Two COVID-19 cases of the Omicron variant have been detected in Karnataka - in men aged 46 and 66 - the Health Ministry said Thursday, calling for calm amid growing concern over a strain that has triggered global alarm. The 66-year-old man, who has received both vaccine doses, travelled from South Africa on November 20 with a negative Covid report. He tested positive on arrival and was asymptomatic, following which he was told to self-isolate. A week later (with a negative Covid report from a private lab) he flew to Dubai. Samples from 24 primary and 240 secondary contacts have returned negative test results.