According to a study posted online on Monday, Covid-19 survivors had far higher antibody levels after both the first and second doses of the vaccine and might need only one shot.
“I think one vaccination should be sufficient,” said Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai and an author of the study, reports New York Times.
“This would also spare individuals from unnecessary pain when getting the second dose, and it would free up additional vaccine doses," he said.
While some scientists agree with his logic, others are more cautious. E. John Wherry, director of the University of Pennsylvania’s Institute for Immunology, said that before pushing for a change in policy, he would like to see data showing that the antibodies were able to stop the virus from replicating.
“Just because an antibody binds to a part of the virus does not mean it’s going to protect you from being infected,” he said.
The study also found that people who had previously been infected with the virus reported fatigue, headache, chills, fever, and muscle and joint pain after the first shot more frequently than those who had never been infected.
Also read: Moderna proposes filling vials with additional doses of Covid-19 vaccine
Side effects after vaccination are expected. The clinical trials of the authorized vaccines from Pfizer and Moderna, which included more than 30,000 participants each, showed that most people experience the worst side effects after the second dose
In the Moderna study, people who had previously been infected had fewer side effects than those who hadn’t.
Also, researchers are hearing from a growing number of people who felt ill after one shot.
That matches what Dr Krammer and his colleagues found in their new study, which has not yet been published in a scientific journal. The researchers assessed symptoms after vaccination in 231 people, of whom 83 had previously been infected, and 148 had not. Both groups widely reported experiencing pain at the injection site after the first dose. But those who had been infected before more often reported fatigue, headache and chills.
The team also looked at how the immune system responded to the vaccine in 109 people — 68 of whom had not previously been infected and 41 who had — and found a more robust antibody response in the latter group. The numbers, however, are small, and so the study’s conclusions will need to be further investigated with more research, experts said.
