Expansion of L452R-Positive SARS-CoV-2 Omicron Variant, Northern Lombardy, Italy

Abstract

We report 25 cases of infection with SARS-CoV-2 Omicron variant containing spike protein L452R mutation in northern Lombardy, Italy. Prevalence of this variant was >30% in this region, compared with <0.5% worldwide. Many laboratories are using previously developed L452R-specific PCRs to discriminate Omicron from Delta mutations, but these tests may be unreliable.

Keywords

• COVID-19
• SARS-CoV-2 Omicron variant
• SARS-CoV-2
• respiratory infections
• viruses
• Italy