Researchers in Belgium report on the case of a 90-year-old woman who was simultaneously infected with two different COVID variants.
On March 3 2021, the woman, with an unremarkable medical history, was admitted to a Belgian hospital after a spate of falls. She tested positive for COVID on the same day. She received nursing care at home, where she lived alone, and had not received a COVID vaccination.
At first, no signs of respiratory distress were seen, and oxygen saturation was good. However, she went on to develop rapidly worsening respiratory symptoms, and died five days later.
PCR testing revealed that she had been infected by two different strains of the virus — one which originated in the UK, known as B.1.1.7 (Alpha), and another that was first detected in South Africa (B.1.351; Beta).
“This is one of the first documented cases of co-infection with two SARS-CoV-2 variants of concern”, says lead author and molecular biologist Dr. Anne Vankeerberghen from the OLV Hospital in Aalst, Belgium. “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.”
The Alpha variant had been detected in the south east of England in December and within weeks, this variant displaced the viral strains circulating there. Since then, it has spread to more than 50 countries, including Belgium. The Beta variant was reported on December 18, 2020, and has since spread to 40 countries, which also includes Belgium.
Scientists in Brazil reported in January 2021 that two people had been simultaneously infected with two different strains of the coronavirus—the Brazilian variant known as B.1.1.28 (E484K) and a novel variant VUI-NP13L, which had previously been discovered in Rio Grande do Sul. However, this study has yet to be published in a scientific journal.
“Whether the co-infection of the two variants of concern played a role in the fast deterioration of the patient is difficult to say”, said Vankeerberghen. “Up to now, there have been no other published cases. However, the global occurrence of this phenomenon is probably underestimated due to limited testing for variants of concern and the lack of a simple way to identify co-infections with whole genome sequencing.”
She continued, “Since co-infections with variants of concern can only be detected by VOC-analysis of positive samples, we would encourage scientists to perform fast, easy and cheap VOC-analysis by PCR on a large proportion of their positive samples, rather than just whole genome sequencing on a small proportion. Independent of the technique used, being alert to co-infections remains crucial.”