Ghent University: Multiple organs of a Belgian COVID-19 patient infected with the UK variant before the discovery of SARS-CoV-2 VOCs
SARS-CoV-2 infection is not always confined to the respiratory system. Researchers from Ghent University and Ghent University Hospital in collaboration with the Jessa Hospital in Hasselt (Belgium) have now shown that the virus can disseminate to the blood and extrapulmonary organs in severe COVID-19 cases. Moreover, prolonged virus replication in these (extra)pulmonary sites can even be accompanied by virus evolution leading to the emergence of new variants, including variants of concern (VOCs).
They have found multiple infectious viruses with mutations hallmark to VOCs in different organs (lungs, heart, kidneys, liver, and spleen) of a severe COVID-19 patient while the patient had died long before the reported emergence of these VOCs. This study has recently been published by Nature Communications (10.1038/s41467-021-26884-7).
How is that possible?
SARS-CoV-2 dissemination out of the lungs is a rare event in COVID-19, as a healthy immune system rapidly clears the infection. However, inadequate immune responses during SARS-CoV-2 infection may fail to confine the virus to the respiratory tract. The patient in this study was under immunosuppressive therapy against B cell lymphoma cancer. Such patients cannot fight off the initial infection in the airways. This results in prolonged and enhanced SARS-CoV-2 infection with virus dissemination to other organs. SARS-CoV-2 evolves during extensive and prolonged infection throughout the body, leading to the emergence of new virus variants including variants of concern (VOCs). In VOCs, these changes have affected the virus’s properties, such as infection rate, disease severity, or the performance of vaccines.
This research shows that mutations hallmark to current VOCs were evolving in different countries at multiple sites throughout the body, including the organs of this Belgian COVID-19 patient. Indeed, a virus with mutations of concern (N501Y, T1027I, and Y453F) was not only found in the latter patient’s lungs, but also in its kidneys, heart, liver, and spleen, while the patient had died long before reported emergence of VOCs. This shows that COVID-19 treatment and hygiene measures need to be tailored to specific needs of immunocompromised patients, even when respiratory symptoms cease.
Even though infectious viruses were retrieved from this patient’s organs, we don’t know whether they could have been transmitted to other people. If this had been the case, we would not have talked about the UK variant. Instead, we would have named it the Belgian variant.