Author
Wilson, William - Bill | |
ROMITO, MARCO - Onderstepoort Veterinary Institute | |
Jasperson, Dane | |
WEINGARTL, HANA - Canadian Food Inspection Agency | |
BINEPAL, YATINDER - Kenya Agricultural Research Institute | |
MALULEKE, MOABI - Onderstepoort Veterinary Institute | |
WALLACE, DAVID - Onderstepoort Veterinary Institute | |
JANSEN VAN VUREN, PETRUS - National Institute For Communicable Diseases (NICD) | |
PAWESKA, JANUSZ - National Institute For Communicable Diseases (NICD) |
Submitted to: Journal of Virological Methods
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/3/2013 Publication Date: 7/22/2013 Citation: Wilson, W.C., Romito, M., Jasperson, D.C., Weingartl, H., Binepal, Y.S., Maluleke, M.R., Wallace, D., Jansen Van Vuren, P., Paweska, J.T. 2013. Development of a Rift Valley fever real-time RT-PCR assay that can detect all three genome segments. Journal of Virological Methods. 193:426-431. DOI: 10.1016/j.jviromet.2013.07.006 Interpretive Summary: Rift Valley fever in Africa have had devastating effects on livestock and human health. In addition, this disease is a food security issue for endemic African countries. There is growing concern for the potential introduction of RVF into non-endemic countries. This study describes the development of a new assay based on genome amplification that is more robust than previous assays due to multiple gene targets and include an amplification control to detect inhibitors that could affect the assay. The assay also includes a differentiate infected from vaccinated (DIVA) compatible marker for some RVF vaccines, which is useful for RVF endemic countries but especially important in non-endemic countries Technical Abstract: Outbreaks of Rift Valley fever in Kenya, Madagascar, Mauritania, and South Africa had devastating effects on livestock and human health. In addition, this disease is a food security issue for endemic countries. There is growing concern for the potential introduction of RVF into non-endemic countries. A number of single-gene target amplification assays have been developed for the rapid detection of RVF viral RNA. We describe the development of an improved amplification assay that includes two confirmatory target RNA segments (L and M) and a third target gene, NSs, which is deleted in the Clone 13 commercial vaccine and other candidate vaccines. The assay also contains an exogenous RNA control for detection of amplification inhibitors. The assay was initially evaluated with samples from experimentally infected animals, after which clinical veterinary and human samples from endemic countries were tested for further evaluation. The assay has a sensitivity range of 66.7-100% and a specificity of 92.0-100% depending on the comparison. The assay has an overall sensitivity of 92.5%, specificity of 95% and a positive predictive value of 98.7%. The single-tube assay provides confirmation of the presence of RVFV RNA for improved confidence in diagnostic results and a “differentiate infected from vaccinated animals” (DIVA)-compatible marker for RVFV NSs- deleted vaccines, which is useful for RVF endemic countries, but especially important in non-endemic countries. |