Emerg Infect DiseidEmerging Infectious Diseases1080-60401080-6059Centers for Disease Control109059742640907Research ArticleEvidence of Rickettsia helvetica infection in humans, eastern France.FournierP. E.GrunnenbergerF.JaulhacB.GastingerG.RaoultD.Université de la Méditerranée, Marseille, France.Jul-Aug200064389392

A 37-year-old man living in eastern France seroconverted to Rickettsia helvetica in August 1997, 4 weeks after the onset of an unexplained febrile illness. Results of a serosurvey of forest workers from the area where the patient lived showed a 9.2% seroprevalence against R. helvetica. This organism may pose a threat for populations exposed to Ixodes ricinus ticks.