One dose of Pfizer vaccine may protect COVID-19 victims from reinfection: study – New York Post

People who had COVID-19 may only need one dose of Pfizer’s vaccine to be “sufficiently protected” against getting the virus again, a new study says.

The research, published in JAMA Network Open on Friday, compared the antibody levels of people who’d previously been infected with those who hadn’t been, after one and two doses of the double-dose Pfizer.

“We observed higher SARS-CoV-2 antibody levels in previously infected individuals after one dose of BNT162b2 (Pfizer) compared with infection-naive individuals after two doses,” said researchers from Chicago’s Rush University, who conducted the study.

The scientists said they found that giving previously infected people a second Pfizer shot did not “significantly increase” their antibody levels.

“Individuals with a documented prior COVID-19 infection may be sufficiently protected from reinfection after a single mRNA vaccine dose, which could free up availability of millions of additional doses,” the study concluded.

Pharmacy technicians prepare doses of the Pfizer-BioNTech vaccine at a mass COVID-19 vaccination.
The study found that giving previously infected people a second Pfizer shot did not “significantly increase” their antibody levels.
Michael Ciaglo/Getty Images

There is a severe vaccine shortage in some parts of the world, including India, where just over 7 percent of its nearly 1.4 billion population is fully immunized.

The latest reported research involved 29 Chicago-based residents who previously had COVID and 30 who had not. The average age of participants was 42 years, and about 75 percent were women.

The US Centers for Disease Control and Prevention recommends receiving two doses of the Pfizer vaccine 21 days apart.

Those age 12 and over can currently get the Pfizer vaccine, the CDC says.

Quantitative SARS-CoV-2 IgG levels at baseline (blue dots), 21 days after vaccine dose 1 (orange dots), and 28 days after vaccine dose 2 (brown dots) in infection-naive or previously infected individuals. Horizontal black bars represent mean quantitative IgG levels (AU/mL) within the indicated groups. Black dots represent 4 individuals with a previous positive SARS-CoV-2 polymerase chain reaction but did not have detectable SARS-CoV-2 IgG at baseline. Horizontal blue line denotes the assay limit of detection cutoff. Statistical analysis was performed using unpaired 2-tailed t test. AU indicates arbitrary unit.
People who had COVID-19 may only need one dose of Pfizer’s vaccine, a new study says.
Mark Anderson et al.