With the Omicron variant of SARS-CoV-2 continuing to run rampant, Italian in vitro diagnostics (IVD) company A.Menarini Diagnostics has unveiled a new real-time (RT)-PCR-based test that can detect several variants of the coronavirus including Omicron and Delta.
The CE certified PCR test kit is called CoronaMeltVAR and detects viral RNA in nasopharyngeal, oropharyngeal and saliva swab samples and produces results in less than two hours.
The CE-IVD CoronaMeltVAR test is based on intercalating dye and melting curve analysis. Menarini Diagnostics says the kit detects positive samples with high sensitivity by amplifying two targets that are both compatible with all of the variants as well as the wildtype (WT) or original version of the virus.
“We are extremely proud to have made this unique solution available so quickly. It is helping healthcare professionals in providing a specific, rapid and accurate solution for the diagnosis and identification of Covid-19 Omicron variant,” said Fabio Piazzalunga, Menarini Silicon Biosystems chairman and CEO, and Menarini Diagnostics general manager and global head in a news release from the company.
A.Menarini Diagnostics is a division of the Menarini Pharmaceutical Group.
The test generates distinct signals for the presence of the Omicron BA.1 sublineage, which is the original and dominant version of the variant. The test also detects its sister sublineage BA.2, also dubbed the “Stealth Omicron” as it has mutations in the Spike (S) protein that do not cause the S gene target failure (SGTF) or “dropout” characteristic of BA.1 and the Alpha variant. The test can also identify the Alpha, Beta/Gamma and WT/Delta lineages.
Each sample only requires a single run to generate responses and because there is no loss of sensitivity as with normal kits, the need to perform a second reflex test on positive samples is eliminated.
Menarini Diagnostics’ test kit is compatible with most RNA extraction protocols and RT-PCR instruments that can perform melting curve analysis at moderate resolution.
Most of the current PCR test kits can detect the Omicron variant. However, there is continuing conversation and research into what the best sampling site is. There are some scientists who say that Omicron can be transmitted when it has just infected the throat and saliva but not the nose, which means tests may not pick up the virus in nasal swab samples. Reuters reported that a recent US study showed that PCR tests using saliva samples could detect the virus on average three days before samples from the nose showed positivity on antigen tests. As a result, some experts are suggesting that people take samples from both the throat and nose. The UK has approved rapid antigen tests that involve swabbing both the throat and nose or only the nose.
Overall, testing capacities have been compromised amid the rapid spread of Omicron, with test supplies unable to keep pace with the sheer number of COVID-19 cases. This has led to drops in testing and in some places like Canada, PCR testing is only recommended for eligible groups of people who meet certain criteria. This has significant implications in settings like schools where teachers and parents have been relying on regular testing as a safeguard against COVID. Due to test shortages, prices for both PCR and antigen tests have been going up drastically.
Last week, the White House announced that 5 million rapid tests and 5 million PCR tests would be made available to schools beginning this month to alleviate supply shortages and help guide the safe reopening of schools. Additionally, the US government also began offering free rapid antigen tests to the public on Tuesday via a new website it launched for the purpose.