are only presumptive, sophisticated methods are crucial for the diagnosis and description of new rickettsial diseases, especially in atypical cases. Modern diagnostic tools include cross-adsorption assays, Western blot testing, and cell-culture and molecular-biological methods.
Rolain
Jean-Marc
JM
Unité des Rickettsies CNRS UPRES-A 6020, Faculté de Médecine, Université de la Méditerranée, 27, Boulevard Jean Moulin, 13385 Marseille Cedex 05, France.
Jensenius
Mogens
M
Raoult
Didier
D
D000818:Animals; D006801:Humans; D038622:Internationality; D051379:Mice; D012281:Rickettsia / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D012282:Rickettsia Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology*; D014195:Travel