Wednesday 5 January 2022 07:16, UK
Increasing numbers of countries around the globe are reporting cases of the Omicron variant.
Since it was first reported by scientists in South Africa in November, the COVID-19 strain has spread internationally and is now known to be in at least a third of countries.
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But the genetic sequencing of the virus that confirms a case as Omicron doesn’t take place everywhere, so it may be much more widely spread than is already known.
The series of maps below shows which countries have been sequencing enough case samples to be able to trace how dominant Omicron has become.
Patient zero, called “n=1” or the “index case” by the scientific community, arrived at Hong Kong International Airport on 11 November, having flown in from South Africa via Doha in Qatar on flight QR818.
He was one of a handful of early cases that emerged in the southern part of the continent, which saw South African health authorities tell the world a new variant had been discovered.
South African scientists identified the variant in case samples as far back as the start of November.
Botswana was another early hotspot, but according to researchers in Nigeria, it appears as if the variant may have been circulating widely earlier than that, as re-examined cases in that West African country show signs of the variant from 18 October.
By the middle of November, scientists are now certain that Omicron was present in France, India, and Canada.
On 24 November, South African scientists went public, and it began to be picked up elsewhere – in Israel, Malawi, Belgium, Germany, Italy and the Czech Republic.
More and more European countries began to report their first cases, before it turned up in Australia and the US.
As it spread, countries across the planet reacted by closing their borders or reintroducing severe travel restrictions.
Meanwhile, Omicron rates surged in South Africa, with the variant becoming responsible for more than nine out of 10 cases by early December.
A dual epidemic of Delta and Omicron was first signalled by the UK’s chief medical officer, Professor Chris Whitty, as cases began to surge in the four home nations.
Omicron is thought to have been in Britain since mid-November, and by the middle of December it was already accounting for more than nine out of 10 cases.
In doing so, it was out-competing the Delta variant (first detected in India earlier in 2021), which had itself replaced the Alpha variant (first detected in Kent in late 2020).
As Omicron was emerging, Delta was wreaking havoc in multiple countries around the planet, leading to what World Health Organization (WHO) chief Tedros Adhanom Ghebreyesus later called a tsunami of cases heading our way.
In the last week or so, surging rates of Omicron have been reported in Russia, Romania, India, and Australia.
In the process, just as in the UK, authorities have been grappling with the risk that large numbers of essential workers will be unable to carry out their jobs, either through sickness, or because they have to self-isolate.
One of the few countries yet to see a significant uptick in Omicron is China, which has a zero COVID policy involving severe restrictions to keep the virus in check.
Officials say their recent outbreaks – which include one that has locked down the 12 million population megacity of Xian since 23 December – are driven by the Delta variant, but the Winter Olympics in a few weeks may change things.
Back to where it seemingly all began, if Omicron cases in South Africa have indeed peaked and are going down, it may be too early to tell.
WHO official Dr Abdi Mahamud said on Tuesday the country’s case rates may be an outlier, and should not be used to provide expectations of Omicron infections going forward.
He said it was instead necessary to build projections based on what has happened in UK and US cities like London and New York to see what might happen around the world.