Professor Luke O’Neill has said two new studies have indicated that immunity to Covid-19 could last for years.
The new research suggests important immune cells are present within the bone marrow of people who have been infected with the virus and have been vaccinated.
Since the beginning of the pandemic, questions have been raised about how long the vaccine will remain effective against the virus and whether or not people will need to receive a top-up jab each year.
These studies may put those fears to bed as they show that immunity to Covid lasts at least a year and possibly even a lifetime.
The reports looked at people who were exposed to the virus about a year previous.
One study, published in the journal Nature, said cells that retain a memory of the virus are present in the bone marrow and can produce antibodies whenever needed.
The study posted online at BioRxiv, found that these memory B cells continue to mature and strengthen for at least 12 months after the initial infection.
This means that people who have recovered from Covid and were later immunised will not need boosters. However, vaccinated people who were never infected by the virus will most likely need booster shots.
Scott Hensley, an immunologist at the University of Pennsylvania involved in the research, said, "The
papers are consistent with the growing body of literature that suggests that immunity elicited by
infection and vaccination for SARS-CoV-2 appears to be long-lived.”
He added: “The reason we get infected with common coronaviruses repetitively throughout life might have much more to do with variation of these viruses rather than immunity.”
The memory B cells produced in response to being infected with the virus and then being vaccinated are so strong they can even fight off variants of COVID, irradicating the need for booster shots.
Michael Nussenweig, an immunologist at Rockefeller University in New York who led the study on memory maturation, said, “People who were infected and get vaccinated really have a terrific response, a terrific set of antibodies, because they continue to evolve their antibodies… I expect that they will last for a long time.”
