British variants of SARS-CoV-2 can be more deadly than previous strains

Researchers found that the B.1.1.7 variant of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which emerged in the United Kingdom, is at risk of death compared to previously prevalent virus strains. We conducted a study showing that it was associated with a significant increase. domestic.

The SARS-CoV-2 virus is the causative agent of the coronavirus disease 2019 (COVID-19) pandemic, currently causing more than 117 million infectious diseases and killing more than 2.6 million people worldwide. I have.

A team study of the unvaccinated population found that the B.1.1.7 variant (VoC) of concern was associated with two-thirds higher. Case fatality rate, Compared to previously circulating strains in this population. The risk of death was higher in men than in women and increased with age and the number of comorbidities.

The B.1.1.7 mutant has become the predominant SARS-CoV-2 strain in the United Kingdom and is now widespread throughout Europe.

Daniel Grint and colleagues at the London School of Hygiene & Tropical Medicine warn that policy makers need to consider the high mortality rates associated with this VoC.

They also state that the study emphasizes the importance of strong national vaccination programs and infection control measures to control the spread of SARS-CoV-2.

The team warns that the uncontrolled spread of the B.1.1.7 variant can be faster and more deadly than ever seen during a pandemic.

The preprinted version of the research treatise is medRxiv* The server while the article is being peer reviewed.

B.1.1.7 Variants that may dominate across Europe

The B.1.1.7 mutant, first identified in the United Kingdom in the fall of 2020, could now be the most common SARS-CoV-2 strain throughout Europe.

Early studies suggested that this VoC was more infectious than previously circulating strains and was associated with increased mortality.

However, previous reports of increased mortality did not include data on individual comorbidities, Grint and the team said.

“Accurate estimates of the severity of this VoC-related disease are important for pandemic planning,” they write.

What did the researchers do?

On behalf of NHS England, the team extracted data from the OpenSAFELY Electronic Health Record (EHR) secure research platform, which covers 40% of the UK’s population enrolled in the General Practitioner (GP).

Post-diagnosis of non-VoC strains between SARS-CoV-2 infection with B.1.1.7 variant and 16 using linked GP, SARS-CoV-2 test, vaccination, and mortality data Estimated lethal risk.^th November 2020 and 11^th January 2021.

Infected cases were followed up to 5^th February 2021 or 7 days prior to SARS-CoV-2 vaccination, whichever comes first.

Demographically adjusted models include adjustments for age, gender, IMD, ethnicity, household size, rural city classification, epidemiological weeks, and care facility status. Fully tuned models include adjustments for age, gender, IMD, ethnicity, smoking status, obesity, household size, local urban classification, comorbidities, epidemiological weeks, and care facility status. There was no evidence of non-proportional hazards in this model (Global test of Schoenfeld residuals, P = 0.19).

What did the study find?

Cox regression analysis revealed that after fully adjusting demographics and comorbidities, infection with the B.1.1.7 variant increased the risk of death by 67% compared to non-VoC infection.

An analysis of the absolute risk of death within 28 days of a SARS-CoV-2 positive test showed that VoC infections were associated with a 73% increased chance of death compared to non-VoC infections. It was.

The 28-day risk of death was lower in people under the age of 65 without comorbidities, but higher in men than in women.

The risk of death for men and women in this group by day 28 was 0.14% and 0.07% for VoC infections, respectively, while they were 0.09% and 0.05% for non-VoC infections, respectively.

The risk of death was consistently higher in men and increased with age and the number of comorbidities.

Patients aged 85 years and older with two or more comorbidities were at greatest risk. The risk of death for men and women in this group was 24.3% and 14.7% for VoC infections, respectively, but 16.7% and 9.7% for non-VoC infections, respectively.

B.1.1.7 VoC can spread faster and be more deadly

“This VoC was found to be associated with two-thirds higher mortality rates than previously prevalent viruses in unvaccinated populations,” Grint et al. Wrote.

“This unmitigated spread of VOCs can be faster and more deadly than we’ve seen in previous pandemics,” they warn.

Researchers conclude that the new data suggest that the currently approved vaccine for SARS-CoV-2 is effective against the B.1.1.7 mutant. ..

“This study emphasizes the importance of a strong national vaccination program and infection control measures to contain the SARS-CoV-2 pandemic,” the team concludes.

*Important Notices

medRxiv Publish preliminary scientific reports that should not be considered definitive as they are not peer-reviewed, guide clinical practice / health-related behaviors, and should not be treated as established information.