COVID: five encouraging news about the omicron variant at the end of 2021

By Ignacio López-Goñi (The Conversation) *

The pandemic is not over, and we do not know how or when it will end. The level of uncertainty remains very high.

There are still many things we do not know about omicron and predicting how the virus will evolve is very risky, according to the professor of Microbiology, Ignacio López-Goñi, quoted by BBC Mundo.

We cannot rule out that even the situation will get worse, but we can also find some good news that allows us to continue being moderately optimistic.

1. Omicron infection poses a lower individual risk of hospitalization and death

There is increasing evidence that infection with this variant poses a lower risk of hospitalization. The first analyzes arriving from South Africa suggest a reduced risk of hospitalization among people infected with omicron compared to those infected with other variants, in the same period of time.

Also, once hospitalized, people infected with omicron had a reduced risk of serious illness compared to people infected with delta. Part of this reduction is likely due to a high immunity of the population.

In other countries the decoupling between those infected by omicron and the number of patients who enter the ICU and die from COVID-19 is also beginning to be illustrative, although it is still difficult to determine if the new variant is less virulent or if it is the effect of the immunity of the population (previous infections and vaccination), or by both things at the same time. In South Africa 65% fewer hospitalizations are reported; in Scotland, 60%; and in England, 40%.

A recent report from Imperial College London concludes that people who contract omicron are less likely to need hospital care compared to the variant delta.

The UK Health Security Agency, in its risk assessment report for the variant, already qualifies as “Moderate relative risk” the possibility of hospitalization for omicron, compared to delta (although he admits that there are no data yet on severity once in hospital or mortality).

2. In some countries cases plummet

In Norway, Holland, Belgium, Germany, South Africa or Austria the number of cases has already begun to decrease. It is possible that in several of these countries the effect of delta and omicron are mixed. Some, moreover, had been with restrictions.

But if we look at South Africa, where the omicron effect seems most evident, the increase has been explosive and exponential and the fall also appears to be very rapid. Some suggest four to five weeks of going up to the maximum and the same going down.

Perhaps this is the best news. Although the individual possibility of hospitalization is lower, a vertical wall of cases is tremendously dangerous for the health system and can lead to collapse. Therefore, the plummeting number of cases is very good news.

3. Vaccines protect against omicron

People with two doses remain protected against hospitalization, even if they have lost some of their protection against infection.

This is probably because most vaccines provide a cellular response which is not affected by this variant. There is also data showing that a third dose of messenger RNA vaccines has a potent neutralizing ability against omicron.

In addition, they are already being developed new universal vaccines against SARS-CoV-2 and all its variants, including omicron.

4. There are effective drugs against omicron

Magazine Science presents on its cover the drug Paxlovid, a new antiviral oral, a viral protease inhibitor, with an ability to reduce the risk of severe COVID-19 by more than 90%. This antiviral has already been approved by the FDA.

Paxlovid is an inhibitor of one of the SARS-CoV-2 proteases, called 3CL. The treatment is combined with another protease inhibitor, ritonavir, which has been used against HIV.

As the omicron variant does not present mutations in those proteins that are the target of Paxlovid, it is very likely that this drug is equally effective with the new variant in real life. At least, as reported by the Pfizer company, in vitro tests prove it.

But there is still more. The monoclonal antibody Sotrovimab from GSK also appears to be effective against omicron. It is an antibody that binds to a specific area (epitope) in SARS-CoV-2 shared with SARS-CoV-1 (the virus that causes SARS), indicating that this epitope is highly conserved. This makes it difficult for resistance to develop in the new variants.

Remdesivir, a viral RNA polymerase inhibitor, is another antiviral that in non-hospitalized patients with COVID-19 symptoms resulted in an 87% lower risk of hospitalization or death than placebo. Gilead, the manufacturer of Remdesivir, has carried out an analysis of the genetic information of omicron and has not found mutations that affect the target of this drug, so it is very likely that this antiviral remain active against this variant.

To date, the antiviral activity of Remdesivir has been confirmed in vitro against all other SARS-CoV-2 variants, including alpha, beta, gamma, delta, and epsilon.

5. Ómicron infects lung cells less

At least in cell models and in hamsters. It is true that we do not have the data in humans, but there are several preliminary studies that suggest that the omicron variant multiplies worse in lung cells, which could be indicative of its lower virulence (although it would be necessary to check what happens in other organs).

The situation is still very delicate, especially due to the explosive increase in cases that are leading the health system to collapse. If before 1 in 100 cases ended up in the hospital, now, thanks to vaccines, it is 1 in 1,000, but if the number of cases increases exponentially, hospitalizations will also increase and the system will collapse, as we are already seeing. That’s why we have to be very cautious.

However, this news, although preliminary, is good news and allows us to remain optimistic. 2020 was the year of the virus, 2021 the year of messenger RNA vaccines and hopefully 2022 the beginning of the end of the pandemic.

* Ignacio López-Goñi is Professor of Microbiology at the University of Navarra, Spain.