Between mid-June 2020 and early March 2021, the U.S. Red Cross tested more than 3.3 million non-vaccinated donations in 44 states for the presence of Covid-19 antibodies. Overall, approximately 7.5% of the donations tested at that time were positive for Covid-19 antibodies, meaning that the donors were probably infected with the coronavirus at some point.
The American Red Cross notes that “a positive antibody test result does not confirm infection or immunity,” but it may indicate whether a person has been exposed to the coronavirus, “regardless of whether an individual has developed symptoms.” The incidence of antibodies among unvaccinated blood donors has increased over time as cases have increased nationwide.
According to data shared via email with CNN, about 1.5% of the donations tested in the first week of July were positive for Covid-19 antibodies. This increased to almost 4% of the donations tested in the first week of October, about 12% of the donations tested in the first week of January and almost 21% of the donations tested in the first week of March is.
“Blood donors are not a random sample of the general population, but it is interesting,” said Dr. William Schaffner, a longtime advisor to the U.S. Centers for Disease Control and Vaccine Prevention, said.
Schaffner said there are two things we can impress about.
“The first is that a large portion of the U.S. population has experienced Covid, at least the blood donor population, knowingly or unknowingly. The other is that a large portion of the U.S. population does not have it – that’s the 80%,” he said. “So we can not just rely on the strategy to naturally prevent herd immunity. We need vaccination to make up to 80% of the population immune.”
Herd immunity is the point at which enough people are protected against a disease that it cannot spread through the population. This can be achieved when enough individuals have antibodies against the virus.
People who recover from the coronavirus have some protection against the virus, although scientists do not yet know how long it will last or how strong it is against the emerging coronavirus variants. The acquisition of a Covid-19 vaccine stimulates the immune system to provide artificial protection.
“Both contribute to the goal of becoming 80%,” Schaffner said.
The percentage of the U.S. population that needs to be vaccinated for the nation to achieve herd immunity remains an elusive number, ‘said Dr. Anthony Fauci, chief medical adviser to President Joe Biden, said at a White House briefing on Monday.
“We should not get so caught up in this elusive number of herd immunity. We should just be concerned about vaccinating as many people as quickly as possible,” said Fauci, director of the National Institute of Allergy and Infectious Diseases.
“Because herd immunity is still an elusive number, we made a prediction of what it would probably be. I have said it many times, somewhere between 70% and 85%, but we do not know for sure. So rather than figuring out why we are not saying that so many people can be vaccinated as quickly as possible, “Fauci said. “And every day that more than 2 million doses are taken in humans, we are getting closer and closer to controlling this pandemic.”
The latest findings from the U.S. Red Cross antibody trial among non-vaccinated donors reflect more general data.
According to a recent report from the Pew Research Center, 1 in 4 Americans say they have had Covid-19. One in three Spanish adults says they have had the virus, and younger adults are more likely to say they have the virus than older adults. The results suggest that the pandemic affected most Americans.
In the survey, 67% say they know someone who has been hospitalized or died of the virus. The response was reflected in the majority of all demographic groups.
According to Johns Hopkins University data, which represents about 9% of the population, about 29.5 million cases of Covid-19 have been reported in the United States. But experts estimate that the actual number of cases is much higher, consistent with the findings of the American Red Cross.
According to the U.S. Centers for Disease Control and Prevention, there were more than 83 million cases at the end of December, meaning more than a quarter of the population would be infected by the end of 2020.