Development of a Usutu virus specific real-time reverse transcription PCR assay based on sequenced strains from Africa and Europe

Nikolay, Birgit; Weidmann, Manfred; Dupressoír, Anne; Faye, Ousmane; Boye, Cheikh Saad Bouh; Diallo, Mawlouth; Sall, Amadou Alpha

doi:10.1016/j.jviromet.2013.08.039

Cited by 56 publications

(55 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Samples were spun down for 10 minutes at 10.000 xg after which Phocine distemper virus (PDV) was added as internal NA extraction control to the supernatant and total NA was extracted from the supernatant using the Roche MagNA Pure. The NA was screened for the presence of USUV using real-time PCRs described by Nicolay et al 44 and Jost et al 45 , in duplex with PDV.…”

Section: Methodsmentioning

confidence: 99%

Genomic monitoring to understand the emergence and spread of Usutu virus in the Netherlands, 2016–2018

Munnink

Munger

Nieuwenhuijse

et al. 2020

Sci Rep

View full text Add to dashboard Cite

Usutu virus (USUV) is a mosquito-borne flavivirus circulating in Western Europe that causes die-offs of mainly common blackbirds (Turdus merula).In the Netherlands, USUV was first detected in 2016, when it was identified as the likely cause of an outbreak in birds. In this study, dead blackbirds were collected, screened for the presence of USUV and submitted to nanopore-based sequencing. Genomic sequences of 112 USUV were obtained and phylogenetic analysis showed that most viruses identified belonged to the USUV Africa 3 lineage, and molecular clock analysis evaluated their most recent common ancestor to 10 to 4 years before first detection of USUV in the Netherlands. USUV Europe 3 lineage, commonly found in Germany, was less frequently detected. this analyses further suggest some extent of circulation of USUV between the netherlands, Germany and Belgium, as well as likely overwintering of USUV in the netherlands.Usutu virus (USUV) is a mosquito-borne arbovirus of the genus Flavivirus. The virus has a positive-stranded RNA genome with a genome length of around 11,000 nucleotides which encodes a single polyprotein. The polyprotein is processed by viral and host proteases into structural and non-structural proteins 1 . The life cycle of USUV involves mosquitoes (mainly Culex sp. 2,3 ) as vectors and wild birds as the main amplifying hosts. Humans and other mammals can be infected by mosquito bites and are generally considered dead-end hosts. Recent studies revealed that USUV can also be detected in small mammals such as bats 4 , rodents and shrews 5 .USUV was first identified from a Culex neavei mosquito in South Africa in 1959 6 . Over subsequent decades, it was sporadically reported in several mosquito and bird species, and twice in a human patient with fever and rash in African countries 7 . USUV was for first identified in Europe in 2001, when it was determined to be the causative agent of a mass mortality event in several bird species in Austria 8 . This prompted retrospective analysis of archived tissue samples from dead wild birds in Italy in 1996, which revealed an earlier presence of the virus in Europe 9 . Our understanding of the USUV geographical range has since expanded to include the majority of European countries 10 , where outbreaks are marked by mass die-offs of wild birds, with the heaviest toll on common blackbird (Turdus merula) populations. In Germany, it has been demonstrated that five years after the first detection of USUV in the southwest of the country, circulation of the virus was associated with a 15.7% decline in the common blackbird population in USUV-suitable areas 11 .The recent emergence of USUV epizootics among wild bird populations in Europe has been accompanied by reports of USUV infections in humans. Pathogenicity in humans appears to range from asymptomatic or mild symptoms, as shown in seroprevalence studies among healthy blood donors in Italy 12 , Germany 13 , Austria 14 and the Netherlands 15 to neuroinvasive infections associated with encephalitis or meningo-encephalitis, m...

show abstract

Section: Methodsmentioning

confidence: 99%

Genomic monitoring to understand the emergence and spread of Usutu virus in the Netherlands, 2016–2018

Munnink

Munger

Nieuwenhuijse

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…For the lineage-specific assays, 727bp fragments of the Egene were amplified with the primers WNV E-F (5´-CAACTGCCTAGGAATGAGYAACAG-3´) and WNV E-R (5´-GGCATGAGGTTCTTCAAACTC CA-3´). The obtained PCR products were ligated into pCRII (3'UTR) and pCR2.1 (E-gene) (Life Technologies, GmbH, Darmstadt) and used for in vitro transcription of an RNA standard with T7 RNA-polymerase (Roche, Mannheim, Germany) as described previously (Nikolay et al, 2014).…”

Section: Rna Standardmentioning

confidence: 99%

Real-Time RT-PCR Assays for Detection and Genotyping of West Nile Virus Lineages Circulating in Africa

Fall

Faye

Weidmann

et al. 2016

Vector-Borne and Zoonotic Diseases

View full text Add to dashboard Cite

“…99 The assay can be used in human blood and CSF samples, and showed a sensitivity of 50 genomic copies per reaction (corresponding to 2,200 copies/mL) and 1 plaque forming units (PFU)/mL of USUV isolate. Later on, a similar assay based on sequences from Europe and Africa, 115 and a one-step real-time multiplex RT-PCR, which efficiently detects and differentiates in a single reaction WNV strains from lineages 1 and 2 and USUV, have been reported. 116 More recently, a NS1-antigen protein microarray for the serologic differential diagnosis of flavivirus infections in horses, including USUV, has been developed and validated.…”

Section: Diagnosismentioning

confidence: 99%

Usutu virus: current knowledge and future perspectives

Saiz¹,

Blázquez²

2017

VAAT

View full text Add to dashboard Cite

Abstract:The Flavivirus genus (Flaviviridae family) contains important pathogens such as yellow fever virus, Japanese encephalitis virus, St Louis encephalitis virus, West Nile virus, Usutu virus (USUV), Zika virus, and dengue virus, many of which constitute a worrisome threat to global human and animal health. USUV is transmitted by mosquitoes and, as any other flavivirus, is an enveloped plus-strand RNA virus. The virus was first isolated from Culex neavei mosquitoes in South Africa in 1959 near the Usutu River, from where it takes its name. Since then, the virus was confined to Africa until its first detection in Austria in 2001, although it was probably present in Europe since 1996 or even earlier. After that, USUV has spread throughout Europe, causing a considerable mortality among birds and a few neurologic cases in humans. The main USUV natural hosts are birds, but infection has also been reported in other vertebrate species, including humans. The fast spread of the virus through the continent, the relatively high mortality caused in birds, and the recent neuroinvasive human cases related to USUV infection reported in Europe have raised serious concerns about its possible consequences for public health. Here, an updated review of current knowledge about this emerging pathogen is presented. Keywords: Usutu virus, flavivirus, host cell-virus interactions, surveillance, prophylaxis Biology of the virus Molecular classification and phylogenyUsutu virus (USUV) is a member of the Flavivirus genus within the Flaviviridae family ( Figure 1A). In 2004, the complete genomic sequences of two USUV strains, one African (South Africa-1959) and one European (Vienna-2001), were used to build a phylogenetic tree. These two strains showed a 97% and 99% homology at the nucleotide (nt) and amino acid (aa) level, respectively.1 Both strains were closely related to Murray valley encephalitis virus (73% and 82% nt and aa similarity), Japanese encephalitis virus (71% and 81% nt and aa similarity), and to West Nile virus (WNV; 68% and 75% nt and aa similarity). Nowadays, dozens of complete sequences are available in the data banks. In a recent study, the sequence identity among seven USUV strains was 96%-99% and 99% at the nt and aa levels, respectively.2 The only exception was a 1969 isolate from Central African Republic (CAR-1969) that presented homologies of 81% and 94% at the nt and aa levels with other African sequences ( Figure 1B). Due to these differences, it has been suggested that CAR-1969 formed an USUV subtype strain.3 A comparison with the original South African SAAR-1776 strain showed that the mutations found among different European and African strains were scattered throughout the genome, with some unique substitutions and some that were present

show abstract

Development of a Usutu virus specific real-time reverse transcription PCR assay based on sequenced strains from Africa and Europe

Cited by 56 publications

References 8 publications

Genomic monitoring to understand the emergence and spread of Usutu virus in the Netherlands, 2016–2018

Genomic monitoring to understand the emergence and spread of Usutu virus in the Netherlands, 2016–2018

Real-Time RT-PCR Assays for Detection and Genotyping of West Nile Virus Lineages Circulating in Africa

Usutu virus: current knowledge and future perspectives

Contact Info

Product

Resources

About