It's been five years since the worst health crisis of the 21st century. COVID-19 turned the world upside down, with millions of infected people and deaths overwhelming healthcare systems and nearly collapsing in many countries. The arrival of vaccines, on the one hand, and the constant mutations of the virus, on the other, have allowed it to become another disease in the season of respiratory viruses, such as the flu. This is due to a new mutation called NB.1.8.1, which has already been placed under surveillance. However, for the moment, the risk is low, both in mild and severe symptomatic cases. As of mid-May, 518 positive samples of NB.1.8.1 have been identified from 22 countries, that is, one in ten samples sequenced worldwide. "significant" compared to recent weeks. In Catalonia, the predominant variant It is still the JN.1, although cases have been increasing in recent weeks, going from fewer than 300 at the end of April to more than 700 in mid-May, according to data from the Information System for Infection Surveillance in Catalonia.

The expansion across Catalonia of the variant of covid-19 identified in the United Kingdom is unstoppable. There are already regions such as the Garrotxa where the mutation represents a large part of the infections. The Department of Health has detailed this Wednesday that, until February 2, approximately 30% of the samples of wastewater analysed in the treatment plant of Olot corresponded to this variant. "This indicates the trend where the mutation is taking hold, which probably displaces the original because it is faster and more transmissible," explained Albert Bosch, professor of microbiology at the University of Barcelona and leader of a research team on enteric viruses.