The new Omicron coronavirus variant keeps spreading around the world, even as more countries try to seal themselves off by imposing travel restrictions.
First discovered in South Africa, the fast-spreading coronavirus variant is emerging in almost every corner of the world. So far, it has been detected in Britain, Germany, Italy, Belgium, Botswana, Israel and Hong Kong.
On Sunday, health officials in Australia confirmed that two travelers who arrived in Sydney from southern Africa tested positive for the new COVID-19 variant.
Another 12 passengers from southern Africa were also in 14 days of hotel quarantine, while around 260 other passengers and aircrew have been asked to isolate.
The discovery of Omicron, dubbed a "variant of concern" by the World Health Organization, has sparked worries around the world that it could resist vaccinations and prolong the nearly two-year Covid-19 pandemic.
Omicron is potentially more contagious than previous variants, but experts do not know yet if it will cause more or less severe Covid-19 compared to other strains.
The global alarm over the new variant has hit financial markets, with investors worrying it could stall a global recovery. Oil prices have tumbled by about $10 a barrel.
The Saudi index suffered its biggest single-day fall in nearly two years on Sunday which saw most Persian Gulf stock markets falling sharply.
Many countries have imposed or are planning restrictions on travel from southern Africa, with the South African government denouncing this as unfair and potentially harmful to its economy.
The United States, Brazil, Canada, European Union nations, Australia, Japan, South Korea and Thailand were the first countries to announce travel bans, but epidemiologists say such curbs may be too late to stop Omicron from circulating.
Much of Europe is already battling a surge in Covid-19 infections and some of them have reintroduced restrictions on social activity to try to stop the spread.
That is happening even as many developed countries are giving third-dose boosters, while less than 7% of people in low-income countries have received their first COVID-19 shot.