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Introduction EV-D68 is likely under-reported because an enterovirus PCR is usually not run for patients with respiratory symptoms; moreover 73% of rhinovirus (HRV) assays detect EV-D68, misleading clinicians as to the causative virus. Aims Technical validation of an EV-D68 PCR. Determine whether a one-step PCR is sufficient or whether a two-step PCR is required for detection of the virus in respiratory tract samples. Determine whether any samples that tested HRV positive in our hospital between July 2018- January 2019 were in fact EV-D68 positive. Methods and Results Primers and probes selected according to those already validated in Poelmana et al and tested in 1 step PCR with negative and positive control: successful. Sensitivity tested against NGS sequenced EV-D68 positive samples from our own laboratory, 5 from another teaching hospital and 2 QCMD samples: 1 and 2 step PCR sensitive, including 2-step PCR with internal control. Specificity successfully tested against many non- EV-68 samples positive for other viruses and bacteria. Comparison of Cq values of 1 step PCR versus 2 step PCR with internal control. Cq values 2-step PCR 1:400 dilution. Epidemiological study retrospectively testing all 104 HRV positive respiratory samples and DNA isolates from last week July 2018 to second week January 2019 with 2-step PCR. There were 8 positive cases, clustered in November and December. In only one of the 8 cases was EV-D68 detected in an adult patient, who was immunocompromised and not seriously ill. In the remaining cases, all children, none of the patients experienced concomitant central nervous system symptoms. Five cases required PICU admission, one had underlying asthma. Conclusion A 2-step EV-D68 RT PCR should be available as an add on diagnostic test for children with acute respiratory symptoms, in particular for paediatric ICU patients. |
