Aug 28, 2021 - Health

Study: People infected with Delta variant twice as likely to be hospitalized

Picture of a health worker taking care of a hospital COVID-19 patient
A health care worker treats a patient for complications resulting from COVID-19 inside the intensive care unit at Freeman Hospital West in Joplin, Missouri this month. Photo: Angus Mordant/Bloomberg via Getty Images

Those infected with the Delta variant are twice as likely to be hospitalized as people with the Alpha strain, according to a study published in The Lancet on Friday.

By the numbers: The study evaluated more than 43,300 coronavirus cases that took place from March 29 to May 23, with approximately 74% of individuals who were unvaccinated.

  • Research in India has determined that Delta is 50% more contagious.
  • Of those patients, 8,682 were infected with the Delta variant and 34,656 were infected with the original strain. Of the patients with the Delta variant, 2.3% were hospitalized, compared to 2.2% of those with the original strain within 14 days of testing positive.
  • 5.7% of those with Delta vs. 4.2% of those with the Alpha variant were admitted to hospitals or attended emergency care.
  • Overall, "[t]his large national study found a higher hospital admission or emergency care attendance risk for patients with COVID-19 infected with the delta variant compared with the Alpha variant."

What they're saying: "Results suggest that outbreaks of the delta variant in unvaccinated populations might lead to a greater burden on health care services than the Alpha variant," the study says.

  • "Getting fully vaccinated is crucial for reducing an individual’s risk of symptomatic infection with Delta," Anne Presanis, one of the study’s lead authors and a senior statistician at Cambridge, told Bloomberg.

The big picture: These findings agree with those from the Centers for Disease Control and Prevention, which in late July determined that infection and hospitalization rates were 5 and 29 times higher, respectively, among unvaccinated people in Los Angeles County than the fully vaccinated.

Zoom out: 52% of the entire population is fully vaccinated, according to CDC data.

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