Adam Herridge, Product Manager at Primerdesign, talks to rapidmicrobiology.com about how his team responded to the growing novel coronavirus epidemic and delivered the genesig 2019-nCoV qPCR Kit in rapid time. It was the first diagnostics kit to be made in Europe with 100% specificity, it is exceptional value for money and is advantageous to low-resource and field-use scenarios.

Q: Primerdesign have brought this kit to market quickly – is it record time? When did you start working on it?
A: Primerdesign was the first European Medical Diagnostics company to produce a commercially available molecular detection kit specifically for 2019-nCoV.  Development of the kit started as soon as it was apparent that the virus was spreading and becoming a global health threat; the team managed to develop and optimise a kit within two weeks.

Q: What technology does the kit use and what specimens are suitable?
A: The genesig 2019-nCoV uses qPCR (quantitative polymerase chain reaction) through Taqman-style probe cleavage to generate a fluorescent signal in the presence of and detection for this novel Coronavirus strain.  Any high-quality nucleic acid extraction is a suitable sample for the test.  In this instance, samplers are typically using a nasopharyngeal swab

Q: What other instrumentation/equipment is needed?
A: A nucleic acid extraction kit is needed first to prepare the patient sample.  This can be a manual or automated process, which involves lysis and purification of the sample, to be ready for testing.  Once extraction is complete, the sample, along with our reagents, are loaded on to a qPCR instrument, which amplifies the nucleic acids and interprets the data to provide a result to the user

Q: What sort of lab/applications is it intended for?
A: The kit is designed so that any molecular lab with the ability to perform qPCR can use our assay.  Our reagents, including master mix, come lyophilised.  This means shipping and storage at ambient temperature are possible. This allows transportation to tropical climates and eliminates the need for refrigeration. This gives the added advantage of enabling testing to be performed in field laboratories and other low resource settings, which otherwise, may not have been possible. Once the sample is ready for testing, the user will use a qPCR instrument

Q: How can labs be confident in the results?
A: With our Advanced format kit, the user is provided with a positive control, an internal extraction control, an endogenous control and pure H₂O.  The positive control is used to show that a successful PCR has occurred, and for quantification of a sample.  An internal extraction control is used in the sample setup and qPCR, which then allows an individual to be confident of a high-quality extraction.  The endogenous control is used to show the presence of sufficient and appropriate sample input (e.g. the swab had the correct amount of sample on it).  And the pure H₂O is used to provide a sure negative sample, so an individual can be assured their positives are true positives.

Q: How does this kit compare to others that have also recently appeared?
A: The Primerdesign 2019n-CoV kit has been designed specifically for the Wuhan specific strain, not associated strains.  It shows 100% homology with the genomes of this strain that have been sequenced to date in the public domain.  This includes global strains, as well as China.  We have undertaken extensive bioinformatic analysis to confirm inclusivity and exclusivity parameters which have shown the Primerdesign kit to be more specific than alternative kits.  For example, the WHO designed their published assay prior to knowing the 2019-nCoV sequence and as such, that assay detects other coronaviruses such as SARS-related viruses.  We believe that our kit will have improved specificity over the Chinese CDC and US CDC designs as we have designed our detection profile to have a greater number of mismatches with related species. This means Primerdesign's kit will not detect other species, whereas other assays available will, and therefore have reduced specificity. 

Q: What will happen should the virus continue to mutate?
A: Viruses inherently have a high mutation rate.  Should the targeted region of the virus mutate, the specificity of the assay may be reduced, which would be the same for any competitor kit or PCR assay.  To combat this, as the sequence data is collected from newly 2019-nCoV infected patients from around the world and then published, our in-house bioinformatics team reviews this daily to check our detection assay has homology with all of these published sequences, and can still detect all positive 2019-nCoV samples.