A case report presented at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) analyzes a 90-year-old woman infected with two worrisome variants of SARS-CoV-2; alpha and beta.
It happened like that
On March 3, 2021, the woman, whose medical history was uncomplicated, was admitted to hospital in Aalst (Belgium) after a series of falls. He tested positive for COVID-19 the same day. She lived alone and received nursing care at home, and had not been vaccinated against COVID-19.
Initially, there were no signs of respiratory distress and the patient had a good oxygen saturation. However, he developed respiratory symptoms that quickly worsened and died five days later.
When the respiratory sample of the patient was analyzed by performing the PCR, they discovered that it had been infected by two different strains of the virus, one that originated in the United Kingdom, known as B.1.1.7 (Alpha), and another that was detected for the first time in South Africa (B.1.351; Beta).
The presence of both strains was confirmed by PCR in a second respiratory sample, by S gene sequencing and whole genome sequencing.
“This is one of the first documented cases of coinfection with two worrisome variants of SARS-CoV-2,” says lead author and molecular biologist Dr. Anne Vankeerberghen of OLV Hospital in Aalst, Belgium. “Both variants were circulating in Belgium at the time, so it is likely that the woman was co-infected with different viruses from two different people. Unfortunately, we do not know how she became infected.”
Implications of this case study
Is it an extraordinary case, or could the simultaneous presence of both variables be responsible for the worsening of the symptoms? “This is not the first time that an infection with more than one variant of SARS-CoV-2 has been detected in the same individual. The reality is that the variants of the virus are continuously being produced in any infected person, and these multiple variants are transmitted to other people who then produce other variants ”, explains to Science Media Center Lawrence Young, virologist at the University of Warwick (United Kingdom ).
“The variants that dominate the infection are those with the highest fitness, which is defined as the ability to more efficiently infect the cells of our nose and throat, as well as the ability to bypass our immune system. Detection of infection with different variants depends on the replication levels of individual variants and the sensitivity of our sequencing technology to detect these variants. The detection of two dominant worry variants in a single person is not surprising ; these could have been transmitted by a single infected person or by contact with several infected people. There is no evidence that this two-variant infection was in any way responsible for the clinical outcome in this case. This study does highlight, yes, the need for more studies to determine if the infection with multiple variants affects the clinical course of COVID-19 and if this in any way compromises the efficacy of vaccination ”.
