30% individuals lose Covid vaccine-acquired immunity 6 months: Study

As much as 30 per cent individuals lose vaccine-acquired immunity after six months, according to a study conducted by AIG Hospitals along with the Asian Healthcare Foundation on Vaccine Immunity.

The study was conducted on 1,636 healthcare workers who were fully vaccinated against COVID-19, a press release from AIG Hospitals said.

"Our study results were at par with other global studies where we found that almost 30 per cent individuals had antibody levels below protective immunity level of 100 AU/ml after six months. These individuals were majorly above 40 years with co-morbidities like hypertension and diabetes. Out of the total, 6 per cent did not develop any immune protection at all," Dr D Nageshwar Reddy, Chairman, AIG Hospitals said.

The results clearly indicated that with age, immunity waning is directly proportional which means that younger people have more sustained antibody levels than the elderly population.

One of the most important results of the study showed that people above 40 years with co-morbidities like hypertension and diabetes have significantly less antibody response after six months of getting fully vaccinated, the release further said.

Individuals above 40 years with diabetes and hypertension of both genders may be at a higher risk of SARS-CoV-2 infection and these individuals should be prioritised for a booster dose after six months, AIG said.

At present, the nine-month gap for a precaution dose benefits 70 per cent of the population who can retain enough antibody levels beyond six months.

However, considering the scale of our country, the 30 per cent people especially those with co-morbid conditions like hypertension, diabetes, etc., who are more prone to develop an infection after six months of getting fully vaccinated should also be considered for the prevention dose, Dr Reddy added.