Preliminary results of a clinical study suggest that people who received the single-dose Johnson & Johnson COVID vaccine may get better protection from a booster shot from either the Pfizer or Moderna vaccine.
A study conducted by the U.S. National Institutes of Health found that those who received the Johnson & Johnson vaccine had a more than 76-fold rise in their antibody levels after receiving a Moderna booster, compared with a 35-fold rise in their antibody levels after receiving a Pfizer booster shot.
Researchers say those who received a second Johnson & Johnson shot saw only a fourfold rise in their antibody levels.
The revelations come as an advisory panel of the Food and Drug Administration begins two days of meetings Thursday on whether to recommend booster shots of the Johnson & Johnson vaccine and the two-dose Moderna vaccine.
The Centers for Disease Control and Prevention has already cleared booster doses of the two-dose Pfizer vaccine for certain people starting at six months after their last shot.
A related study conducted by researchers at Imperial College London found evidence of so-called breakthrough infections more than three months after full vaccination.
The scientists found that COVID-19 infections were three to four times higher among unvaccinated people than those who had received two shots, based on random samples of more than 100,000 swabs. The study revealed that infection rates dropped from 1.76 percent in the vaccinated to just 0.35 percent three months after the second dose, but rose again over one-half of one percent between three and six months after the second shot.
The International Federation of Red Cross is praising the tiny Pacific nation of Palau with the world’s highest percentage of people fully vaccinated against the coronavirus. The IFRC cited government figures showing 99% of the archipelago’s population over 12 years of age has had two shots of either the Pfizer or Moderna vaccine.
Another Pacific island nation with nearly all of its population fully inoculated includes the Cook Islands with 96%, while Fiji has 96% of its eligible population having received one dose.
By comparison, less than 10% of the Solomon Islands’ 650,000 citizens and Kiribati’s 100,000 residents are vaccinated, while less than 1% of the population of Papua New Guinea is fully vaccinated, according to figures released on the website Our World in Data figures.