title: Superiority of West Nile Virus RNA Detection in Whole Blood for Diagnosis of Acute Infection.
abstract: The current diagnosis of West Nile virus (WNV) infection is primarily based on serology, since molecular identification of WNV RNA is unreliable due to the short viremia and absence of detectable virus in cerebrospinal fluid (CSF). Recent studies have shown that WNV RNA can be detected in urine for a longer period and at higher concentrations than in plasma. In this study, we examined the presence of WNV RNA in serum, plasma, whole-blood, CSF, and urine samples obtained from patients diagnosed with acute WNV infection during an outbreak which occurred in Israel in 2015. Our results demonstrate that 33 of 38 WNV patients had detectable WNV RNA in whole blood at the time of diagnosis, a higher rate than in any of the other sample types tested. Overall, whole blood was superior to all other samples, with 86.8% sensitivity, 100% specificity, 100% positive predictive value, and 83.9% negative predictive value. Interestingly, WNV viral load in urine was higher than in whole blood, CSF, serum, and plasma despite the lower sensitivity than that of whole blood. This study establishes the utility of whole blood in the routine diagnosis of acute WNV infection and suggests that it may provide the highest sensitivity for WNV RNA detection in suspected cases.
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel Yaniv.lustig@sheba.health.gov.il.
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Lustig
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel.
authors.forename: Batya
authors.initials: B
authors.lastname: Mannasse
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel.
authors.forename: Ravit
authors.initials: R
authors.lastname: Koren
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel.
authors.forename: Shiri
authors.initials: S
authors.lastname: Katz-Likvornik
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Musa
authors.initials: M
authors.lastname: Hindiyeh
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Mandelboim
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel.
authors.forename: Sara
authors.initials: S
authors.lastname: Dovrat
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel.
authors.forename: Danit
authors.initials: D
authors.lastname: Sofer
authors.affiliation: Central Virology Laboratory, Ministry of Health, Tel HaShomer, Israel School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Ella
authors.initials: E
authors.lastname: Mendelson
mesh_terms: D001769:Blood / Q000821:virology*; D002555:Cerebrospinal Fluid / Q000821:virology; D006801:Humans; D007557:Israel; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D011237:Predictive Value of Tests; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D014556:Urine / Q000821:virology; D014901:West Nile Fever / Q000175:diagnosis*; D014902:West Nile virus / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D012367:RNA, Viral