COVID-19 vaccines highly effective against hospitalisation by Delta variant

New data from Public Health England (PHE) demonstrates that Pfizer/BioNTech’s Comirnaty® and the COVID-19 Vaccine AstraZeneca are both effective at preventing hospitalisation from the Delta SARS-CoV-2 variant.

SARS-CoV-2 is the virus that causes COVID-19. Since its emergence in 2019, several genetic variants have emerged. The Delta variant (formerly the B.1.617.2 variant) was first identified in India in October 2020 and designated a variant of concern by the World Health Organization for its increased transmissibility. PHE previously established that the Delta variant is up to 64 percent more transmissible than the Alpha variant (formerly the B.1.1.7- variant), first identified in the UK in September 2020.

According to the new PHE analysis, after two doses:

• Pfizer/BioNTech’s Comirnaty® is 96 percent effective at preventing hospitalisation from the Delta SARS-CoV-2 variant;

• and the COVID-19 Vaccine AstraZeneca is 92 percent effective against hospitalisation.

These are comparable with vaccine effectiveness against hospitalisation from the Alpha variant.

The analysis included 14,019 cases of the Delta variant – 166 of whom were hospitalised – between 12 April and 4 June, looking at emergency hospital admissions in England.

While research is ongoing to establish the level of protection against mortality from the Delta variant, as with other variants, this is expected to be high. Another recently published PHE analysis showed that one dose is 17 percent less effective at preventing symptomatic illness from the Delta variant, compared to Alpha, with only a small difference after 2 doses.

Dr Mary Ramsay, Head of Immunisation at PHE, commented: “These hugely important findings confirm that the vaccines offer significant protection against hospitalisation from the Delta variant.

“The vaccines are the most important tool we have against COVID-19. Thousands of lives have already been saved because of them. It is absolutely vital to get both doses as soon as they are offered to you, to gain maximum protection against all existing and emerging variants.”

Vaccines Minister, Nadhim Zahawi added: “It is extremely encouraging to see today’s research showing that vaccines are continuing to help break the link between hospitalisation and the Delta variant after one dose, and particularly the high effectiveness of 2 doses.

“If you are getting the call to bring forward your second dose appointment – do not delay – get the second jab so you can benefit from the fullest possible protection.”

A separate PHE analysis indicates that the COVID-19 vaccination programme has so far prevented 14,000 deaths and around 42,000 hospitalisations in older people in England, up to 30 May.