Aug. 27 (UPI) — People infected with the Delta variant of COVID-19 have approximately double the risk for hospitalization compared to those infected with other varieties of the virus, according to a study published Friday.
In addition, the risk for visiting the hospital emergency room due to symptoms of COVID-19 or being admitted to the hospital within 14 days of infection is 1.5 times higher with the Delta variant than the earlier version of the virus, researchers reported in the study published in Lancet Infectious Diseases.
“This study confirms previous findings that people infected with Delta are significantly more likely to require hospitalization than those with Alpha, although most cases included in the analysis were unvaccinated,” study co-author Gavin Dabrera said in a press release.
“We already know that vaccination offers excellent protection against Delta and it is vital that those who have not received two doses of vaccine do so as soon as possible,” said Dabrera, a consultant epidemiologist at the National Infection Service for Public Health England in London, where the research was conducted.
The Delta variant first was identified in India in the later winter, while the Alpha variant, or “U.K. variant,” first was reported in England in September, according to Dabrera and his colleagues.
Their findings are based on an analysis of healthcare data from more than 43,000 positive COVID-19 cases in England between March 29 and May 23, including information on vaccination status, emergency care attendance, hospital admission and other demographic characteristics.
In all cases included in the study, samples of the virus taken from patients underwent whole genome sequencing to confirm which variant had caused the infection, the researchers said.
During the study period, nearly 35,000 cases of the alpha variant and nearly 8,700 cases of the Delta variant occurred, they said.
Although the proportion of Delta cases in the study period was 20%, the strain grew to account for around two-thirds of new COVID-19 cases in the week starting May 17, an indication that it had overtaken alpha to become the dominant variant in England, according to the researchers.
However, fewer than 2% of the cases involving either variant had received both doses of a COVID-19 vaccine, while 74% were unvaccinated and 24% were partially vaccinated, they said.
“Our analysis highlights that in the absence of vaccination, any Delta outbreaks will impose a greater burden on healthcare than an Alpha epidemic,” study co-author Anne Presanis said in a press release.
“Getting fully vaccinated is crucial for reducing an individual’s risk of symptomatic infection with Delta in the first place, and, importantly, of reducing a Delta patient’s risk of severe illness and hospital admission,” said Presanis, senior statistician at the University of Cambridge in England.
The U.S. Food and Drug Administration last week gave full approval for the Pfizer-BioNTech shot to be used in people 16 and older. People ages 12 to 15 are eligible to receive the vaccine under the FDA’s emergency use authorization.
Nearly 165,000 new COVID-19 cases were reported across the United States on Thursday, with at least 80% of them the more contagious Delta variant, based on CDC data.