Where Did Omicron Come From? And Why Did It Evolve?

The question of “Where did Omicron come from?” weighs a lot on people’s minds — especially since we know very little about this new COVID-19 variant. Knowing the answer to this question can help us unravel the Omicron dilemma, and hopefully figure out how to keep the variant from spreading.

Where Did Omicron Come From?

The Omicron variant was first discovered in South Africa, where a team of researchers announced the new variant of interest. But what exactly does a variant of interest mean?

Variants are actually normal, and scientists expect viruses to evolve after some time. But for the most part, the changes or mutations that happen in a virus are not significant. This means that while a variant is genetically distinct from the original, it doesn’t necessarily mean that it’s more virulent, infectious, or resistant to vaccines. Most variants aren’t considered variants of interest.

However, in variants of interest, the changes are significant enough to warrant attention. This could mean that the virus can cause more serious infections, spread more easily, or it can better resist the protection that current vaccines provide. The last one is evident in the flu virus, wherein the vaccine changes year after year to adapt to new mutations.

One interesting thing about Omicron is that the closest strains to it were ones from mid-2020. In most variants, researchers can trace the evolution of the strain continuously over time. This is why the Omicron variant is surprising, since it seemingly came out of nowhere.

Now, to answer the question “Where did Omicron come from?” researchers have a number of theories:

1. It May Have Come from Animals

The first theory is that it could have evolved from an infected animal. COVID-19 can also infect animals, and a sick animal could potentially infect a human. However, this theory is highly unlikely as the genome of Omicron doesn’t show any genetic information from animals. So it’s more likely that it evolved in a human.

2. It Could Have Evolved Under the Radar

The second possibility is that the variant evolved in a population that wasn’t being monitored. What could have happened is that it developed in an isolated community where vaccination rates are low.

The problem with this theory is that a lot of genetic sequencing is happening in South Africa. It’s highly unlikely that this variant would go undetected for such a long time. Andrew Rambaut of the University of Edinburgh shares that, “I’m not sure there’s really anywhere in the world that is isolated enough for this sort of virus to transmit for that length of time without it emerging in various places.”

3. It Could Have Evolved in an Immunocompromised Person

The last, and most likely possibility is that it evolved in an immunocompromised person. The theory is that the virus might have remained and evolved in the body of a person with a weak immune system, such as someone with HIV. What could have happened is that the virus lingered inside the person’s body for an extended period of time. This is possible if the immune system is not strong enough to completely eradicate the infection.

Over time, the virus replicated and evolved, and when an opportunity came, it infected someone else and it started to spread from there.

This had already happened before in a woman with untreated HIV who was infected with COVID-19. There are also millions of people in South Africa with untreated HIV, so this is the most likely scenario.

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