The TLDR: We revisit the dreaded new variant to assess where we are—and what we now know about it. For more background, check out our detailed explainer on Omicron—and variants, in general.
The latest numbers
Omicron has now been detected in 57 countries, but it is growing the fastest in South Africa and the UK.
South Africa: New cases are rising more quickly in SA than previous waves—and the R number is over 3. The reproduction number indicates how many people one person can infect. The country recorded a new high of 37,875 new cases on Sunday—a dramatic overnight surge from 17,154 the previous day. The latest and most prominent person to report contracting Covid: South African president Cyril Ramaphosa.
The UK: Cases caused by the variant are doubling every 2.2 days—and is outpacing the spread of South Africa, where it is doubling every three days. Some experts predict that Omicron cases will hit 64,000 a day in two weeks's time at the current rate in the UK. The government has raised the alert level to four—the highest being five. And a new study suggests that the country will see a new Omicron-fuelled wave in January—and anywhere between 20.9 million to 34.2 million cases between December and April, 2022.
India: has reported 38 Omicron cases. Maharashtra has the highest number—including a 1.5 year old toddler and three year old child. None of the cases appear serious.
Is it easier to detect?
Yes. The WHO recently recommended something called a ‘S-gene target failure’ test to detect the presence of Omicron—so we don’t have to wait for genome sequencing, which takes much longer. This is basically a version of the RT-PCR test—which looks at the RNA material in the virus. If this S-gene is missing, then it indicates the variant is Omicron.
A big ‘but’: As Scroll notes, only one company in the world makes the S-gene failure test recommended by the WHO. And it can manufacture 25 million test kits per week worldwide. So if Omicron spreads, this could turn into a bottleneck. Potential good news: the Indian Council of Medical Research just announced that it has developed its own test that can detect Omicron in two hours. But it has not been tested in the real world as yet.
Also, about those two Omicrons: Scientists have identified two sub-lineages of the variant BA.1 and BA.2. All this means is that BA.2 is missing some of the mutations of BA.1—and has ones that are different. The problem is that BA.2 doesn’t have the mutation which allows us to detect the variant using the S-gene failure test. Genome sequencing is required to spot it.
Is it more infectious?
Most likely, yes. The evidence is still preliminary but most experts point to the fact that Omicron has been able to outcompete Delta in South Africa—emerging as the dominant variant. Here’s what the data shows:
- A recent Japanese study found that Omicron is 4.2 times more transmissible than Delta. Omicron cases are doubling every two or three days—a much shorter time period compared to Delta.
- Also: British researchers found that Omicron is 3.2 times more likely to cause an infection within a household than Delta.
- Based on the rise in Covid cases and on sequencing data, experts estimate that Omicron can infect three to six times as many people as Delta, over the same time period.
Is it less severe?

|