AHMEDABAD: Results of the latest sero-positivity survey carried out by Ahmedabad Municipal Corporation (AMC) - fourth during the pandemic - brought both good and bad news for the city.
The good news first - out of 10,136 persons covered under the survey carried out in February, 2,830 or 28% were found to have developed IgG
antibodies against Covid-19. The number increased by 10% from the first
sero survey conducted in June 2020 where only 18% were found to have developed it.
The not-so-good news is that out of 359 confirmed positive Covid-19 recovered patients, only 233 or 65% were found to have antibodies. The rest have lost their safety cover which can make them susceptible for re-infection, said experts. Among the family contacts of patients, antibodies were found in less than half - 28% of the samples.
The survey results have come at a time when the state has again recorded a major daily surge at 1,961 – recording 20 cases every 15 minutes – on Thursday. Ahmedabad and Surat – both cities recording 500-plus cases – accounted for more than half (54%) of the daily cases.
Reflecting on the sero-positivity survey results, experts said that vaccination is the only way to increase ‘herd immunity’ which continues to elude the city. “Respective sero-positivity surveys have revealed that the community is not developing immunity against Corona. What's more, those who recovered from Covid-19 too are losing the immune cover," said a top AMC official. “In such a situation, getting vaccinated, wearing masks and maintaining social distancing protocols are the only way forward to fight with the pandemic.”
The Ahmedabad district administration also carried out its first sero-positivity survey in December 2020. The paper ‘Population based Sero-prevalence of SARS-CoV-2 Specific IgG Antibodies in Rural Ahmedabad – A Case Control Study’ by Arun Mahesh Babu, DDO Ahmedabad, and Dr. Shilpa Yadav, deputy CDHO, Ahmedabad, got published in International Journal of Science and Research (IJSR) recently.
The result indicated 25% overall sero-positivity in 2,301 samples taken. The figure included 46% among the positive patients, 21% among the patients’ relatives and 12% among the general population.