COVID-19: Is Omicron a serious worry or an evolutionary dead end?
So the new variant has a name, but we’ve no idea about its reputation.
On paper at least the Omicron variant looks terrifying. It has more mutations than any previously observed strain of COVID.
And the mutations aren’t just a random jumble of genetic changes. A worrying number of them are in parts of the virus we know are important for becoming more infectious as well as avoiding antibodies and other parts of the immune system.
Take the receptor-binding domain, a key part of the virus’ spike protein that allows it to grab onto our cells. The Delta variant has two mutations in the RBD, the now rare Beta variant (formerly known as the South Africa variant) has three.
Omicron has 10. If there was a menu of possible mutations suited to the human host, Omicron ordered the full English.
This is what made scientists sit up and take notice when their colleagues in South Africa first published the sequence of the new variant.
But what caused today’s international response was evidence that a recent and steep spike in cases in south African cases may be due to Omicron. Its powers may not just be theoretical.
But we’re probably weeks away from knowing whether Omicron is a serious worry or another of COVID’s many evolutionary dead-ends.
First, its role in the recent spike in cases in South Africa isn’t confirmed. It certainly makes up the majority of cases in the COVID surge in Gauteng province (the area surrounding Johannesburg and Pretoria), and there’s evidence it’s on the rise elsewhere in South Africa.
But cases are very low in the country – around 70 times lower than the daily average in the UK. Even a small increase in numbers of a new variant can look alarming when numbers are low.
Then there’s the fact the short natural history of COVID-19 has taught us that appearances can be deceptive.
The Beta variant is a case in point. It was effective at evading antibodies from vaccines, it caused a significant wave of infection in South Africa but it never gained a foothold against the more infectious Delta variant.
When Delta spread to South Africa it rapidly displaced Beta.
Having lots of mutations, so the theory goes, could incur costs to the virus in some other part of its biology, making it less fit in a slightly different environment to the one it evolved in.
What scientists in South Africa are doing now is growing the Omicron strain in the laboratory so they can start to test it against antibodies from vaccinated or previously infected people.
They’re also planning to share samples with their colleagues abroad including teams in the UK.
These experiments should confirm whether Omicron truly is more contagious, or can avoid vaccines and hold its own against the delta strain.
But that will take weeks of work. Until then, eyes will be on South Africa’s outbreak to see whether it provides more answers: is this just a first, but short-lived, flush from a flashy but flawed viral mutant? Or are we witnessing COVID’s next big evolutionary step?
(c) Sky News 2021: COVID-19: Is Omicron a serious worry or an evolutionary dead end?