Coronavirus: Volunteers at Serum’s Covid vaccine trials test positive

Vaccine maker Serum Institute of India’s phase III trials of Covishield are facing minor hiccups. Trials of the Oxford University-AstraZeneca vaccine resumed on Tuesday in Pune’s Sassoon General Hospital. Seven volunteers were recruited for this. Three of the volunteers tested positive for antibodies after both antigen and RT-PCR tests were conducted. This indicated that they had already got infected by the Covid-19 virus and would not be able to participate in the trials. These volunteers cannot be vaccinated and the hospital will now have to recruit fresh set of volunteers.

This was a repeat of what happened in the trial at another hospital in Pune last month. Bharati Hospital and Research Centre, one of the sites for the Serum Covid vaccine trial, too, witnessed volunteers turning positive prior to the vaccination. At Bharati, three of the five volunteers tested positive for antibodies just before they could be vaccinated. These volunteers did not have any symptoms of the infection and were not aware that they had the virus, health officials said. The volunteers, who are above 18 years of age and without any comorbidity, will have to test negative on both RT-PCR as well as antigen tests to be fit for vaccination.

This development confirms Pune’s sero survey that was carried out in May 2020, which put Covid-19 infection rate at 51%. Since then, the infection has spread across the district with 2.67 lakh cases. There are 59,774 active cases and 5,368 deaths till date.

Serum Institute’s spokesperson said the company would not be commenting on trials while the process was going on and would speak only after the results were out.

Serum has partnered with AstraZeneca to carry out trials and has to cover 1,600 participants across 17 trial sites in India.