Antibodies begin to decline on average six months after receiving booster dose of the Covid-19 vaccine. However, antibody levels are elevated in those with a history of Covid-19, said a recent study by Bangabandhu Sheikh Mujib Medical University (BSMMU).
"A study conducted one month after the first and second doses of the Covid-19 vaccine found that 98 percent of 223 people had antibodies," BSMMU VC Professor Dr. Sharfuddin said in a press conference on Monday.
"Those who had previously been infected with Covid, had more antibodies in their bodies. After 6 months of vaccination, the antibody levels decreased in most cases," he added.
Of those 30 vaccine recipients, 73 percent had a decrease in antibody levels, with the mean antibody level falling from 6,792 AU/mL to 3,963 AU/mL.
The VC also said that sufficient antibodies were not found in the body of two vaccine recipients. 100% of participants had antibodies after one month of taking the booster, and nearly all rebounded to antibody levels of 20,878 AU/mL.
"Six months after receiving the booster, 100% of participants still had antibodies, but almost all had antibody levels falling to a mean antibody level of 10,675.7 AU/mL. Among them, those with a history of Covid-19 have increased antibody levels," he concluded.
