How important are vaccine boosters?
Coronavirus vaccination is underway in full swing, but an increase in breakthrough infections has become a major concern recently. While emerging variants and lax precautions are suspected to be main reasons behind rising number of infections, experts believe that waning effectiveness of antibodies from COVID vaccines may be leading to a rise in the possibility of infections.
In such scenarios, the demand for a booster shot has increased in many parts of the world. India's Bharat Biotech is currently in the process of developing a vaccine booster, while Israel and the United States of America have started offering booster shots to adults at risk.
COVID booster shot: What is it?
Up until now, COVID vaccines have been administered in two doses, except for Johnson & Johnson's Janssen, which is a single-shot COVID vaccine.
However, researchers, across the globe, are expanding the horizon and are looking forward to developing a ‘booster’ or a third COVID dose to ensure higher efficacy. Given the emergence of new variants, with Delta variant wreaking havoc in and around the world, a booster shot is expected to provide better protection against the deadly virus and its variants. A booster shot is said to re-expose a person's immune system to the immunizing antigen, the memory of which (after the previous dose) could have been lost over a period of time.
Is it necessary?
According to experts, it is normal for virus-fighting antibodies induced by COVID vaccines to wane over a period of time. Given the emerging variants, fully vaccinated individuals continue to remain at risk. Even after receiving two doses of the vaccine, there have been many cases of breakthrough infections, which have become a cause for concern.
However, this does not mean that the vaccines are less effective against the virus. As per the Centre for Disease Control and Prevention (CDC), "COVID-19 vaccines are working very well to prevent severe illness, hospitalization, and death, even against the widely circulating Delta variant. However, with the Delta variant, public health experts are starting to see reduced protection against mild and moderate disease."
This has therefore ignited a lot of talks around the need for vaccine boosters.
Who will require a booster shot against COVID-19?
As COVID-19 vaccines were first made available to the most vulnerable in the society, similarly, COVID booster dose will be prioritized among people with compromised immunity.
The CDC has provided a list for people who are eligible for the vaccine as of now.
- People receiving treatment for tumours and blood cancer
- Advanced or untreated HIV infection
- Those who have undergone an organ transplant
- People who have received a stem cell transplant and are taking immunosuppressant medications
- People dealing with moderate or severe primary immunodeficiency
- People who are under high-dose corticosteroids treatment or any other drug that can suppress immunity
How soon should you get your booster shot?
The novel coronavirus continues to be rampant and the new emerging variants only add to the woes. Since immunocompromised people are at a greater risk to contract the virus and develop severe illnesses, it is important that vaccines are prioritized and booster shots should be taken as and when they're available in India.
Currently, the United States of America and Israel are the only countries who have approved the administration of a third mRNA booster shot for people who have a compromised immunity.