Omicron in Australia: what does the new Covid variant mean, and how worried should we be?

We know the latest variant of concern' has arrived in the country, but we shouldn't assume the worst

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On Friday, a new Covid-19 variant first identified in southern Africa was revealed, and by Saturday, the World Health Organization (WHO) had named it Omicron and declared it a variant of concern". This is because it carries a high number of mutations on its spike protein linked with increased transmissibility, and which may decrease the effectiveness of measures such as vaccinations and treatments.

By Sunday, two Omicron cases were confirmed in Australia, where the government promptly slammed the border shut to travellers from nine African nations. So how worried should Australia be about Omicron, and when will we know more about it?