The Covid Pirola variant was isolated in Italy, in Brescia, while Eris is confirmed as predominant in Italy. But are the symptoms always the same? “Continuous monitoring of new mutations” of Sars-CoV-2 “remains crucial. Currently, despite the identification of 102 specific point mutations, there is no substantial evidence to classify BA.2.86 or ‘Pirola’ and its descendants as highly worrisome. Indeed, the prolonged presence of BA.2.86 contrasts with the usual trend of potentially dangerous variants, which are typically identified quickly. The development of new mutations in emerging variants is a standard event, driven by genetic drift, facilitating the adaptation of the virus to its host”. Thus the conclusions of an Italian study to be published, which analyzed the new variant BA.2.86.
“However, this genetic drift did not invariably lead to increased virulence or fitness. A key lesson from the pandemic highlights the importance of sustained, genome-based surveillance in anticipating the potential for epidemic waves,” the researchers point out. Francesca Caccuri and Serena Messali of the University of Brescia, Fabio Scarpa of the University of Sassari, Massimo Ciccozzi of the Campus Bio-Medico University of Rome, Arnaldo Caruso of the University of Brescia and Marta Giovannetti, Instituto Rene Rachou of the Fundação Oswaldo Cruz, Minas Gerais (Brazil).
“The E484K mutation, found in BA.2.86 and BA.2.86.1 – explain the authors – is located within the receptor binding (Rbd) and has previously attracted attention due to its association with various significant concerns. In particular – the researchers point out – the E484K mutation has been detected in multiple viruses, 94 variants, such as the B.1.351 strain from South Africa and the P.1 strain from Brazil. The variants carrying this mutation appear to show a greater ability to escape immune system responses, which include antibodies generated by previous infections or vaccinations. This implies that viruses with the E484K mutation may possess an intrinsically greater potential for evolution. Reinfections involving variants with the E484K mutation are documented and therefore – the authors point out – investigations into the lasting protection conferred by the immune system must be further intensified”.