Dec 7, 2012 (CIDRAP News) – Diagnostic tests for the novel coronavirus (CoV) that recently emerged in the Middle East are being deployed rapidly in Europe, and about 250 patients have already been tested for the virus, according to the European Centre for Disease Prevention and Control (ECDC).
An ECDC survey revealed that a screening test for the virus is available in 23 of 46 responding countries in the World Health Organization's (WHO's) European Region, according to a report yesterday in Eurosurveillance. Those include 19 of 30 countries in the European Union (EU) and the European Economic Area (EEA).
Confirmatory testing of positive screened samples is available in 22 of 46 responding countries, including 18 of 30 EU and EEA countries, according to the survey. Six EU and EEA countries reported that they had tested about 250 patients who met the WHO surveillance criteria, the ECDC said.
The available screening test was the upE RT-PCR (reverse-transcriptase polymerase chain reaction) assay, while confirmatory testing involved ORF1b RT-PCR or other target RT-PCR assays with sequence analysis, the report said.
Nine novel CoV infections, with five deaths, have been identified in the world so far.
In a companion report, a German team describes a new confirmatory test for the novel CoV and a serologic test to detect antibodies to the virus. The authors say the recent investigation of a cluster of novel CoV cases in Saudi Arabia suggested that RT-PCR testing may miss cases in patients with symptoms and epidemiologic links to known cases.
The team used samples from a patient who was treated in Germany to develop their tests. (The WHO reported on Nov 23 that a Qatari man had been flown to Germany for treatment and recovered there.) The new confirmatory test is described as a "rigorously validated and highly sensitive" real-time RT-PCR assay targeting the ORF1a gene, called the 1A assay, which can be used in combination with the previously reported upE assay.
The authors describe their serologic test as a biologically safe immunoflorescence assay, but they note that it is unknown to what extent novel CoV antibodies cross-react with those against common human coronaviruses such as OC43 and HKU1.
They suggest that the serologic test might be used for confirmatory testing of persons epidemiologically linked to novel CoV cases. In addition, the scientists describe two other new RT-PCR assays for sequencing, targeting the novel CoV RdRp gene and N gene.
Palm D, Pereyaslov D, Vaz J, et al. Laboratory capability for molecular detection and confirmation of novel coronavirus in Europe, November 2012. Euro Surveill 2012 Dec 6;17(49):pii=20335 [Full text]
Corman VM, Muller MA, Costabel U, et al. Assays for laboratory confirmation of novel human coronavirus (hCoV-EMC) infections. Euro Surveill 2012 Dec 6;17(49):pii=20334 [Full text]