Participating in VER-IPT: is it worth the effort?

Abstract

Interlaboratory proficiency tests (IPTs) are an essential tool to maintain quality standards and performances of diagnostic laboratories at a high level. In 2022 the VER IPT reached its 4th edition. The panel consisted of 10 ampoules that contained all known genotypes of Betanodavirus, the causative agent of Viral Encephalopathy and Retinopathy. Detecting the presence or absence of the target in the samples by real time or conventional RT-PCR was the main target of the IPT. Species identification to be performed by sequencing or by any other method available at the participant’s laboratory was also encouraged. Twenty-four laboratories out of 25 participants completed the exercise on time. Thirteen out of 24 (54.16% of participants) obtained the maximum score, while the remaining 11 produced a percentage of correct results ranging between 70%-90%, achieving an overall good outcome. Notably, in this IPT edition the BFNNV (barfin flounder nervous necrosis virus) was included for the first time and did not pose any particular problems in its detection. Viral species identification gave results far below the expectations and only 50% of the participants completed this part of the exercise, scoring quite well; however, laboratories should make greater efforts in improving their capacity to correctly identify the genotype.