As the UK started its coronavirus vaccine program this week, fears arose after participants of a US trials of the Pfizer-BioNTech vaccine developed Bell’s palsy.
Bell’s palsy is a temporary paralysis of facial muscles that leads to drooping of one side of the face. It usually occurs when a nerve that controls the muscles becomes inflamed, swollen or compressed.
The condition resembles a stroke, with most patients watching helplessly as one side of their face droops and their muscles go limp. In some rare situations, both sides of the face may become paralyzed. It is unclear what causes Bell’s palsy, although the temporary paralysis usually goes away on its own.

The vaccine, codenamed BNT162b2, was in trial stage in the US when four out of the more than 21,000 participants who received the vaccine suffered facial paralysis.
The Food and Drug Administration (FDA) regulators said there wasn’t any clear indication the vaccine caused Bell’s palsy, but warned that doctors should watch for the alarming side effect. FDA also asked Pfizer to continue keeping tab on how many people it strikes.
Pfizer chief executive Albert Bourla said the pharmaceutical giant did not “cut any corners” while rolling out the vaccines.
The vaccine has “been tested in the exact same way as we are testing any vaccine that is circulating out there,” Bourla asserted.
He added, “this vaccine actually was tested, because of the scrutiny, with even higher standards in terms of how we do things.”
The UK’s Medicines and Healthcare products Regulatory Agency, stated that the safety profile of Pfizer-BioNTech vaccine is similar to other kinds of routinely used inoculations.
“No vaccine will be authorized for supply in the country without fulfilling the mandated standards for safety, quality and efficacy,” the British healthcare regulator said.
The UK is the first country to approve and administer the Pfizer-BioNTech coronavirus vaccine. It started giving out its first doses on Tuesday to elders affected by the disease.
According to FDA’s review, the two-dose vaccine is about 50 percent effective even after just the first injection. The vaccine is believed to be 95 percent effective after the second dose, which is administered three weeks after.
FDA also found that the jab reduced the risk of severe COVID-19 symptoms after the first dose.
The positive review sets the stage for a decision to allow the vaccine’s initial use within days in the US. The country is has the highest number of infections, having set a new single-day record on Wednesday with 3000 deaths. According to statistics, an average of over 200,000 Americans per day were testing positive for the virus.
The nationwide spike is likely to worsen during holiday gatherings in the coming weeks.