Antibodies fade over time: Moderna’s COVID-19 vaccine offers 3 month's immunity

A new study at the National Institute for Allergies and Infectious Diseases (NIAID) say that the Moderna COVID-19 vaccine will offer immunity for at least 3 months.

There are now many probable COVID-19 vaccines that are likely to hit the market in the near future. Countries are eagerly waiting for the rollout of vaccines though some skepticism remains in the minds of people regarding its efficacy. What many are wondering is the level and duration of immunity that it will afford a person. There have been many contradictory theories regarding this. Some say vaccines will confer immunity for 6 months to a year. Others are not very sure. But a new study by researchers at the National Institute for Allergies and Infectious Diseases (NIAID) says that the Moderna COVID-19 vaccine causes the human immune system to produce potent antibodies that endure for at least three months. The National Institute for Allergies and Infectious Diseases (NIAID) co-developed the vaccine along with Modern and the vaccine is said to have an efficacy rate of 94 per cent.

Antibodies fade over time

Researchers looked at the immune response of 34 adult participants, young and old, from the first stage of a clinical trial. The study, which is published in the New England Journal of Medicine says that the antibodies, which stop the COVID-19 virus from invading human cells, decline slightly over time, as expected, but they remained elevated in all participants 3 months after the booster vaccination. The vaccine, called mRNA-1273, is administered in two injections given 28 days apart. Even though the number of antibodies in the study subjects faded over time, it is not necessarily a cause for concern.

Not a cause of concern as body may produce new antibodies

NIAID director Anthony Fauci and other experts have said it is very likely that the immune system will remember the virus if re-exposed later on, and then produce new antibodies. Encouragingly, the vaccine activated a type of immune cell that should help out in the so-called memory response, but researchers caution that further study is needed to confirm this.

Strong antibody response after 90 days

According to experts, positives from the study include evidence that a relatively strong antibody response remains 90 days after the second dose of the vaccine. The amount of vaccine-produced antibodies was higher in younger patients than in older patients, but reasonably strong immune responses were still seen even in patients up to 70 years of age.

The science behind the Moderna vaccine

The Moderna vaccine, which will be reviewed by an advisory committee of the Food and Drug Administration (FDA) on December 17, is based on a new technology that uses genetic material in the form of mRNA (messenger ribonucleic acid). The mRNA is encased in a lipid molecule and injected into the arm, where it causes cells inside our muscles to build a surface protein of the coronavirus. This tricks the immune system into believing it's been infected with a microbe, and trains it to build the right kind of antibodies for when it encounters the real virus.

(With inputs from IANS)