Paul N. NewtonJean Marc RolainBouachanh RasachakMayfong MayxayKhamtanh VathanathamPiseth SengRattanaphone PhetsouvanhTe ThammavongJamaayah ZahidiYupin SuputtamongkolBounkong SyhavongDidier RaoultMahosot HospitalUniversite de la Mediterranee Aix-Marseille IINuffield Department of Clinical MedicineUniversity of Health SciencesLiving Aquatic Resources Research Centre (LARReC)Lao Red CrossInstitute for Medical Research Kuala LumpurMahidol University2018-09-132018-09-132009-08-01American Journal of Tropical Medicine and Hygiene. Vol.81, No.2 (2009), 190-194000296372-s2.0-68549139017https://repository.li.mahidol.ac.th/handle/20.500.14594/27687Neorickettsia sennetsu has been described from Japan and Malaysia, causing a largely forgotten infectious mononucleosis-like disease. Because it is believed to be contracted from eating raw fish, frequently consumed in the Lao PDR, we looked for evidence of N. sennetsu among Lao patients and fish. A buffy coat from 1 of 91 patients with undifferentiated fever was positive by 16S rRNA amplification and sequencing and real-time polymerase chain reactions (PCR) targeting two N. sennetsu genes. Lao blood donors and patients with fever, hepatitis, or jaundice (N = 1,132) had a high prevalence (17%) of immunofluorescence assay IgG anti-N. sennetsu antibodies compared with 4% and 0% from febrile patients (N = 848) in Thailand and Malaysia, respectively. We found N. sennetsu DNA by PCR, for the first time, in a fish (Anabas testudineus). These data suggest that sennetsu may be an under-recognized cause of fever and are consistent with the hypothesis that it may be contracted from eating raw fish. Copyright © 2009 by The American Society of Tropical Medicine and Hygiene.Mahidol UniversityImmunology and MicrobiologyMedicineArticleSCOPUS