Submitted to: American Society of Tropical Medicine and Hygiene
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/29/2007
Publication Date: 4/2/2008
Citation: Paddock, C.D., Fernandez, S., Echenique, G.A., Sumner, J.W., Reeves, W.K., Zaki, S.R., Remondegui, C.E. 2008. Rocky Mountain Spotted Fever in Argentina. American Society of Tropical Medicine and Hygiene. 78, 687-692.
Interpretive Summary: We describe the first molecular detection of Rocky Mountain spotted fever (RMSF) from ticks collected in Argentina from the site of fatal cases of RMSF. DNA from the bacteria that causes RMSF was detected in ticks and tissue from one fourth patients who died during the outbreak. Cases were also verified by immunology.
Technical Abstract: We describe the first molecular confirmation of Rickettsia rickettsii, the cause of Rocky Mountain spotted fever (RMSF), from a tick vector, Amblyomma cajennense, and from a cluster of fatal spotted fever cases in Argentina. Questing A. cajennense ticks were collected at or near sites of presumed or confirmed cases of spotted fever rickettsiosis in Jujuy Province and evaluated by polymerase chain reaction assays for spotted fever group rickettsiae. DNA of R. rickettsii was amplified from a pool of A. cajennense ticks and from tissues of one of four patients who died during 2003–2004 after illnesses characterized by high fever, severe headache, myalgias, and petechial rash. The diagnosis of spotted fever rickettsiosis was confirmed in the other patients by indirect immunofluorescence antibody and immunohistochemical staining techniques. These findings show the existence of RMSF in Argentina and emphasize the need for clinicians throughout the Americas to consider RMSF in patients with febrile rash illnesses.