The risk of death, hospitalisation and serious health issues from COVID-19 jumps significantly with reinfection compared with a first bout with the virus, regardless of vaccination status, according to a study published on Thursday (Nov 10).
“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 US Department of Veterans Affairs data collected from Mar 1, 2020 through Apr 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.
Reinfected patients had a more than doubled risk of death and a more than tripled risk of hospitalisation compared with those who were infected with COVID-19 just once. They also had elevated risks for problems with lungs, heart, blood, kidneys, diabetes, mental health, bones and muscles, and neurological disorders, according to a report published in Nature Medicine.
“Even if one had prior infection and was vaccinated – meaning they had double immunity from prior infection plus vaccines – they are still susceptible to adverse outcomes upon reinfection,” Al-Aly, the study leader, said.