The first in-depth laboratory study of the omicron variant of the coronavirus offers a mixed bag of bad news and good news.

The bad: This variant is extremely slippery. It eludes a great deal of the protection provided by disease-fighting antibodies. That means people who previously recovered from a bout of covid-19 could be reinfected. And people who have been vaccinated could suffer breakthrough infections.

But the findings of the study, which tested the omicron variant of the coronavirus against the Pfizer-BioNTech vaccine, aren’t entirely bleak. The study, released Tuesday, found that even if the power of vaccines is diminished in the face of omicron, there’s still some protection afforded against the virus. And it suggests that booster shots could be key in the battle with the variant.

The implications of the findings for vaccine strategy are, at this point, unclear. It is a good sign that the Pfizer vaccine retains some punch against the omicron variant, but these lab experiments are a highly artificial way of testing how vaccines hold up.

Vaccine makers are working to reboot their vaccines with omicron-specific shots, but it is uncertain whether they will be needed or whether the protection from shots and boosters based on the strain of the virus that emerged two years ago will be sufficient.

The experimental study, from leading scientists in South Africa, was described in a preprint paper not yet peer-reviewed. The scientists reported a large, 41-fold drop in the virus-blocking ability of antibodies — “much more extensive escape” than seen against previous variants using similar experiments.

Still, the previous infection followed by vaccination or a booster is likely to “confer protection from severe disease in Omicron infection,” the study said.

The study is one of the first clues that will help inform pharmaceutical companies and policymakers trying to decide whether the global vaccination strategy needs to be updated with an omicron-specific shot.