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- Hayes, A., et al.
(författare)
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A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts
- 2020
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 92:8, s. 1065-1074
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Tidskriftsartikel (refereegranskat)abstract
- Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10−5). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.
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- Hodcroft, EB, et al.
(författare)
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Evolution, geographic spreading, and demographic distribution of Enterovirus D68
- 2022
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Ingår i: PLoS pathogens. - : Public Library of Science (PLoS). - 1553-7374. ; 18:5, s. e1010515-
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Tidskriftsartikel (refereegranskat)abstract
- Worldwide outbreaks of enterovirus D68 (EV-D68) in 2014 and 2016 have caused serious respiratory and neurological disease. We collected samples from several European countries during the 2018 outbreak and determined 53 near full-length genome (‘whole genome’) sequences. These sequences were combined with 718 whole genome and 1,987 VP1-gene publicly available sequences. In 2018, circulating strains clustered into multiple subgroups in the B3 and A2 subclades, with different phylogenetic origins. Clusters in subclade B3 emerged from strains circulating primarily in the US and Europe in 2016, though some had deeper roots linking to Asian strains, while clusters in A2 traced back to strains detected in East Asia in 2015-2016. In 2018, all sequences from the USA formed a distinct subgroup, containing only three non-US samples. Alongside the varied origins of seasonal strains, we found that diversification of these variants begins up to 18 months prior to the first diagnostic detection during a EV-D68 season. EV-D68 displays strong signs of continuous antigenic evolution and all 2018 A2 strains had novel patterns in the putative neutralizing epitopes in the BC- and DE-loops. The pattern in the BC-loop of the USA B3 subgroup had not been detected on that continent before. Patients with EV-D68 in subclade A2 were significantly older than patients with a B3 subclade virus. In contrast to other subclades, the age distribution of A2 is distinctly bimodal and was found primarily among children and in the elderly. We hypothesize that EV-D68’s rapid evolution of surface proteins, extensive diversity, and high rate of geographic mixing could be explained by substantial reinfection of adults. Better understanding of evolution and immunity across diverse viral pathogens, including EV-D68 and SARS-CoV-2, is critical to pandemic preparedness in the future.
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- Verbeeck, J., et al.
(författare)
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JC viral loads in patients with Crohn's disease treated with immunosuppression: can we screen for elevated risk of progressive multifocal leukoencephalopathy?
- 2008
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Ingår i: Gut. - : BMJ. - 1468-3288 .- 0017-5749. ; 57:10, s. 1393-1397
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Tidskriftsartikel (refereegranskat)abstract
- Background and aims: Anti-alpha 4 integrin therapy with natalizumab is efficacious in refractory Crohn's disease and in multiple sclerosis, but carries an estimated 1/1000 risk of progressive multifocal leukoencephalopathy (PML) caused by reactivation of latent JC virus infection. Athough anti-alpha 4 integrin therapies are likely to be introduced in the clinic, screening for the risk of PML has not been developed. Methods: We prospectively collected urine, serum, plasma and buffy coats from 125 patients with Crohn's disease, 100 control subjects with gastrointestinal (GI) disease, and 106 healthy volunteers. Four to eight weeks after this first sample collection, we additionally collected a set of urine, serum, plasma and buffy coat samples from the 125 patients with Crohn's disease, and a next set of samples was collected 12-16 weeks after the first collection. JC viral loads were determined with quantitative real-time polymerase chain reaction (PCR), and JC virus seroprevalence with a specific enzyme-linked immunosorbant assay ( ELISA). Results: The overall JC virus seroprevalence was 65%. JC virus DNA copies were detected in the urine from 29-44% of subjects, both those with Crohn's disease and controls. Median viral loads were significantly higher in patients with Crohn's disease who were immunosuppressed (7.36x10(6) copies/ml) compared to healthy volunteers (2.77x10(5) copies/ml) and compared to GI controls (1.8x10(6) copies/ml). Clearance at any time point occurred in 4/107 (3.7%) subjects only. JC viraemia was found in two patients with Crohn's disease. Conclusions: The natural history of JC virus in patients with Crohn's disease is still unknown. Our study results show that JC virus latency and urine viral shedding is frequent in immunosuppressed patients with Crohn's disease. More prospective studies are needed in order to agree on possible recommendations concerning the exclusion of patients with JCV viraemia from anti-alpha 4 integrin treatment.
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