Every time a new COVID-19 variant emerges, it sends us spiraling into uncertainty, driven by three main questions: Is it more contagious than previous variants? Will it cause more severe illness? And, crucially, how effective will our vaccines be against it? Historically, most variants have not posed serious threats. However, the alpha and delta variants showed mutations that increased transmissibility, severity of illness, and in delta’s case, a higher chance of vaccine evasion. The WHO has classified omicron as a “variant of concern,” indicating that the global risk is “very high.” This is epidemiology lingo for “We’re worried.”
But the situation is more complex than just panic among WHO scientists. Omicron is indeed concerning. Here’s what we currently understand.
It Has Numerous Mutations
To break it down: mRNA vaccines instruct our cells to create a spike protein similar to that of the COVID-19 virus. Our immune system then identifies this spike protein as foreign, producing antibodies to combat it. When we encounter an actual COVID-19 virus, our immune system recognizes the spike protein and reacts. Delta has 18 mutations on its spike protein, while omicron boasts an astonishing 34 mutations.
In general, more mutations raise alarm bells, particularly when they occur on the spike protein. This is critical because vaccines prepare our bodies to fight COVID based on its spike protein characteristics. If the spike protein mutates too significantly in key areas, known as the “receptor-binding domain,” our antibodies may fail to recognize it, rendering vaccines less effective. Omicron has several mutations in this crucial area, which could lead to more breakthrough infections among vaccinated or previously infected individuals. Some mutations also suggest enhanced transmissibility, and early data supports this.
“We’ve observed these mutations in other variants, typically in small groups, and they were slightly harder to neutralize but didn’t spread well,” said Dr. Kevin Miller, a virologist at a major university. “Now, all together? It’s a mystery.”
It Must Outcompete Delta
For omicron to truly pose a significant risk, it needs to be more contagious than delta. Unfortunately, experts believe it “appears to be more transmissible than delta, even among vaccinated individuals.” They anticipate that vaccines will be less effective against omicron, resulting in an increase in breakthrough infections, whether symptomatic or not. The CEO of Moderna, Alex Turner, caused a stir in the financial markets when he indicated that current vaccines might not perform as well against omicron. He mentioned that there could be “a material drop” in efficacy against this variant. “I can’t predict how much, as we need to wait for data,” he added. “But all the scientists I’ve consulted agree that this isn’t promising.”
Omicron is currently surpassing delta in terms of transmissibility, and vaccines appear to be less effective against it. However, we may have to wait about two weeks for more comprehensive data on vaccine efficacy against omicron.
Some Positive Aspects of Omicron
In line with the fundamental rule of epidemiology—listen when virologists express concern—researchers are diligently sequencing, tracking, and investigating omicron. We should know more in the upcoming weeks regarding its spread, transmission rates, breakthrough infection rates, and the severity of infections among both vaccinated and unvaccinated individuals.
Historically, viruses that kill their hosts too quickly struggle to spread effectively. Preliminary observations suggest that omicron does not lead to more severe illness compared to other variants. Dr. Maya Patel, a virologist in South Africa where omicron was first identified, noted that cases there have mostly been “mild or moderate… That’s encouraging. But let’s remember it’s still early.” Severe omicron cases are primarily among those who are not fully vaccinated, according to Dr. Rudo Mathivha, head of an intensive care unit in Soweto. Dr. Elena Cohen from Israel also reported that vaccinated individuals seemed to experience only mild symptoms from omicron. Additionally, The New York Times’ Carl Robinson confirmed that, “For now, there’s no evidence that omicron causes more severe illness than earlier variants.”
While concerns about vaccine effectiveness persist, Dr. Hannah Lee, an epidemiologist at a leading university, reassured us via social media: “Omicron resembles the song ‘One Piece at a Time’ by Johnny Cash, where various successful mutations from past variants come together. It looks odd, but we’re not entirely sure what it means.” So, while there is a solid hypothesis that omicron will be more contagious and evade immune responses more effectively, it doesn’t appear to cause higher rates of severe illness and death than previous variants.
In summary, vaccinated individuals may face a higher likelihood of infection, and the virus may spread more easily. However, COVID vaccines were designed primarily to prevent severe illness and death, not to eliminate infections entirely. Omicron could surpass delta, infect more vaccinated individuals, and its rapid transmission among unvaccinated populations could pose significant risks to those without access to vaccines. This situation should urge countries like the US to distribute vaccines to regions in dire need.
Virologists may be on high alert, but it’s too soon for us to panic until we know more about omicron’s transmissibility and its ability to evade our vaccines.
Summary
The Omicron variant of COVID-19 has raised significant concerns due to its extensive mutations, particularly on the spike protein, which may allow it to evade vaccine-induced immunity. It appears to be more transmissible than the delta variant, leading to predictions of increased breakthrough infections among vaccinated individuals. However, early reports suggest that omicron does not cause more severe illness than other variants. Ongoing research will help clarify its impact and inform public health responses.