The UK variant is likely deadlier, more infectious and becoming dominant. But the vaccines still work well against it
New research published this week in the British Medical Journal found the coronavirus variant originating in the United Kingdom, called B.1.1.7, is substantially more deadly than the original strain of SARS-CoV-2.
The authors say the B.1.1.7 variant is between 32 and 104% deadlier. However, it’s important to recognise these data were only collected from one group of people so more research is needed to see if these numbers hold true in other groups of patients.
The B.1.1.7 variant is becoming the dominant virus in many parts of the world, and is more infectious than the original strain (UK authorities have suggested it’s up to 70% more transmissible). This makes sense because a virus can become more transmissible as it evolves. However, it’s actually a strange thing for a virus to become more deadly over time (more on that later).
What did the study find?
There are two ways to check if someone has this variant. The first is by doing full genomic sequencing, which takes time and resources. The other, easier way, is to analyse results from the standard PCR test, which normally takes a swab from your nose and throat.
This test targets two viral genes in the swab sample, one of which doesn’t work very well with this variant (it’s called the “S-gene”). So if someone was positive for one of these genes, but negative for the “S-gene”, there’s a good chance they’re infected with the B.1.1.7 variant.
The study authors looked at the S-gene status of 109,812 people with COVID, and looked at how many died. They found S-gene negative people had a higher chance of dying 28 days after testing positive for the virus. The study “matched” patients in the S-gene positive and S-gene negative groups based on various factors (including age) to ensure these factors didn’t confound the results.