Study finds Delta variant has double the risk of hospitalisation for unvaccinated people

A new study suggests that unvaccinated people with the Delta COVID variant are twice as likely to be hospitalised compared to the Alpha strain.

Study finds Delta variant has double the risk of hospitalisation for unvaccinated people
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Study finds Delta variant has double the risk of hospitalisation for unvaccinated people

A recent report in The Lancet has revealed that the Delta variant carries a risk of hospitalisation that’s twice as high as the Alpha variant amongst unvaccinated populations.

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Delta variant hospital risk twice as high for unvaccinated patients

Researchers from Public Health England (PHE) analysed the data of 43,338 coronavirus cases in England from March 19 2021, to the 23rd of May. Of the data sampled, only 1.8% of patients were fully vaccinated, while 24% had only received one jab. The remaining three-quarters of the hoard were unvaccinated.

Co-lead author Anne Presanis, a senior statistician at the University of Cambridge’s MRC Biostatistics Unit, released in a statement:

The results from this study therefore primarily tell us about the risk of hospital admission for those who are unvaccinated or partially vaccinated.

Genome sequencing showed that around 80% of the cases were infected with the Alpha variant, while 20% were Delta. The study’s analysis also showed that 2.2% of people with Alpha and 2.3% of Delta patients were admitted to hospital with severe illness within 14 days of their first positive COVID result.

After accounting for factors that contribute to severe COVID infections like age, sex, ethnicity, and vaccine status, researchers concluded that the risk of hospitalisation was twice as high with the Delta variant for people who were unvaccinated or had their first jab less than three weeks before infection.

A similar study conducted in Scotland and published by The Lancet in June also drew the same conclusion that Delta doubled the risk of hospitalisation compared to the Alpha variant.

Presanis continued: ‘The main takeaway is that if you have an unvaccinated or only partially vaccinated population, then an outbreak of Delta can lead to a higher burden on hospitals, on health care, than an Alpha outbreak would.’

Results reinforce the importance of getting vaccinated

Since the data samples were collected, COVID’s Delta variant has become the UK’s most dominant strain and accounts for almost all cases across the nation.

Researchers agree that getting vaccinated against coronavirus is critical as multiple other studies have shown full inoculation can help prevent symptomatic infection and hospitalisation for both variants.

Already over 47.9 million people aged 16 and over have received their first dose of the COVID vaccine, while 42 million have also received their second dose.

Gavin Dabrera, a lead author and consultant epidemiologist at the National Infection Service, Public Health England, explained:

We already know that vaccination offers excellent protection against Delta, and as this variant accounts for over 98 per cent of COVID-19 cases in the U.K., it is vital that those who have not received two doses of vaccine do so as soon as possible.
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