title: A real-time reverse transcription loop-mediated isothermal amplification assay for the rapid detection of yellow fever virus.
abstract: Yellow fever, a mosquito-borne disease, is an important viral hemorrhagic fever in Africa and South America where it is endemic. Detection of yellow fever virus (YFV) in Africa remains a challenge due to a lack of highly specific tests. The aim of this study was to develop and optimize a rapid detection reverse transcription loop-mediated isothermal amplification (RT-LAMP) for YFV. The RT-LAMP was done isothermally at 62 °C using a real-time turbidimeter that allowed detection within 1h. Specificity of the RT-LAMP was determined using RNA from flaviviruses and other related viruses where only YFV RNA was detected: West Nile virus, dengue viruses, Japanese encephalitis virus, Rift Valley fever virus, and chikungunya virus. In addition, equal sensitivity was also observed when the RT-LAMP and the real-time RT-PCR were compared using YFV-spiked human serum samples with a detection limit of 0.29 PFU/ml. Two Kenyan YFV wild strains showed an equal detection limit as the vaccine strain 17D in this study. The RT-LAMP reduced the time of reaction from 3h to 1h and increased sensitivity tenfold compared to RT-PCR. Therefore, this test offers a simple, rapid and reliable diagnostic tool for yellow fever when there are outbreaks of acute hemorrhagic fever in Kenya and other African countries.
authors.affiliation: Institute of Tropical Medicine and Infectious Diseases, Jomo Kenyatta University of Agriculture and Technology, Juja 62000-00200, Kenya.
authors.forename: Allan ole
authors.initials: Ao
authors.lastname: Kwallah
authors.forename: Shingo
authors.initials: S
authors.lastname: Inoue
authors.forename: Anne W T
authors.initials: AW
authors.lastname: Muigai
authors.forename: Toru
authors.initials: T
authors.lastname: Kubo
authors.forename: Rosemary
authors.initials: R
authors.lastname: Sang
authors.forename: Kouichi
authors.initials: K
authors.lastname: Morita
authors.forename: Matilu
authors.initials: M
authors.lastname: Mwau
mesh_terms: D000349:Africa; D006801:Humans; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D048348:Reverse Transcription; D012680:Sensitivity and Specificity; D013020:South America; D013696:Temperature; D013997:Time Factors; D015004:Yellow Fever / Q000175:diagnosis* / Q000821:virology; D015005:Yellow fever virus / Q000302:isolation & purification*
keywords: NS1; RT-LAMP; YFV