COVID-19 SCIENCE UPDATES

Following AstraZeneca with Pfizer shot boosts antibody response; COVID-19, not Pfizer's vaccine, tied to Bell's palsy

The following is a roundup of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the illness caused by the virus.

Following AstraZeneca with Pfizer shot boosts antibody response

Giving a dose of the Pfizer/BioNTech COVID-19 vaccine four weeks after an AstraZeneca shot produces better immune responses than a second dose of AstraZeneca's, Oxford University researchers said on Monday.

In a study of 830 older adults, mixed two-dose schedules of AstraZeneca and Pfizer vaccines produced higher concentrations of antibodies against the coronavirus that a full schedule of the AstraZeneca shot.

The most effective approach – two doses of Pfizer/BioNTech mRNA vaccine - produced levels of antibodies about 10 times higher than two doses of the AstraZeneca vaccine, the researchers reported on Friday in a Lancet preprint.

However, the AstraZeneca shot followed by a Pfizer jab induced antibody levels about as high as two Pfizer/BioNTech doses.

Giving the Pfizer shot first, followed by AstraZeneca's, was not as successful.

That combination yielded antibody levels higher than two AstraZeneca shots but lower than two doses of the Pfizer vaccine.

There were no new safety issues uncovered in the study.

Matthew Snape, the Oxford professor behind the trial, said the findings could be used to give flexibility to vaccine rollouts but were not significant enough to recommend a broad shift away from clinically approved schedules.

COVID-19, not Pfizer's vaccine, tied to Bell's palsy

The Pfizer/BioNTech vaccine has not been linked with a higher risk for the facial nerve paralysis known as Bell's palsy, but COVID-19 itself does increase the risk, suggest two separate studies published on Thursday in JAMA Otolaryngology-Head and Neck Surgery.

One study involved 110 people in Israel who received the Pfizer vaccine, including 37 in whom the characteristic facial droop developed on average nine days after the first dose or 14 days after the second.

After accounting for underlying risk factors for Bell's palsy, the researchers concluded the vaccine itself did not increase the risk.

Furthermore, they found, rates of Bell's palsy had not gone up during the vaccine rollout. In the second study, researchers compared Bell's palsy rates among roughly 348,000 patients with COVID-19 and roughly 63,500 people who had been vaccinated against the coronavirus.

The Bell's palsy risk was nearly seven times higher in those with COVID-19, they found. "Our data suggest that rates of facial nerve palsy are higher in patients who are positive for COVID-19, and this incidence exceeds the reported incidence of Bell's Palsy with the COVID-19 vaccine," said Dr. Akina Tamaki of University Hospitals Cleveland Medical Center, who coauthored that study.

"Taken together, it supports that the vaccine is safe from a facial nerve paralysis standpoint." -- Reuters