Omicron, a new strain of the corona virus, has traveled the entire earth in a month, astonishing experts. But it is not entirely clear whether the severity of the infection is lower for unvaccinated and immunocompromised individuals.
Omicron is spreading faster than any other known virus. Just one month after its detection in South Africa, a new strain of the corona virus is now spreading around the world with more cases than ever before. Robbie Batacharya, an infectious disease specialist at Massachusetts General Hospital in the United States, called the speed of omicron release “extraordinary.” Batacharya has performed an approximate calculation to show the power of omicron transmission to show the race between omicron and measles, another more contagious virus in the world.
A person with measles infects an average of 15 people if those around them are not vaccinated, compared to 6 in the case of omicrons. But the key is how long it takes for people who got the infection from the first person to spread it to others. This takes about 12 days for measles. In the case of omicron, it only takes 4 to 5 days. One case of measles causes 15 cases in 12 days. But one case of omicron causes 6 more cases in 4 days, 36 cases in 8 days and 216 cases in 12 days.
In the real world, of course, the new version of the corona virus strikes people who have been vaccinated or those who have already been infected with Covidus 19, and it slows down its spread. Therefore, Batacharya believes that each person infected with omicron infects only three other people. This figure is similar to the calculated figure for the primary virus in Wuhan, China, which spread rapidly on a planet without immune defenses and inhibitory measures. Batacharya warned:
At present, the simple exponential growth model still shows that 14 million people become infected from an infected case within 60 days. However, in a population that does not have a specific defense, the figure for measles is 760,000.
Anton Arcorca, a physician and historian who studies past epidemics, is shocked by the rapid spread of omicrons. Erkorka, director of the Museum of Basque Medical History, recalls that it took years for the Black Death (14th century) and cholera (19th century) to spread around the world. The world-famous Russian flu outbreak of 1889, caused by another coronavirus, lasted three months, much like the initial SARS-CoV-2, which was detected in Wuhan in December 2019 and spread everywhere. “The Omicron species has broken this record for the speed of propagation,” Arcorca said.
William Hange, an epidemiologist and director of the Center for Infectious Diseases Dynamics at Harvard University, agrees. “Certainly Omicron has the highest rate of spread among the viruses we have been able to examine in this level of detail,” he said.
One well-studied micron outbreak was a party in Norway that began with a party that had just arrived from South Africa and ended with the contamination of at least 81 of the 117 party attendees.
There is no doubt about the unprecedented spread of omicrons, but what is less clear is the impact of the tsunami on the vulnerability of people in populations with high vaccination rates.
In Spain, almost 100% of people 70 years of age and older are vaccinated. Omicron can infect vaccinated people, but vaccines still prevent serious illness. This has been confirmed by a recent study led by Dutch virologist Korin Gertzonksel of Erasmus University in the Netherlands.
Of course, the individual risk is much lower than the risk of previous species, and with so many infections, the daily admission rate in Spain’s intensive care units is now half that during the worst wave of infections in January 2021, when someone He was not vaccinated, it happened.
Two weeks ago, Hange and Batacharya published an article on the difficulty of determining the true severity of omicrone. Batacharya now points out that the severity of the new species in people who have not been vaccinated or previously infected is probably 25 percent lower than in Delta, which was identified in India a year ago. “According to several studies, the intensity of alpha (detected in the UK in late 2020) was 50% lower than that of Delta,” Batacharia said. “Given the rapid release of omicrons, this species is likely to do a lot of damage in a shorter period of time.”
Less mortality
6 Preliminary studies show that omicrone can attack the upper respiratory tract more easily, but is less effective in infecting the lungs. This helps explain its greater contagiousness and lower mortality.
A team of virologists at the University of Hong Kong calculated in a laboratory study that omicrons multiplied 70 times faster than delta in human bronchi but were 10 times less effective at infecting the lungs.
Ravindra Gupta, a microbiologist at the University of Cambridge in the United Kingdom, confirms this trend, and other articles published by virologists at various universities show that omicrons have less ability to infect the lungs of hamsters and genetically modified mice.
Harvard University epidemiologist Hange continues to believe that omicrons look much milder because people have more defenses because of vaccination or previous exposure to the virus. He said:
Many omicron infections are especially mild in vaccinated people and are comparable to short-term colds. The problem is that there will be serious cases, and since it is so contagious, the total number of cases that require medical care will put pressure on the health system.
According to British health officials, 40% of people hospitalized in London for Omicron infection have not been vaccinated. Hange pointed to another temporary figure. He said:
In the case of omicrons, the length of hospital stay seems to be generally shorter and the likelihood of needing supplemental oxygen is lower. But it should be noted that we have not yet seen many infections in the elderly.
In Spain, the 14-day cumulative prevalence is about 2,900 cases per 100,000 people in their third decade of life, but 465 cases per 100,000 people in their ninth decade of life. However, these figures are rising sharply due to increased exposure during the Christmas holidays.
Higher immunity
Aris Katzourakis, a virologist at the University of Oxford in the UK, is also skeptical. He said:
I’m still not convinced that omicrons are inherently lighter than they originally appeared in Wuhan. The omicron appears to be milder than the delta, but this is because the delta evolved to be more intense than its ancestral form. Higher safety seems to be the most logical explanation for the reduction in severity observed in the population.
A new preliminary study released Dec. 27 by researchers at the University of KwaZulu-Natal in South Africa shows that omicron infection protects against delta species. But this study was done on only 13 people, most of whom were young and vaccinated, so it is too early to draw conclusions.
The study’s lead author, Alex Seagal, acknowledges that the protective effect of omicron in unvaccinated people is not seen in his study, but his findings reinforce the misconception that omicron causes a simple cold that will work as a natural vaccine for the world. Katzourakis warned on social media:
I like people not to talk about omicrons as if the attenuated vaccine is alive. This is not the case. Get vaccinated, get a booster dose, and take precautions to prevent infection.
“We still do not know much about Omicron to reduce precautions,” said Tedros Adhanum, director general of the World Health Organization, at a recent news conference. He said:
Omicrons are expanding at a rate never seen before in any of the species. We are worried that people will take Omicron lightly and ignore it. Even if the severity of omicron-induced disease is less, a large number of cases can once again put undue pressure on health systems.
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