A 90-year-old Belgian has died after suffering simultaneous infections from two COVID-19 variants. 

Bloomberg reports the unvaccinated woman tested positive after admission to the OLV hospital in Aalst in March after she fell multiple times. Her oxygen levels were initially good, but her condition rapidly deteriorated and she died five days later.

An autopsy has now revealed that she was infected with both the Alpha and Beta variants at the time of her death. 

“This is one of the first documented cases of co-infection with two SARS-CoV-2 variants of concern,” Anne Vankeerberghen, who led the research, told the Times of Israel. “Both these variants were circulating in Belgium at the time, so it is likely that the lady was co-infected with different viruses from two different people.” 

“Unfortunately we don’t know how she became infected,” she added. 

Vankeerberghen said it was difficult to say whether the co-infection played a role in the fast deterioration of the patient. While she stated there had been “no other published cases” of similar co-infections, she added that the “phenomenon is probably underestimated”.

In January, scientists in Brazil reported that two people had been simultaneously infected with two different strains of the coronavirus, but the study has yet to be published in a scientific journal.

In comments reacting to the research, Lawrence Young, a virologist and Professor of Molecular Oncology at the University of Warwick, said it was not a surprise to find an individual infected with more than one strain.

“This study does highlight the need for more studies to determine whether infection with multiple variants of concern affects the clinical course of Covid-19 and whether this in any way compromises the efficacy of vaccination,” he added.