The second phase of the sixth sero survey in Mumbai has shown that persons who have received precaution doses of the COVID-19 vaccine have significantly higher antibodies than those who took two doses of the vaccine, a Brihanmumbai Municipal Corporation (BMC) official said.
The second phase was conducted in the months of September and October last year and included a follow-up of those who had taken part in the first phase, a BMC release said.
About 88 per cent, or 2,733 participants in phase-I survey, took part in the second phase. This comprised 50 per cent front line workers and 50 per cent healthcare workers. Out of the 2, 733 participants, 59 per cent were aged 25 to 45 years, while 41 per cent were in the 45-65 segment. Of the total, 57 per cent were males and 43 per cent were females, it said
Only 0.7 per cent participants had not received any dose of the COVID-19 vaccine, while 1.3 per cent had taken a single dose, 55 per cent participants had taken both the doses and 43 per cent had taken the precautionary dose. The survey found 99.9 per cent participants to be seropositive irrespective of how many doses they had taken, it added.
Those who took two vaccine doses or those who received a precaution dose, with a history of COVID-19, showed significantly higher titre (a measure of antibody concentration) than those with no known history of COVID-19 in both cases, the release said.