40% of recovered patients lack antibodies: AMC

AHMEDABAD: Municipal health authorities now warn Amdavadis of a possible second and even a third wave of Covid-19 infections, if basic rules of Covid hygiene are not followed. They found in their latest serology or antibody study that nearly 40% of 1,816 persons who had recovered from Covid did not develop, or lost the antibodies from their body. They also found that 68% of the 3,973 people who had contracted the virus from an infected person, including close family members, did not develop any antibodies against Covid-19.
“At this rate, a second or a third wave of Covid may follow, if precautions are not taken now,” warns an AMC official.

The antibody study conducted between August 15 and August 29 over a representative sample size of 10,000 people found that 23 % of the sampled population had Covid antibodies, while in the last survey conducted in June where a larger 30,000 people were sampled 17.6% people had developed antibodies. Another clear sign of people shedding antibodies over a period of time is seen in the municipal Central zone which had seen the outbreak in March-April where there is just a 3.2 % rise in population having developed antibodies now, compared to June. Another such zone is the East zone where there has been a marginal rise of 0.74% population having antibodies against Covid.
Dr Jay Shah, associate professor of AMC MET and Amit Parikh, HOD medicine, in SVP hospital said that the increase in positivity of 5.63% in the city after 1.5 months of earlier study, and in Unlock period, is very low.
A clear socio-economic difference could be seen in this antibody study. The posh North West and s South West zones, consisting of Jodhpur, Thaltej, Bodakdev, Gota, Ghatlodia, Sola, Science City and other surrounding areas showed a smaller percentage of population had developed Covid antibodies compared to populations in Central, East, North and parts of South zone.
But the bright spot in these posh areas is that there is a significant growth in the population showing presence of antibodies between the two surveys conducted in June and August.
“We are fine-tuning our results. One task is to find whether these tests were showing presence of other coronaviruses along with Covid-19 and another is to find how much time one takes to shed the antibodies. The Central zone and East zones are clear examples of shedding antibodies,” said a senior AMC official.