Three more international travellers have tested Covid-19 positive, following which their samples have been sent for genome sequencing and the ‘S’ gene test. Of the four travellers who have tested positive so far, the S-gene has been detected in the sample from one of the patients. Of the three new cases, three are males, two of them aged 21 and 25; both had returned from London, while the third one is 37 and had returned from Mauritius. He was staying in a hotel as he was supposed to travel to another country. “All the patients are asymptomatic and have been institutionally quarantined. Two were confirmed positive through contact tracing, while a third person had himself tested and turned out to be Covid-positive,” said an official.
Since the Omicron mutation is in the S-gene, a sample positive for this variant will have the S-gene missing. The World Health Organisation had suggested that countries using the PCR test containing the S-gene could utilise the S-gene target failure, an indicator for infection by Omicron subject to confirmation by genome sequencing.
“We are taking due care and the samples of all travellers are being sent for RT-PCR. We have found the S-gene in one of the samples, which means Omicron is not present. Meanwhile, the S-gene results of three samples are expected today (December 2). If the S-gene is missing, in that case, it will be presumed that the traveller may be infected (with Omicron),” said Additional Municipal Commissioner Suresh Kakani.