Of 69 Apollo workers who tested Covid-positive after vaccine, 48% infected by B1.617.2 variant

The B1.617.2 variant was first identified in India and has been declared a Variant of Concern by the WHO. No casualty reported among those studied.

A nurse exits a door to operating rooms at an Apollo Speciality Hospital | Dhiraj Singh | Bloomberg

New Delhi: In a genome sequencing study on 69 healthcare workers (HCWs) at the Apollo Hospital in the national capital who tested positive for Covid-19 after vaccination, nearly 48 per cent were found to have been infected with the B1.617.2 variant.

The variant was first identified in India and has been declared a Variant of Concern (VoC) by the World Health Organization.

All 69 HCWs had been vaccinated with Covishield prior to the infection. While 51 had received double doses, 18 had received one dose. No casualty was reported among this group.

“The predominant infections occurred from B.1.617.2 lineage (47.83%), followed by B.1 and B.1.1.7 strains. There were only two hospital admissions (2.89%) for minor symptoms, but no ICU admissions and deaths, from this group,” Dr Anupam Sibal, Group Medical Director and Senior Pediatric Gastroenterologist, Apollo Hospitals, said in a statement.

“These findings are significant because more than half of the cohort were found infected with the Variant of Concern (VoC) and still escaped from the severe illness, which could have been a severe event for them without vaccination coverage,” he added, referring to the three strains mentioned earlier.

Study aims to encourage vaccinations

The study in its conclusion encouraged people towards vaccination as it helps with overcoming the infection of the VoC with no hospitalisation and minor symptoms.

This study is in continuation of Apollo’s study on cases of breakthrough infections among 3,235 vaccinated healthcare workers employed at the hospital. The previous study had found that only 2.62 per cent of its fully vaccinated staff had been infected within 100 days of receiving the vaccine.

Infections occurring two weeks after full vaccination are referred to as ‘breakthrough infections’.

The Apollo study analysed nasopharyngeal samples for genome sequencing, in collaboration with the National Centre for Disease Control (NCDC). Genome sequencing is the key test to identify the nature of the virus and the variants that may emerge.

‘Covishield is effective in reducing effect of VoC’

According to Dr Raju Vaishya, senior consulting orthopaedic and the key author, the study was conducted between 16 January and 24 April — the 100-day period when the HCWs were first vaccinated in the country.

“Of these 3,235 staff members, 85 were found to have the Covid infection. Samples of 69 of these were sent to the NCDC lab to be further studied. Only two of these staff members required hospitalisation, this shows that the Covishield vaccine is effective in reducing the effect of the virus of concern,” he told ThePrint.

“Another trend that we observed was that even after the first dose, the HCWs had adequate protection. My advice would be to not lower your guard if you are not fully immunised. The chances of infection are high. Even after immunisation it is important to be careful because one can become a carrier of the virus,” he added.