Sero-surveys use tests that examine the liquid part of blood, or “serum”, not the nose, throat and mouth fluid.Antibodies against the Covid-19 infection have been found in 27.7 per cent of people in Punjab’s containment zones, indicating that they have already been infected by and recovered from the novel coronavirus, according to the findings of a sero-survey report.
The survey findings, submitted to Chief Minister Capt Amarinder Singh during a Covid review meeting Thursday, showed the SARS-CoV2 antibodies prevalence in the containment zones to be the highest at 40 per cent in Amritsar district, followed by 35.6 per cent in Ludhiana, 33.2 per cent in SAS Nagar, 19.2 per cent in Patiala district and 10.8 per cent in Jalandhar.
This was Punjab’s first exclusive survey, and was conducted in five containment zones from August 1 to 17, in systematically selected random sample population of 1,250. The earlier surveys were more generalised and were conducted by the state in coordination with ICMR, said a government statement.
The survey report came on the day when Delhi released its second sero survey findings, which showed nearly 29 per cent seroprevalence in the national capital.
For the Punjab survey, the selected containment zones, which had reported the highest number of Covid cases, were located one each in Patiala, SAS Nagar, Ludhiana, Jalandhar, and Amritsar districts. The sample included 250 people from each zone. From each of the selected households, one adult above the age of 18 was randomly chosen for the survey.
Overall, the seroprevalence of SARS CoV-2 antibodies was found to be 27.7 per cent in the containment zones where the highest number of Covid-19 cases had been reported. However, in the remaining parts of the cities, the SARS CoV-2 prevalence would be lower, as per the survey report. In the rural areas the prevalence would be much lower than the urban areas, as per the survey, which sought to find out the SARS-CoV-2 antibodies (IgM/IgG) using rapid antibody testing kits.
Health advisory expert group head Dr KK Talwar said a team of trained field assistants and laboratory technicians collected the data under the supervision of a medical officer.
Accredited Social Health Activists and Auxiliary Nurse Midwifes facilitated the survey by identifying the households in the zones.
After explaining the purpose of the survey, written informed consent was obtained, following which a laboratory technician collected a venous blood sample under aseptic conditions. The blood samples were taken to the district public health laboratory where rapid antibody tests were performed.