The Delta variant of the Sars-CoV-2 coronavirus – which has now become predominant – it is not only more transmissible, but is also associated with greater Covid-19 severity. However, the anti-Covid vaccination is confirmed as protective against serious forms of the disease. This is what emerges from a retrospective study published in ‘Clinical Infectious Diseases’, the results of which suggest the need for “rapid implementation of vaccination programs”, reads the conclusions of the work, conducted in Singapore by comparing the clinical and virological characteristics of the Alpha, Beta and Delta variants.
The study examined the cases of 829 patients infected with one of the three variants of concern (VOC) from 20 December 2020 to 12 May, comparing them with those of 846 Covid patients hospitalized between January and April 2020. The results, corrected taking into account possible confounding factors indicate that the Delta variant was associated with an increased risk of pneumonia, oxygen requirement, ICU admission or death. Vaccination status appeared to be related to reduced disease severity.