Facial nerve paralysis experienced after receiving the Pfizer-BioNTech vaccine shot against COVID-19 is a rare complication, an official has said.

Pfizer and partner BioNTech say in new research published Wednesday that its coronavirus vaccine is likely to be highly effective against a COVID-19 variant first identified in Britain late last year.

In their research paper, which has yet to be peer reviewed, the companies say the variant, which led to strict lockdowns in Britain and global travel restrictions, was effectively neutralized by the Pfizer-BioNTech vaccine.

Antibodies in more than a dozen patients over the age of 55 were reviewed for the study, they said.

The Pfizer-BioNTech vaccine works by building the body’s immune defenses against the coronavirus.

The research was posted to bioRxiv.

BioNTech CEO Ugur Sahin said the results of the study make it “very unlikely” that the variant will “escape” the Pfizer vaccine, which has been approved for use in the United States and abroad.

Researchers, however, said they’re still preparing for possible tweaks to their vaccine, if needed, to address further mutations of the coronavirus.

BioNTech said it would take it about six weeks to come up with a modified vaccine.

Moderna and AstraZeneca, who both have vaccines in distribution, said they are also testing theirs against the new variant, as well.

A different COVID-19 variant has also appeared in South Africa, against which some researchers say the currently available vaccines are not as effective.

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