A series of new studies confirmed the silver lining of omicron variants: Even though the number of cases soared to record levels, the number of severe cases and hospitalizations did not. Some scientists say these data mark a new, less worrying chapter in the pandemic.

“We are at a completely different stage now,” said Monica Gan, an immunologist at the University of California, San Francisco. “The virus will always be with us, but I hope this variant can produce such a large immunity, so that the pandemic can be calmed.”

A variant of omicron was discovered in South Africa more than a month ago, and experts warned that this situation still has enough time to change. But data from the past week showed that the combination of extensive immunity and numerous mutations resulted in a virus that caused a much more serious disease than the previous iteration. A South African study found that compared with patients admitted to the hospital during the third wave of omicron and delta-dominated, the fourth wave of virus infection has a 73% lower probability of serious illness. “Wendy Burgers, an immunologist at the University of Cape Town, said: “Due to the decoupling of hospitalizations and cases, the data is now very reliable.”

In the early days, most of the warnings about omicron were due to the large number of mutations in this variant, many of which occurred in the spike protein, which is the part of the virus that helps it invade the host cell. Early data shows that these mutations allow the virus not only to easily infect unvaccinated people, but also to escape the antibody response of previous infections and vaccines. But the question remains, once omicron crosses the first line of defense, how will it develop. Compared with the previous wave of Covid-19, several factors appear to reduce the toxicity or severity of omicron variants. One factor is the ability of the virus to infect the lungs. Covid infection usually starts in the nose and then spreads to the throat. A mild infection will not go further than the upper respiratory tract, but if the virus reaches the lungs, more severe symptoms will usually appear.

But five independent studies in the past week showed that this variant is not as susceptible to lung infections as previous variants. In a study published in the form of an online preprint by a large consortium of Japanese and American scientists, hamsters and mice infected with omicron suffered much less lung damage and were more likely to die than those infected with previous mutations. People are much smaller. Another study in Belgium found similar results in Syrian hamsters. It is well known that these hamsters suffer from particularly serious diseases due to previous iterations of the virus.

In Hong Kong, scientists studied a small number of patient lung tissue samples collected during surgery and found that omicron grew slower in these samples than other variants.

Bergs said that this change in virulence may be related to changes in the anatomical structure of the virus.

Complete News Source : Hindustan Times