Half of Bhubaneswar’s population may have been exposed to the SARS-CoV-2 infection and developed antibodies, finds the third sero-survey conducted by the Regional Medical Research Laboratory (RMRC).
“The present and third sero-survey was carried out from October 16 to 18. As many as 1,403 samples were taken for tests in 25 clusters or wards of city. We have found that antibody has formed in 50% of the city’s population,” said Sanghamitra Pati, Director of RMRC, an Indian Council of Medical Research (ICMR) institute, here on Friday.
Sero-surveys are conducted by drawing blood samples and checking for a specific class of antibodies that appear within two weeks of an infection.
First round of survey
“In the first round of sero-survey conducted in Bhubaneswar on July 11, we had found 1.42% sero-prevalence in community level. Since more than 98% were not exposed, it was then decided to do another survey. The sero-survey done on August 28 indicated sero-prevalence at 5.1%,” said Dr. Pati.
“The present October 16-18 survey corresponds to infection status prior to three weeks ago that means if fresh sero-survey is carried out, the sero-prevalence would go up further,” she observed.
According to findings, there has been variation in sero-prevalence from one ward to another. For example, 28% prevalence was found in Ward-55 while it was 63% in Ward-16. In 10 out of 25 wards, the sero-prevalence was above 50%. There was above 60% sero-prevalence in five wards.
The survey did not find variation as far as gender was concerned. Both men and women were exposed to SARS-CoV-2 uniformly. More than 90% people, who had antibody, were asymptomatic.
“One third of people had undergone tests through Reverse transcription polymerase chain reaction (RT-PCR) or Rapid Antigen Tests which shows effectiveness of the door-to-door survey of Bhubaneswar Municipal Corporation,” she said.
‘Can’t be complacent’
“The outcome is a matter of relief because the sero-survey gives indication about what lies ahead. Since 50% are not exposed, we cannot be complacent. We need to wear mask and maintain social distancing,” the RMRC director remarked.