What scientists are doing now to understand the Omicron variant

Colored scanning electron micrographs of cells infected with SARS-CoV-2 particles (green) (purple) isolated from patient samples. Photo: NIAID / Flickr, CC BY 2.0

• The goal is to see how well antibodies from real people infected or vaccinated with COVID-19 can suppress Omicrons in laboratory Petri dishes.
• We are waiting for these important results: how effective are existing antibody vs. boosters, and how effective are vaccines after recovery from COVID-19?
• The initial early results are back, and antibodies against the early mutants appear to be less successful in blocking Omicron.

Scientists around the world have been competing to learn more about the new Omicron strain of SARS-CoV-2. “Variant of concern” According to WHO, November 26, 2021. Authorities have asked whether recently emerging coronavirus variants are more contagious than Delta and other previous variants and cause more or less serious COVID-19, and whether current vaccines can prevent it. I warned that it would take a few weeks to find out.

Peter Casson A virologist and biophysicist at the University of Virginia, he studies how viruses such as SARS-CoV-2 can invade cells and what they can do to stop them. Here he explains what lab-based scientists are doing to answer unanswered questions about Omicron.

Does previous immunity protect from Omicron?

These are the results of the important labs that everyone has been waiting for. How effective are the antibodies that people already have to fight Omicron? Are you protected if you get a booster shot? Or what if you were infected with COVID-19 and then vaccinated?

The goal is to see how well antibodies from real people infected with or vaccinated against COVID-19 can suppress the omicrons contained in the laboratory Petri dishes. Scientists predict that antibodies from people exposed to other mutants will not work well against Omicron because of the mutation, but how bad it is to stop the virus, yet. You need to measure if it is enough.

To answer these questions, most researchers first create a version of the SARS-CoV-2 virus that can invade cells. Do not reproduce..Several specialized labs Extra level of biosecurity Use the actual virus. Scientists add antibodies from the blood of people vaccinated with or recovered from COVID-19 to the virus. It is then mixed with human lung cells to see if the antibody can block the virus from infecting the cells.

My laboratory does this kind of work SARS-CoV-2 And others Emergent virus..Researchers have tested antibodies using these established techniques After COVID-19 recovery, And with various vaccines Various variations..

If antibodies made by people against previous variants cannot stop Omicron from infecting lung cells in the laboratory, those antibodies will probably not protect people around the world.

The initial initial results are back, and the antibodies against the early mutants Not very successful When blocking Omicron. The researchers collected antibodies from six people who were vaccinated twice each and another six who were vaccinated twice each and recovered from their previous COVID-19 infection. Based on the amount of antibody needed to prevent infection, the antibodies of people in both groups had about 40-fold worse omicron arrest than the original SARS-COV-2 strain. However, those whose immune system saw the virus three times, that is, who had been double vaccinated and recovered from COVID-19, had antibody levels high enough to stop the infection.

People who receive the booster vaccine will have a similar or higher level of immunity and will be at least moderately protected from Omicron. However, it should be tested.Pfizer Said Their initial results are in line with this prediction, but the data have not yet been published. All of this work has not yet been peer reviewed and is still very preliminary.

Scientists need to determine how good an antibody is to reduce the “neutralizing titer” or block the virus in the laboratory.Vaccine efficacyOr how likely is a vaccinated person to be infected with COVID-19 compared to an unvaccinated person?Scientists have better antibodies handle It is a more effective vaccine, but it is necessary to determine the exact numerical relationship.

How contagious is Omicron compared to Delta?

Past pandemic years have shown that infectivity, or infectivity, is an important factor in determining whether a variant of the coronavirus predominates. Delta’s transmissibility made it the predominant variant of the present, as it simply outperformed others. However, the situation can change over time.

A fundamental element of the virus’s “life” cycle is to invade cells, make more viruses, and escape.Scientists can measure and report on each of these stages in the lab What aspect Variants are more or less communicable. In addition to improving binding to human cells, some mutations enhance the packaging of new viruses and the delivery of their genes when the virus invades the cells.

Laboratory-based science helps people understand the biology behind why mutants are more or less contagious, but nature is now conducting much larger real-world experiments.Disease surveillance data from UK When Other countries If Delta was dominant, it suggests that Omicron has gained a share and could eventually replace Delta.

How this works depends on factors such as the number of vaccinated people and previously distributed variants, but this news is concerned about how good Omicron is. It has been.

Does Omicron make people more or less sick?

Again, this is a question that thousands of people infected with Omicron answer much faster than working in the lab. However, it is important to remember that natural experiments are not as carefully controlled as laboratory experiments. Working in the exact lab can help explain why Omicron is different, but the first answer here is from the hospital.

Laboratory-based scientists work with hospitals to analyze why patients infected with Omicron get more or less ill.Some early numbers are for the first Omicron case Almost calmHowever, public health officials warn: most cases of all COVID-19 mutants are mild, and many of the cases infected with Omicron so far. Young.. The number of hospitalizations tends to increase somewhat after the initial increase in cases. Therefore, it will take some time to answer this question.

How are lab and public health data complemented?

The laboratory will provide the first results on immunoprotection against Omicron, which will be followed up with public health data that are likely to confirm the laboratory results. Public health data provide initial results regarding infectivity and disease severity, which are then explained by test results.

Even after the initial response from public health data is available, results that help understand why these changes have occurred and predict what future mutations will do are still important. How do authorities declare a variant of concern in the first place? It combines public health data with understanding from the lab.

What do we already know?

Variants of SARS-CoV-2 do not change the laws of physics and biology. They cannot jump over skyscrapers at once. Physical barriers such as premium masks and good ventilation block the virus. And perhaps the vaccine will continue to provide some protection.The question is how much and what the world needs to do Change the current vaccine Or just offer more of them.

Peter Kasson is an associate professor of molecular physiology and biomedical engineering at the University of Virginia.

This article was first published conversation Reissued here under a Creative Commons license.