A preliminary look at how vaccinated people would fare against the rapidly spreading Omicron version of the coronavirus was provided by a South African report.

While Omicron appears to weaken the Pfizer-BioNTech vaccine, laboratory studies suggest that those who have gotten a booster vaccination may be more protected.

Antibodies produced by vaccinated people were shown to be less effective at preventing the Omicron strain of coronavirus from infecting cells than other coronaviruses.

Results were described as “worrying,” but not life-threatening, by scientists. According to the research, those who have been vaccinated may be more susceptible to Omicron illnesses, which are rapidly spreading throughout South Africa and have now been detected in dozens of other countries.

Immune responses to vaccines go far beyond the production of antibodies. So the results of these studies are only a partial picture of how well the immunization protects against Omicron-related hospitalization and mortality.

In an interview, Alex Sigal, a virologist at the Africa Health Research Institute in Durban, South Africa, who led the research, said, “I’m not sure this is going to translate into systems collapsing.” It will be under control, in my opinion.

It took two weeks for Dr. Sigal and his team to cultivate the virus and test antibodies against it. “I’ll die of exhaustion if I don’t die from the virus,” he remarked.

As a child, Dr. Sigal feared that immunizations would not be able to protect him from disease. Antibodies from vaccines could have been rendered ineffective if the Omicron version had acquired a new method of accessing cells. As a result, “then all of our efforts would be in vain.”

That was not the case, though.

Immunoglobulins from six persons who received the Pfizer vaccine without having previously received Covid-19 were used in the study. Other patients who had been infected before to vaccination were also tested for antibodies.

All of the volunteers’ antibodies were shown to be less effective against Omicron than against an earlier variant of the coronavirus, according to researchers. As a whole, their antibodies’ efficacy against Omicron declined drastically, to around one-fifth of the amount reported when tested with an earlier strain of the virus. Omicron infections could be triggered by a low amount of antibodies.

That number, according to Rockefeller University virologist Theodora Hatziioannou, who was not engaged in the study, was not surprising. There was no big surprise here, she remarked.

The findings could shed light on some of Omicron’s most high-profile superspreading episodes. At least half of the 120 vaccinated guests at a Norwegian business Christmas party were infected with the virus.

On Tuesday afternoon, Dr. Sigal tweeted the results.

His team discovered a significant difference between the two groups of volunteers that they worked with. Six uninfected vaccinated patients had antibodies that were ineffective against Omicron. However, five out of six people who received Covid-19 before vaccination still had strong reactions.

People who are vaccinated after an infection develop larger amounts of antibodies than those who have not been infected, which may explain the discrepancy.

Research on Omicron boosters won’t reveal anything about their effectiveness until researchers personally test antibodies from patients who have received them. However, he was confident that the elevated antibody levels would be a good deterrent. That’s what he said.

According to an infectious disease researcher at Scripps Research Institute in California who was not involved with the new study: Booster injections are likely to help protect against the new variety.

For this reason I expect boosters to bring back higher levels of protection,” he stated. Clinical data from South Africa’s first Covid-19 outbreaks have shown that vaccinations or earlier infections can still protect against the more severe forms of this disease.”

Doctor Hatziioannou was unsure about boosters. She and her colleagues are conducting trials on antibodies from boosters to determine if they may provide the same level of protection as those who received vaccines during an infection. We’re going to have to wait for her answer.

It has been reported that both Pfizer and Moderna are now testing their vaccines against Omicron and expect to have Omicron-specific vaccinations available in around three months.

“The study shows that Omicron-targeted vaccines are urgently needed,” says Fred Hutchinson Cancer Research Center virologist Jesse Bloom. Omicron’s genetic information can be used to create a vaccine that can protect individuals against the virus, he added, despite the fact that there is some ambiguity about how widespread the variant would spread.

A significant decline in Omicron neutralizing antibody titers, he added, “certainly merits pushing forward with making Omicron-specific vaccines as fast as possible,” given the likelihood that it could spread broadly.