Micron is not a blank copy of the coronavirus. The latest studies show that the variable conquering the globe does not have a drastically lower intrinsic attractiveness, but that this omicron strikes a group with unique properties. These days, the delta variant, identified a year ago in India, and the burgeoning Omicron, discovered a month ago in South Africa, coexist. Cohorts of scientists are trying to compare the risks of hospitalization in a group of similar people, but half have omicrons and half have deltas. In these analyzes the risk of the new variant appears to be lower, but Study from Imperial College London Wednesday’s post shows the key: Up to 40% of omicron cases could be in people who have already outgrown the virus, compared to 8% in Delta. Both types are very contagious among the unvaccinated, but Omicron is also able to infect many people who already have good defenses, which is why it appears to be less dangerous.

The big question is whether the new variant is really lighter than the old one. American biologist Marm Kilpatrick Candid: “The short answer is we still don’t know.” An Imperial College report shows that the probability of ending up in the hospital with an Omicron is up to 45% less than the probability of having a delta. However, if the influence of the greater number of mild cases due to infection is excluded, the authors calculate that your probability of developing an oomicron could only be between 2% and 35% less than delta. This small difference in severity would be greatly outweighed by the large number of cases caused by Omicron, which would result in many hospital admissions. If it’s really milder, it’s not milder, so it’s not a reason to be complacent about the increase in omicron cases,” warns Kilpatrick, of the University of California, Santa Cruz (USA).

The problem is the size of the next wave. If the probability that you will end up in hospital with Omicron is 50% less than that of Delta, but cases are doubling every two days, within two days there will be the same number of patients being admitted with the Covid virus, according to the has revealed Epidemiology world Deepti Gordasanifrom Queen Mary University of London. Cases of omicron have already doubled every two days in many countries. The Institute for Health Metrics and Evaluation at the University of Washington calculated that Wednesday 3000 million people They will catch the new variant in the next three months. If these estimates are confirmed, then in the next quarter there will be as many cases as in two years of the pandemic.

If it’s really milder, it’s not milder, so there’s no reason to feel complacent.

Marm Kilpatrick, American biologist

Aside from the uncertainty about the true true severity of omicron, the good news is that in today’s world its effects are much lower, thanks to the combined effect of vaccination, natural defenses from past infections and the potential for increased virus virulence. Models from the University of Washington estimate that 90% of omicron cases are It will be asymptomaticCompared to 40% of previous variants.

An Imperial College analysis found that people who got at least two doses of the Pfizer, Moderna or AstraZeneca vaccines remain “significantly protected” from severe COVID, even though Omicron has a greater ability than Delta to cause mild infections in those vaccinated. The study shows that if a person vaccinated with two doses of Pfizer becomes infected, their likelihood of developing severe symptoms is 80% less than the likelihood of an unvaccinated person developing delta. With two doses of AstraZeneca it is about 65% lower. The third dose also increases protection, which tends to decrease over time. In Spain, almost 100% of those over the age of 70 were vaccinated. This is the main reason why positive cases exceeded the epidemic record – 60 thousand cases were recorded daily – without noticing a parallel increase in hospitalizations.

According to South Africa’s National Institute of Infectious Diseases this Tuesday, the risk of hospitalization via Omicron is 80% less than with deltaBut his study compares the current wave to the one that occurred five months ago, when the rate of vaccination was lower and there was also less natural immunity than previous infections. The South African analysis does not compare the severity of current omicron and delta cases, as does the Imperial College report.

Preliminary analysis of Scotland data Pointing in the same direction. Omicron cases have a 60% lower risk of ending up in the hospital than those in Delta, an effect attributed to the new variant’s greater ability to infect people who already have natural defences. The Scottish study, published by the University of Edinburgh on Wednesday, indicates that a third dose of the vaccine reduces the risk of developing a symptomatic infection by 57% compared to taking just two doses more than six months ago. The authors also calculate that the ability of an omicron to re-infect people who have already passed COVID is 10 times that of a delta.

There is not enough data to know if omicron is inherently less acute than delta

Frode Forland, a Norwegian doctor

One of the best-studied omicron outbreaks occurred on November 26 in Party in Oslo (Norway). At least 81 of the 117 participants became infected and only one was asymptomatic. The rest, with an average age of 38 and a full vaccination schedule, had mainly cough, fatigue, runny nose, sore throat and fever. norwegian doctor Frode Forland He states that there is no record of hospitalization, but stresses that it is too early to draw conclusions. “There is not enough data to know if omicron is inherently less severe than delta,” warns Forland of the Norwegian Institute of Public Health.

The doctor declares his “extreme concern” about the overwhelming transmissibility of the new variant. “Many infected people in such a short time will cause a very high peak and we will have difficulties treating a lot of people, even if it’s a really milder Omicron,” he warns. Epidemiology world William Hanage, from Harvard University (USA), summed it up with a very pictorial phrase In British newspapers Watchman: “The difference between a touch and a slap is very much the speed.”

Two epidemiologists from La Princesa Hospital in Madrid, Juan Soriano and Julio Ancocchia, and two Italian colleagues They calculated The peak of this wave in Europe will reach on January 15, with 400,000 cases per day. “The debate about whether Omicron is more or less dangerous is a futile one, because the virus is still very bad. It can take you to the ICU and kill you,” Soriano says. “In addition, primary care clinics and outpatient clinics have been,” he warns. Too saturated indeed, but now collapsed.” This is one of the effects of omicron’s great transmissibility: in London, 7% of doctors You are on leave due to Covid illness or close contact with the case.

Soriano is also concerned about the persistent coronavirus: symptoms that can last for months, whether it’s respiratory problems, fatigue or mental fog that makes reading difficult. One out of every six infections has symptoms Ends with continuous covid”, notes Soriano, citing data from previous variables, because it is still too early to know the long-term effects of omicron. “People play the Christmas lottery thinking they will win, even though the probability of winning the jackpot is one in 100,000. However, it is It is believed that the persistent virus, which is one in six, will not touch him. The epidemiologist concludes that humans assess risks very poorly.

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