Pune: After Delhi and Mumbai, the results of a serological survey conducted in Pune city were announced recently. Since the findings revealed that more than 51 per cent of the population had developed antibodies for COVID-19, Punekar started debating whether they have developed herd immunity against coronavirus.
Sakal Times spoke to Aarti Nagarkar from the Department of Health Sciences of Savitribai Phule Pune University and got answers to some questions raised by citizens.
Nagarkar said, "About 70 to 80 per cent of people have to be infected with the virus to develop herd immunity. This is not the case in the country yet. The survey in Pune tested antibodies in selected wards with high prevalence. So the survey findings have their own limits. Also, it needs to be studied and verified whether the antibody produced in the individual is capable of fighting coronavirus and how long it stays in the body. For that, it is necessary to conduct a survey again in a few months."
Why is the seroprevalence high in Pune?
The serological survey was conducted in Delhi and Mumbai in June and July, while in Pune it was conducted in July and August. The unlock phase has increased the spread of coronavirus, leading to an increase in the number of asymptomatic patients. Wards with high Covid-19 prevalence were also selected for the survey in the city. So the percentage went higher.
Why is it less prevalent among seniors?
The number of deaths of senior citizens has been high since the beginning of the pandemic. Therefore, the Pune Municipal Corporation had given instructions to senior citizens to stay home. At the same time, family members also took special care of the seniors. Scientists say that the prevalence of Covid-19 among senior citizens in Pune (over 66 years) is lower than in other cities.
Serological surveys in the country
1) New Delhi
Blood samples: 21,000
Samples containing antibodies: 23.8 per cent
Blood samples: 7,000
Samples containing antibodies: on average in citizens: 16 per cent, in slum dwellers: 57 per cent
Blood Samples: 1,664
Samples containing antibodies 51.5 per cent
4) India (Thyrocare Laboratory)
Blood samples: 2 lakh
Samples containing antibodies: 24 per cent
Aarti Nagarkar from Department of Health Sciences of Savitribai Phule Pune University said, "Local councillors, ward officials and social organizations helped a lot during the survey. It helped us collect samples. Such surveys will be of great help in studying the method of preparation and spread of future epidemics."