The risk of death, hospitalization and serious health issues from COVID-19 jumps significantly with reinfection compared with a first bout with the virus, regardless of vaccination status, a study published on Thursday suggests.

"Reinfection with COVID-19 increases the risk of both acute outcomes and long COVID," said Dr. Ziyad Al-Aly of Washington University School of Medicine in St. Louis. "This was evident in unvaccinated, vaccinated and boosted people."

The findings were drawn from U.S. Department of Veterans Affairs (VA) data collected from March 1, 2020 through April 6, 2022 on 443,588 patients with one SARS-CoV-2 infection, 40,947 with two or more infections, and 5.3 million noninfected individuals. Most of the study subjects were male.