Coronavirus: How long does immunity from booster doses last? Read on what experts have to say

Booster doses are the additional precautionary doses which are being administered currently to increase the memory of the immune system of the body against the coronavirus. The memory of the original vaccines wane after a certain duration and booster doses serve as memory enhancers.

The booster dose extends the protection against the COVID and keeps the body safe from the emerging variants of the virus.

Anyone above 18 years of age can get a booster dose. Booster or the precaution dose, as it is called in India, is currently being given to fully vaccinated frontline workers and senior citizens who are above 60 years of age. These people can get a booster dose 39 weeks from the second dose. Citizens aged 60 years or more and having co-morbidities, can also take precaution dose, but only after medical advice.

Booster dose helps the immunity system retain the memory of the pathogen and keeps it ready for any sort of similar attack in the future. Booster dose is essential when the effectiveness of the original vaccine dose starts to decrease.

In view of the emerging variants of coronavirus, booster doses are nothing less than a blessing. These vaccine shots protect the body from the upcoming mutating variant.

The effectiveness of vaccination and booster shots was seen during the third wave of the COVID wave. During this wave less hospitalization and severity was seen among patients. Though many scientists attribute the mild nature of the Omicron variant to be the reason behind it, many others say due to vaccination the risk of severity in most people was minimised.

This is the pressing question of the hour. The effect of the booster dose decreases after 10 weeks but the protection against severe diseases remains higher, say experts.

"In updated population data analysis, vaccine protection against mild disease has largely disappeared by 20 weeks after vaccination with a 2-dose primary course of vaccination. After a booster dose, protection initially increases to around 65 to 70% but drops to 45 to 50% from 10+ weeks..... Protection against severe disease is much higher – after a booster dose vaccine effectiveness against hospitalisation is estimated at 92% and remains high at 83% 10+ weeks after the booster dose," says a report from the UK health security agency released on January 14.

Another research study also hinted at the effectiveness of the booster doses against severe disease.

A US CDC research study of 241,204 emergency department/urgent care encounters, and 93,408 hospitalizations from August 2021 to January 2022 showed that the third dose of the vaccine was 91% effective against hospitalizations from COVID-19 up to two months after the shot; the effectiveness dropped to 78% after four months or more.

Vaccines are the best protection against the coronavirus at this time. With nothing else in hand and keeping in view the ever-mutating virus, everybody should get vaccinated along with the booster shots timely. Proper hygiene, wearing face masks and vaccination can only protect human beings from COVID.

In India till February 21, a total of 1,89,85,249 precaution doses have been administered to frontline workers and senior citizens.