The Omicron coronavirus variant detected in southern Africa could be the most likely candidate to displace the highly contagious Delta variant. That’s according to Adrian Puren, the Acting Executive Director of South Africa's National Institute for Communicable Diseases - or NICD. He spoke to Reuters on Tuesday. "We thought what will outcompete Delta? That has always been the question, what would outcompete Delta in terms of transmissibility at least." The discovery of Omicron has caused global alarm, with countries limiting travel from southern Africa for fear it could spread quickly even in vaccinated populations and the World Health Organization saying it carries a high risk of infection. If Omicron proves even more transmissible than the Delta variant, it could lead to a sharp spike in infections that could put pressure on hospitals. Puren said scientists should know within four weeks to what extent Omicron can evade the immunity generated by vaccines or prior infection, and whether it leads to worse clinical symptoms than other variants. Anecdotal accounts by doctors who have treated South African COVID-19 patients say Omicron appears to be producing mild symptoms, including a dry cough, fever and night sweats, but experts have cautioned against drawing firm conclusions. Puren said it was too early to say whether Omicron was displacing Delta in South Africa.. Anne von Gottberg, a clinical microbiologist at the NICD, said it looked like infections were rising throughout the country… But cautioned against linking that with Omicron just yet:"In fact some of those admissions might have started before the emergence of Omicron. We are also seeing that there was an increase in influenza cases in South Africa just in the last month or so, and so we need to be really careful to look at the other respiratory infections..." Leaders in southern Africa have criticized swift travel restrictions by the United States and other nations as unfair and crippling to their tourism and other sectors. South Africa has reported close to 3 million COVID-19 infections during the pandemic and over 89,000 deaths, the most on the African continent.