First external quality assessment of molecular and serological detection of rift valley fever in the western Mediterranean region

Pas de clé UTRift Valley fever (RVF) is a mosquito-borne viral zoonosis which affects humans and a wide range of domestic and wild ruminants. The large spread of RVF in Africa and its potential to emerge beyond its geographic range requires the development of surveillance strategies to promptly detect the disease outbreaks in order to implement efficient control measures, which could prevent the widespread of the virus to humans. The Animal Health Mediterranean Network (REMESA) linking some Northern African countries as Algeria, Egypt, Libya,Mauritania, Morocco, Tunisia with Southern European ones as France, Italy, Portugal and Spain aims at improving the animal health in the Western Mediterranean Region since 2009. In this context, a first assessment of the diagnostic capacities of the laboratories involved in the RVF surveillance was performed. The first proficiency testing (external quality assessment— EQA) for the detection of the viral genome and antibodies of RVF virus (RVFV) was carried out from October 2013 to February 2014. Ten laboratories participated from 6 different countries (4 from North Africa and 2 from Europe). Six laboratories participated in the ring trial for both viral RNA and antibodies detection methods, while four laboratories participated exclusively in the antibodies detection ring trial. For the EQA targeting the viral RNA detection methods 5 out of 6 laboratories reported 100% of correct results. One laboratory misidentified 2 positive samples as negative and 3 positive samples as doubtful indicating a need for corrective actions. For the EQA targeting IgG and IgM antibodies methods 9 out of the 10 laboratories reported 100% of correct results, whilst one laboratory reported all correct results except one false-positive. These two ring trials provide evidence that most of the participating laboratories are capable to detect RVF antibodies and viral RNA thus recognizing RVF infection in affected ruminants with the diagnostic methods currently available

Unexpected Rift Valley Fever Outbreak, Northern Mauritania

During September–October 2010, an unprecedented outbreak of Rift Valley fever was reported in the northern Sahelian region of Mauritania after exceptionally heavy rainfall. Camels probably played a central role in the local amplification of the virus. We describe the main clinical signs (hemorrhagic fever, icterus, and nervous symptoms) observed during the outbreak

ETUDE DE L'ACIDE OKADAIQUE, UNE PHYCOTOXINE MARINE DEVELOPPEMENT DE TECHNIQUES ANALYTIQUES ET EVALUATION DU POTENTIEL GENOTOXIQUE

PARIS7-Bibliothèque centrale (751132105) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

EQA for RVFV virus genome detection, RNA extraction and RT PCR instruments and methods.

<p>na = not available information</p><p>* Laboratory providing multiple datasets</p><p>**Friedrich-Loeffler-Institut (in-house) using primer sequences published by Bird et al. (2007)</p><p>EQA for RVFV virus genome detection, RNA extraction and RT PCR instruments and methods.</p

Results of the EQA for RVF IgM antibodies detection.

<p>Wild rum: wild ruminants (<i>Antidorcasmarsupialis</i>). Pos: RVF seropositive status; Neg: RVF seronegative status. + /—: samples identified as positive or negative by the participants. FP: false positive</p><p>^<i>†</i>IDvet: ID. Screen RVF IgM Capture</p><p>^<i>§</i><i>In-house assay</i>: test based on crude cell lysate as antigen</p><p>* Laboratory providing multiple datasets</p><p>Results of the EQA for RVF IgM antibodies detection.</p

Distribution of the correct results of laboratories participating to the EQAs for RVF antibodies detection (IgG and IgM).

<p>Group 1 includes laboratories, which correctly classified 15 out of the 15 tested samples, Group 2 represents the laboratory failing to one test result. For IgG EQA group 1 includes the laboratories: #1, #2, #3, #4, #5, #6, #7a, #8, #9, #9a, #9b, #10, while in group 2 #7. For IgM EQA group 1 includes #1, #2, #4, #5, #6, #7, #7a, #8, #9, #9a, #9b, #10 and group 2 #3.</p

Results of the EQA for RVFV virus genome detection, cycle threshold (Ct) values.

<p>Neg: RVFV seronegative bovine serum. No Ct: result above the threshold.</p><p>* Laboratory providing multiple datasets</p><p>Results of the EQA for RVFV virus genome detection, cycle threshold (Ct) values.</p

Distribution of the correct results of laboratories participating to EQA for RVFV genome detection.

<p>Group 1 represents laboratories which correctly classified 15 out of the 15 tested samples (#1a, #7, #8, #9, #10). Group 2 represents the laboratory failing to one test result (#1). Group 3 represents the laboratory, which misidentified 5 test results (#2).</p

Results of the EQA for RVFV virus genome detection.

<p>Neg: RVFV seronegative bovine serum. + / -: samples identified as positive or negative by the participants. FP: false positive result. FN: false negative result. Inc: Inconclusive results.</p><p>* Laboratory providing multiple datasets</p><p>Results of the EQA for RVFV virus genome detection.</p