June 14, 2021

expert reaction to Lancet research letter analysing data from Scotland on the Delta variant, looking at demographics, risk of hospital admission and vaccine effectiveness

A research letter published in the Correspondence section in The Lancet analyses data on the Delta (B.1.617.2) variant, looking at demographics, risk of hospitalisation and vaccine effectiveness, and how this compares to the alpha (B.1.1.7) variant.

This Roundup accompanied an SMC Briefing.

Prof Rowland Kao, the Sir Timothy O’Shea Professor of Veterinary Epidemiology and Data Science, University of Edinburgh, said:

“This report provides important information on the impact of the recent delta variant, compared to the alpha variant previously pre-dominant in the UK with evidence that not only does it appear to be more transmissible but it also results in more hospitalisations.  The results, while generated on the basis of data from Scotland, should be relevant in terms of general outcome elsewhere in the UK and therefore are relevant to current decisions regarding the easing of COVID-19 restrictions.

“The fact that both of the two widely available vaccines appear to have some impact on both infection and hospitalisation (albeit reduced for the delta variant) is a reminder of the importance of continued vaccination as this will be one of the most important determinants in whether or not further easing in the future is likely to occur sooner rather than later.

“While hospitalisations are shown to be increased, the paper does not address the issue of demand on intensive care units, or deaths due to the delta variant, as there are as yet insufficient data on this.  These will be important determinants for any future decisions on further relaxation or, should they be merited, reintroduction of restrictions.  As infections are expected to continue to increase both due to the effects of existing levels of restriction (where R is clearly above 1) and the increased transmissibility of the delta variant, the data on deaths and ICU occupancy will continue to be monitored very closely.”

‘SARS-CoV-2 Delta VOC in Scotland: demographics, risk of hospital admission, and vaccine effectiveness’ by Aziz Sheikh et al. was published in the Lancet at 15:00 UK time on Monday 14 June 2021.

DOI: 10.1016/S0140-6736(21)01358-1

All our previous output on this subject can be seen at this weblink:

www.sciencemediacentre.org/tag/covid-19

Declared interests

Prof Rowland Kao: “SPI-M member.”