Approximately 27.3 percent of Karnataka’s population may have been exposed to the the novel coronavirus, said a serosurvey conducted by the state government.
About 16.4 percent of the 15,624 samples studied during the survey had developed antibodies against COVID-19 as of 16 September, the report added.
“Out of the 7.07 crore estimated population in Karnataka, the study estimates that 1.93 crores (27.3 percent) of the people are either currently infected or already had the infection in the past, as of 16 September 2020,” the report said.
Karnataka’s health minister K Sudhakar said that the survey provides an indication of the regions which have already witnessed a surge and those that are likely to see a rise in infections.
North Karnataka’s Ballari has the highest prevalence of 43.1 percent, followed by Davangere (40.6 percent), Udupi (36.4 percent), Vijayapura (35.4 percent) and Raichur (34.1 percent). The lowest prevalence was reported in Dharwad (of 8.7 percent).
Bengaluru urban reported a prevalence rate of 29.8 percent.
The survey was done from 3 September to 16 September and it includes the proportion of people who had COVID-19 infection recently and those currently having active infection. The survey was carried out on 15,624 persons in 290 hospitals on persons above the age of 18 across all 30 districts of the state.
Experts, however, said that the numbers provided in the report could be an overestimation since the survey was carried out in hospitals and there were limited population samples.
The survey also found that 40 undetected infected individuals were noted for every RT-PCR confirmed case, indicating the case-to-undetected-infections ratio (CIR) to be at 1:40.
Sudhakar said that the sero survey will be conducted in December and March again.