Everything that has been discovered about the omicron variant

The world has been watching with concern the advance of omicron for a month; the variant of the coronavirus that, according to data from the World Health Organization (WHO), in just a few weeks has expanded to a hundred countries and has shot number of covid-19 cases. But what do we know about the real risk of this variant? Is it more contagious? Does it cause a more serious illness? Do you avoid the defenses generated by vaccines and previous infections? None of these questions has, for now, a blunt answer. But the first studies suggest that this lineage is much more transmittable than its predecessors but, in turn, it seems to provoke less severe symptoms. The risk of omicron, experts point out, is not so much that it causes a more serious disease but that, due to the explosion of infections, the virus collapses the health system again.

This is that we know, for now, how omicron is changing the course of the covid-19 pandemic.

Is it more transmissible?

Everything points to yes. Epidemiological data confirm the suspicion that omicron is, indeed, more transmissible than its predecessors. According to the World Health Organization (WHO), in countries where there is community transmission of this variant, the number of covid-19 cases doubles every 1.5 and 3 days. Everything points, then, that in a matter of weeks this lineage could replace a delta variant that, since last summer, has been the predominant in practically the entire globe.

In South Africa, one of the first countries to detect this variant, omicron went from zero to representing 75% of the cases detected in just two weeks. In the United Kingdom, at the beginning of December it was estimated that the cases of this variant amounted to just 2% and by the middle of the month they were already over 80%. In United States, just a week ago omicron was 2.9% of the cases and now, according to the latest records, already exceeds 70% of detected infections.

Is it more severe or milder?

It seems not. Although, beware, the studies carried out to date only analyze a photograph of a certain time and place and it is still not clear if these results can be extrapolated to any context. A study conducted in Scotland, for example, it points out that hospitalization rates from patients infected with omicron and vaccinated with complete regimen they are up to two thirds smaller than among those affected by the delta variant. A Imperial College analysis, on the contrary, he finds that the risk of hospitalization among people who had already passed the disease it could be between 20% and 40% less than in other variants. In general, a research conducted in South Africa points out that the risk of hospitalization with omicron is reduced by up to 80% compared to delta and the risk of developing a severe disease decreases by around 30% compared to other lineages of the virus.

Although these data may, a priori, seem encouraging, it is not yet clear if this ‘good news’ is synonymous with peace of mind. First because, according to ‘Scientific American‘, the studies published to date are based on relatively small and probably unrepresentative analyzes. And second, because they could throw a misconception of the global danger of this variant. “Even if the risk of serious disease is low for an individual, the rapid spread of this variant could dangerously overload the health system,” the analysis wielded. “A small fraction of a very large number is still a large number“, qualifies, along the same lines, an article from the scientific journal ‘Nature’.

What symptoms does it cause?

On paper, everything indicates that omicron, like the rest of the variants, can cause asymptomatic infections to serious illnesses. The first studies and observations on the ground on it suggest that in most cases this lineage causes less severe symptoms than its predecessors. According data released by the largest insurer in South Africa, for example, a large part of citizens diagnosed with omicron developed mild symptoms What sore throat, stuffy nose, dry cough, and muscle pain. Some studies carried out to date suggest that, in general, vaccinated patients who contract the virus tend to present symptoms such as headache and fever, while unvaccinated patients who become infected tend to have more coughing and difficulty breathing, according to reports an analysis published in ‘The New York Times’.

One of the symptoms that seems to have changed with respect to the ‘classic coronavirus’ is the loss of taste and smell. At least that’s what the analysis of an outbreak detected in Oslo in which only 23% of those affected claimed to have lost their sense of smell and only 12% noticed loss of taste. Studies on the previous variants calculated that, on average, around 70% of patients infected with this virus had alterations in these senses. Probably due

Does it affect people who have been vaccinated and who have already passed the covid?

In part, yes. At least according to what the first studies on the subject point out and the analysis outbreaks observed in the last weeks. Everything points, then, to which omicron is a variant especially prone to reinfections. A very illustrative example is the explosion of cases recorded at Cornell University, where in less than a week more than 1,000 positives were registered on a campus where all students were immunized. A recent study from Imperial College point to what the risk of reinfection with omicron is 5.4 times higher than with delta. And this affects both people who have already passed the disease and those vaccinated. Of course, according to several works argue, booster doses are given in 55% to 80% of cases.

Related news

Another detail to take into account is that, according to the first studies, omicron is not only the variant that has spread the fastest across the globe; is also the one spreads faster from person to person. Various preliminary analyzes published in recent weeks suggest that in the case of this lineage, the time between exposure to the virus and the appearance of symptoms is in omicron ilower than other variants. If an infected with the alpha variant incubated the virus for five days and one affected by beta took about four days, with omicron it seems that this window is reduced to just three days. In practice, this implies that the shorter the incubation period, the faster a person becomes contagious. This could be the key to the explosive expansion of this variant.