Chandigarh, Jun 21 (IANS): Delta (B.1.617.2) and Alpha variants (B.1.1.7) were found to be present in the second wave of coronavirus among 61 and 30 per cent, respectively, of the samples sent for whole genome sequencing, PGI Hospital Director Jagat Ram said on Monday.

The majority of these samples (92 per cent) belonged to residents of Chandigarh. Thus, during the second wave in Chandigarh, Delta strain was the main circulating strain, he said.

"The Department of Virology of the PGIMER has been carrying out the Covid-19 testing by RT-PCR since March 2020 and till date more than 2.5 lakh samples have been tested. To study whether there was any change in the circulating strain in Chandigarh during the second wave, 25 stored positive samples of the period May 5 to May 24 were sent for whole genome sequencing to the NCDC in New Delhi."

PGI's Dean, Academics, G.D. Puri, said the samples sent from admitted patients in Nehru Hospital Extension Block, where severe and critical Covid positive cases are admitted, belonged to Delta strain.

As many as 80 per cent of the patients who had died of Covid-19 harbored the Alpha strain. Fortunately, no case of Delta plus variant was reported in the samples sent, he added.

Against this backdrop, the PGI Director advised the public to adhere to Covid appropriate behaviour and also to opt for vaccination in increased numbers so as to break the transmission chain completely and to halt the impending threat of third wave keeping in view the emerging and fast spreading Delta and Delta plus variant.