A British study suggests that people receiving COVID-19 from the Delta variant are about twice as likely to be hospitalized compared to the Alpha variant.
The Delta variant of the coronavirus that causes COVID-19 doubles the risk of hospitalization compared to the Alpha variant that has supplanted it as a dominant strain worldwide, The Lancet reported Saturday.
Only 1.8 percent of the more than 43,000 cases of COVID-19 evaluated in the comparison of the two variants were in patients who had been fully vaccinated.
Three-quarters were not fully vaccinated and 24% had only received an injection of a two-dose vaccine.
“The results of this study, therefore, tell us primarily about the risk of hospital admission for those who are not vaccinated or partially vaccinated,” said Anne Presanis, lead co-author, statistician of the University’s MRC Biostatistics Unit of Cambridge.
The researchers analyzed health data from 43,338 cases of COVID-19 in England from March 29 to May 23 this year, including vaccination status, emergency care, hospital admission and more. patient information.
All virus samples underwent complete genome sequencing, the surest way to confirm which variant had caused the infection.
Just under 80% of cases were identified as Alpha variant and the rest were Delta.
Approximately one in 50 patients was admitted to hospital 14 days after the first positive test for COVID-19.
After considering the factors that are known to affect susceptibility to serious diseases (including age, ethnicity, and vaccination status), the researchers found that the risk of hospitalization was higher. of the double with the Delta variant.
“Excellent protection”
Since these samples were taken, Delta has grown and now accounts for more than 98 per cent of new cases of COVID-19 in Britain, the authors said.
Several studies have shown that full vaccination prevents symptomatic infection and hospitalization of both Alpha and Delta variants.
“We already know that vaccination offers excellent protection against Delta,” said Gavin Dabrera, another lead author and consultant epidemiologist for the National Infection Service, Public Health England.
“It is vital that those who have not received two doses of vaccine do so as soon as possible.”
A previous Scottish study also reported a doubling of the risk of hospitalization with Delta over Alpha, suggesting that Delta causes more serious illnesses.
The Delta variant was first reported in India in December 2020 and early studies found that it was up to 50 per cent more transmissible than the Alpha variant, which was first identified in England in September last year.
Nearly 4.5 million deaths worldwide have been attributed to COVID-19, although the final tally is likely to be higher once the “excess deaths” are calculated during the pandemic period.
In some countries – and in some states in the United States – hospitalization and mortality rates are the highest since the first cases reported in early 2020.